Merge 9ce5c8afee into 8f3291d316

* fix: decode properties array bracket paths

* test: add nested array bracket properties decode case

---------

Co-authored-by: cyphercodes <cyphercodes@users.noreply.github.com>

.github/workflows/codeql.yml

@@ -20,6 +20,8 @@ on:
   schedule:
     - cron: '24 3 * * 1'
 
+permissions: {}
+
 jobs:
   analyze:
     name: Analyze
@@ -38,11 +40,11 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v6
+      uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v4
+      uses: github/codeql-action/init@95e58e9a2cdfd71adc6e0353d5c52f41a045d225 # v4.35.2
       with:
         languages: ${{ matrix.language }}
         # If you wish to specify custom queries, you can do so here or in a config file.
@@ -53,7 +55,7 @@ jobs:
     # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
     # If this step fails, then you should remove it and run the build manually (see below)
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v4
+      uses: github/codeql-action/autobuild@95e58e9a2cdfd71adc6e0353d5c52f41a045d225 # v4.35.2
 
     # ℹ️ Command-line programs to run using the OS shell.
     # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
@@ -67,4 +69,4 @@ jobs:
     #   make release
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v4
+      uses: github/codeql-action/analyze@95e58e9a2cdfd71adc6e0353d5c52f41a045d225 # v4.35.2

.github/workflows/docker-release.yml

@@ -7,23 +7,28 @@ on:
   # Allows you to run this workflow manually from the Actions tab
   workflow_dispatch:
 
+permissions: {}
+
 jobs:
   publishDocker:
     environment: dockerhub
     env:
       IMAGE_NAME: mikefarah/yq
     runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
       - name: Set up QEMU
-        uses: docker/setup-qemu-action@v4
+        uses: docker/setup-qemu-action@ce360397dd3f832beb865e1373c09c0e9f86d70a # v4.0.0
         with:
           platforms: all
 
       - name: Set up Docker Buildx
         id: buildx
-        uses: docker/setup-buildx-action@v4
+        uses: docker/setup-buildx-action@4d04d5d9486b7bd6fa91e7baf45bbb4f8b9deedd # v4.0.0
         with:
           version: latest
 
@@ -31,13 +36,13 @@ jobs:
         run: echo ${{ steps.buildx.outputs.platforms }} && docker version
 
       - name: Login to Docker Hub
-        uses: docker/login-action@v4
+        uses: docker/login-action@4907a6ddec9925e35a0a9e82d7399ccc52663121 # v4.1.0
         with:
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}
 
       - name: Login to GitHub Container Registry
-        uses: docker/login-action@v4
+        uses: docker/login-action@4907a6ddec9925e35a0a9e82d7399ccc52663121 # v4.1.0
         with:
           registry: ghcr.io
           username: ${{ github.actor }}

.github/workflows/go.yml

@@ -11,13 +11,13 @@ jobs:
     steps:
 
     - name: Set up Go
-      uses: actions/setup-go@v6
+      uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c # v6.4.0
       with:
         go-version: '^1.20'
       id: go
 
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v6
+      uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
     - name: Get dependencies
       run: |

.github/workflows/release.yml

@@ -5,12 +5,17 @@ on:
       - 'v4.*'
       - 'draft-*'
 
+permissions: {}
+
 jobs:
   publishGitRelease:
     runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      id-token: write
     steps:
-      - uses: actions/checkout@v6
-      - uses: actions/setup-go@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c # v6.4.0
         with:
           go-version: '^1.20'
           check-latest: true
@@ -37,14 +42,22 @@ jobs:
             --output=yq.1
             man.md
 
+      - name: Install cosign
+        uses: sigstore/cosign-installer@v3
+
       - name: Cross compile
         run: |
           sudo apt-get install rhash -y
           go install github.com/goreleaser/goreleaser/v2@latest
           ./scripts/xcompile.sh
 
+      - name: Sign checksums
+        run: |
+          cosign sign-blob --yes --bundle build/checksums.bundle build/checksums
+          cosign sign-blob --yes --bundle build/checksums-bsd.bundle build/checksums-bsd
+
       - name: Release
-        uses: softprops/action-gh-release@v1
+        uses: softprops/action-gh-release@b4309332981a82ec1c5618f44dd2e27cc8bfbfda # v3.0.0
         with:
           files: build/*
           draft: true

.github/workflows/scorecard.yml

@@ -0,0 +1,78 @@
+# This workflow uses actions that are not certified by GitHub. They are provided
+# by a third-party and are governed by separate terms of service, privacy
+# policy, and support documentation.
+
+name: Scorecard supply-chain security
+on:
+  # For Branch-Protection check. Only the default branch is supported. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#branch-protection
+  branch_protection_rule:
+  # To guarantee Maintained check is occasionally updated. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#maintained
+  schedule:
+    - cron: '39 7 * * 2'
+  push:
+    branches: [ "master" ]
+
+# Declare default permissions as read only.
+permissions: read-all
+
+jobs:
+  analysis:
+    name: Scorecard analysis
+    runs-on: ubuntu-latest
+    # `publish_results: true` only works when run from the default branch. conditional can be removed if disabled.
+    if: github.event.repository.default_branch == github.ref_name || github.event_name == 'pull_request'
+    permissions:
+      # Needed to upload the results to code-scanning dashboard.
+      security-events: write
+      # Needed to publish results and get a badge (see publish_results below).
+      id-token: write
+      # Uncomment the permissions below if installing in a private repository.
+      # contents: read
+      # actions: read
+
+    steps:
+      - name: "Checkout code"
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+
+      - name: "Run analysis"
+        uses: ossf/scorecard-action@4eaacf0543bb3f2c246792bd56e8cdeffafb205a # v2.4.3
+        with:
+          results_file: results.sarif
+          results_format: sarif
+          # (Optional) "write" PAT token. Uncomment the `repo_token` line below if:
+          # - you want to enable the Branch-Protection check on a *public* repository, or
+          # - you are installing Scorecard on a *private* repository
+          # To create the PAT, follow the steps in https://github.com/ossf/scorecard-action?tab=readme-ov-file#authentication-with-fine-grained-pat-optional.
+          # repo_token: ${{ secrets.SCORECARD_TOKEN }}
+
+          # Public repositories:
+          #   - Publish results to OpenSSF REST API for easy access by consumers
+          #   - Allows the repository to include the Scorecard badge.
+          #   - See https://github.com/ossf/scorecard-action#publishing-results.
+          # For private repositories:
+          #   - `publish_results` will always be set to `false`, regardless
+          #     of the value entered here.
+          publish_results: true
+
+          # (Optional) Uncomment file_mode if you have a .gitattributes with files marked export-ignore
+          # file_mode: git
+
+      # Upload the results as artifacts (optional). Commenting out will disable uploads of run results in SARIF
+      # format to the repository Actions tab.
+      - name: "Upload artifact"
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
+        with:
+          name: SARIF file
+          path: results.sarif
+          retention-days: 5
+
+      # Upload the results to GitHub's code scanning dashboard (optional).
+      # Commenting out will disable upload of results to your repo's Code Scanning dashboard
+      - name: "Upload to code-scanning"
+        uses: github/codeql-action/upload-sarif@v4
+        with:
+          sarif_file: results.sarif

.github/workflows/snap-release.yml

@@ -7,19 +7,23 @@ on:
   # Allows you to run this workflow manually from the Actions tab
   workflow_dispatch:
 
+permissions: {}
+
 jobs:
     buildSnap:
       environment: snap
       runs-on: ubuntu-latest
+      permissions:
+        contents: read
       steps:
-        - uses: actions/checkout@v6
-        - uses: snapcore/action-build@v1
+        - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        - uses: snapcore/action-build@3bdaa03e1ba6bf59a65f84a751d943d549a54e79 # v1.3.0
           id: build
           env:
             SNAPCRAFT_STORE_CREDENTIALS: ${{ secrets.STORE_LOGIN }}
           with:
             snapcraft-args: "remote-build --launchpad-accept-public-upload"
-        - uses: snapcore/action-publish@v1
+        - uses: snapcore/action-publish@214b86e5ca036ead1668c79afb81e550e6c54d40 # v1.2.0
           env:
             SNAPCRAFT_STORE_CREDENTIALS: ${{ secrets.STORE_LOGIN }}
           with:

.github/workflows/test-yq.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - name: Get test
         id: get_value
         uses: mikefarah/yq@master

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.26.1 AS builder
+FROM golang:1.26.3@sha256:313faae491b410a35402c05d35e7518ae99103d957308e940e1ae2cfa0aac29b AS builder
 
 WORKDIR /go/src/mikefarah/yq
 
@@ -10,7 +10,7 @@ RUN ./scripts/acceptance.sh
 
 # Choose alpine as a base image to make this useful for CI, as many
 # CI tools expect an interactive shell inside the container
-FROM alpine:3 AS production
+FROM alpine:3@sha256:5b10f432ef3da1b8d4c7eb6c487f2f5a8f096bc91145e68878dd4a5019afde11 AS production
 LABEL maintainer="Mike Farah <mikefarah@users.noreply.github.com>"
 
 COPY --from=builder /go/src/mikefarah/yq/yq /usr/bin/yq

Dockerfile.dev

@@ -1,4 +1,4 @@
-FROM golang:1.26.1
+FROM golang:1.26.3@sha256:313faae491b410a35402c05d35e7518ae99103d957308e940e1ae2cfa0aac29b
 
 RUN apt-get update && \
     apt-get install -y npm && \

README.md

@@ -478,3 +478,4 @@ yq ".a.b[0].c = \"value\"" file.yaml
 - "yes", "no" were dropped as boolean values in the yaml 1.2 standard - which is the standard yq assumes.
 
 See [tips and tricks](https://mikefarah.gitbook.io/yq/usage/tips-and-tricks) for more common problems and solutions.
+

SECURITY.md

@@ -0,0 +1,26 @@
+# Security Policy
+
+## Reporting a Vulnerability
+
+Please **do not** report security vulnerabilities through public GitHub issues.
+
+Instead, use GitHub's private vulnerability reporting feature:
+👉 https://github.com/mikefarah/yq/security
+
+This allows vulnerabilities to be triaged and addressed confidentially before any public disclosure.
+
+## Scope
+
+### HTTP / TLS / Network vulnerabilities
+
+yq is a command-line YAML/JSON/TOML processor that reads from files or standard input and writes to standard output. **yq does not include any HTTP or network libraries** and makes no network connections at runtime. CVEs related to HTTP, TLS, or networking are therefore **not applicable** to yq.
+
+### Dependency version bumps
+
+yq uses [Dependabot](https://docs.github.com/en/code-security/dependabot) to automatically raise pull requests for:
+
+- Go module dependencies
+- Go toolchain version
+- Docker base images
+
+Please **do not** raise pull requests or issues solely to bump dependency or Go versions — Dependabot handles this automatically and the maintainers merge those PRs regularly.

action.yml

@@ -1,17 +1,105 @@
-name: 'yq - portable yaml processor'
-description: 'create, read, update, delete, merge, validate and do more with yaml'
+name: "yq - portable yaml processor"
+description: "create, read, update, delete, merge, validate and do more with yaml"
 branding:
   icon: command
   color: gray-dark
 inputs:
+  image:
+    description: 'Container image to run. Example: "mikefarah/yq:4-githubaction" or fully qualified "artifacts.example.com/repo/mikefarah/yq:4-githubaction".'
+    required: false
+    default: "mikefarah/yq:4-githubaction"
+  registry:
+    description: "Optional artifact repository hostname to prefix the `image`. Leave empty if your `image` already includes a registry."
+    required: false
+    default: ""
+  registry_username:
+    description: "Optional registry username for `docker login` (use with `registry_password`)."
+    required: false
+    default: ""
+  registry_password:
+    description: "Optional registry password for `docker login` (use with `registry_username`). Pass secrets via workflow `with:` from secrets."
+    required: false
+    default: ""
   cmd:
-    description: 'The Command which should be run'
+    description: "The Command which should be run"
     required: true
+runs:
+  using: "composite"
+  steps:
+    - id: pull-with-credentials
+      name: Pull image using provided credentials
+      if: ${{ inputs.registry_username && inputs.registry_password && inputs.registry }}
+      shell: bash
+      env:
+        IMAGE_INPUT: ${{ inputs.image }}
+        REGISTRY: ${{ inputs.registry }}
+        REG_USER: ${{ inputs.registry_username }}
+        REG_PASS: ${{ inputs.registry_password }}
+      run: |
+        set -euo pipefail
+        IMAGE="$IMAGE_INPUT"
+        if [ -n "$REGISTRY" ]; then
+          REG="${REGISTRY%/}"
+          IMAGE="$REG/$IMAGE"
+        fi
+        echo "Using image: $IMAGE"
+        echo "Credentials provided; attempting docker login to $REGISTRY"
+        if [ -n "$REG_PASS" ]; then
+          echo "::add-mask::$REG_PASS"
+        fi
+        echo "$REG_PASS" | docker login "$REGISTRY" --username "$REG_USER" --password-stdin
+        if docker pull "$IMAGE" >/dev/null 2>&1; then
+          echo "Image pulled successfully after login."
+        else
+          echo "Failed to pull image after login; proceeding to run (docker run may fail)."
+        fi
+
+    - id: pull-anonymous
+      name: Pull image anonymously
+      if: ${{ !(inputs.registry_username && inputs.registry_password && inputs.registry) }}
+      shell: bash
+      env:
+        IMAGE_INPUT: ${{ inputs.image }}
+        REGISTRY: ${{ inputs.registry }}
+      run: |
+        set -euo pipefail
+        IMAGE="$IMAGE_INPUT"
+        if [ -n "$REGISTRY" ]; then
+          REG="${REGISTRY%/}"
+          IMAGE="$REG/$IMAGE"
+        fi
+        echo "Using image: $IMAGE"
+        echo "No credentials provided (or registry not set); attempting anonymous pull"
+        if docker pull "$IMAGE" >/dev/null 2>&1; then
+          echo "Anonymous pull succeeded."
+        else
+          echo "Anonymous pull failed; proceeding to run (docker run may fail if auth required)."
+        fi
+
+    - id: run
+      name: Run yq container
+      shell: bash
+      env:
+        IMAGE_INPUT: ${{ inputs.image }}
+        REGISTRY: ${{ inputs.registry }}
+        CMD_INPUT: ${{ inputs.cmd }}
+      run: |
+        set -euo pipefail
+        IMAGE="$IMAGE_INPUT"
+        if [ -n "$REGISTRY" ]; then
+          REG="${REGISTRY%/}"
+          IMAGE="$REG/$IMAGE"
+        fi
+        echo "Using image: $IMAGE"
+        RC=0
+        OUTPUT=$(docker run --rm -v "$GITHUB_WORKSPACE":/work -w /work "$IMAGE" sh -lc "$CMD_INPUT" 2>&1) || RC=$?
+        echo "result<<EOF" >> $GITHUB_OUTPUT
+        echo "$OUTPUT" >> $GITHUB_OUTPUT
+        echo "EOF" >> $GITHUB_OUTPUT
+        if [ "$RC" -ne 0 ]; then
+          exit "$RC"
+        fi
 outputs:
   result:
     description: "The complete result from the yq command being run"
-runs:
-  using: 'docker'
-  image: 'docker://mikefarah/yq:4-githubaction'
-  args:
-    - ${{ inputs.cmd }}
+    value: ${{ steps.run.outputs.result }}

cmd/root.go

@@ -212,6 +212,7 @@ yq -P -oy sample.json
 
 	rootCmd.PersistentFlags().BoolVarP(&yqlib.ConfiguredSecurityPreferences.DisableEnvOps, "security-disable-env-ops", "", false, "Disable env related operations.")
 	rootCmd.PersistentFlags().BoolVarP(&yqlib.ConfiguredSecurityPreferences.DisableFileOps, "security-disable-file-ops", "", false, "Disable file related operations (e.g. load)")
+	rootCmd.PersistentFlags().BoolVarP(&yqlib.ConfiguredSecurityPreferences.EnableSystemOps, "security-enable-system-operator", "", false, "Enable system operator to allow execution of external commands.")
 
 	rootCmd.AddCommand(
 		createEvaluateSequenceCommand(),

cmd/version.go

@@ -11,7 +11,7 @@ var (
 	GitDescribe string
 
 	// Version is main version number that is being run at the moment.
-	Version = "v4.52.5"
+	Version = "v4.53.2"
 
 	// VersionPrerelease is a pre-release marker for the version. If this is "" (empty string)
 	// then it means that it is a final release. Otherwise, this is a pre-release

github-action/Dockerfile

@@ -1,4 +1,4 @@
-FROM mikefarah/yq:4
+FROM mikefarah/yq:4@sha256:603ebff15eb308a05f1c5b8b7613179cad859aed3ec9fdd04f2ef5d32345950e
 
 COPY entrypoint.sh /entrypoint.sh
 

go.mod

@@ -13,16 +13,16 @@ require (
 	github.com/hashicorp/hcl/v2 v2.24.0
 	github.com/jinzhu/copier v0.4.0
 	github.com/magiconair/properties v1.8.10
-	github.com/pelletier/go-toml/v2 v2.3.0
+	github.com/pelletier/go-toml/v2 v2.3.1
 	github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e
 	github.com/spf13/cobra v1.10.2
 	github.com/spf13/pflag v1.0.10
-	github.com/yuin/gopher-lua v1.1.1
-	github.com/zclconf/go-cty v1.18.0
-	go.yaml.in/yaml/v4 v4.0.0-rc.3
-	golang.org/x/mod v0.34.0
-	golang.org/x/net v0.52.0
-	golang.org/x/text v0.35.0
+	github.com/yuin/gopher-lua v1.1.2
+	github.com/zclconf/go-cty v1.18.1
+	go.yaml.in/yaml/v4 v4.0.0-rc.4
+	golang.org/x/mod v0.36.0
+	golang.org/x/net v0.54.0
+	golang.org/x/text v0.37.0
 )
 
 require (
@@ -34,8 +34,8 @@ require (
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mitchellh/go-wordwrap v1.0.1 // indirect
 	golang.org/x/sync v0.20.0 // indirect
-	golang.org/x/sys v0.42.0 // indirect
-	golang.org/x/tools v0.42.0 // indirect
+	golang.org/x/sys v0.44.0 // indirect
+	golang.org/x/tools v0.44.0 // indirect
 )
 
 go 1.25.0

go.sum

@@ -46,8 +46,8 @@ github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWE
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mitchellh/go-wordwrap v1.0.1 h1:TLuKupo69TCn6TQSyGxwI1EblZZEsQ0vMlAFQflz0v0=
 github.com/mitchellh/go-wordwrap v1.0.1/go.mod h1:R62XHJLzvMFRBbcrT7m7WgmE1eOyTSsCt+hzestvNj0=
-github.com/pelletier/go-toml/v2 v2.3.0 h1:k59bC/lIZREW0/iVaQR8nDHxVq8OVlIzYCOJf421CaM=
-github.com/pelletier/go-toml/v2 v2.3.0/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
+github.com/pelletier/go-toml/v2 v2.3.1 h1:MYEvvGnQjeNkRF1qUuGolNtNExTDwct51yp7olPtrEc=
+github.com/pelletier/go-toml/v2 v2.3.1/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
 github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e h1:aoZm08cpOy4WuID//EZDgcC4zIxODThtZNPirFr42+A=
 github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -61,28 +61,28 @@ github.com/spf13/pflag v1.0.10/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3A
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/yuin/gopher-lua v1.1.1 h1:kYKnWBjvbNP4XLT3+bPEwAXJx262OhaHDWDVOPjL46M=
-github.com/yuin/gopher-lua v1.1.1/go.mod h1:GBR0iDaNXjAgGg9zfCvksxSRnQx76gclCIb7kdAd1Pw=
-github.com/zclconf/go-cty v1.18.0 h1:pJ8+HNI4gFoyRNqVE37wWbJWVw43BZczFo7KUoRczaA=
-github.com/zclconf/go-cty v1.18.0/go.mod h1:qpnV6EDNgC1sns/AleL1fvatHw72j+S+nS+MJ+T2CSg=
+github.com/yuin/gopher-lua v1.1.2 h1:yF/FjE3hD65tBbt0VXLE13HWS9h34fdzJmrWRXwobGA=
+github.com/yuin/gopher-lua v1.1.2/go.mod h1:7aRmXIWl37SqRf0koeyylBEzJ+aPt8A+mmkQ4f1ntR8=
+github.com/zclconf/go-cty v1.18.1 h1:yEGE8M4iIZlyKQURZNb2SnEyZlZHUcBCnx6KF81KuwM=
+github.com/zclconf/go-cty v1.18.1/go.mod h1:qpnV6EDNgC1sns/AleL1fvatHw72j+S+nS+MJ+T2CSg=
 github.com/zclconf/go-cty-debug v0.0.0-20240509010212-0d6042c53940 h1:4r45xpDWB6ZMSMNJFMOjqrGHynW3DIBuR2H9j0ug+Mo=
 github.com/zclconf/go-cty-debug v0.0.0-20240509010212-0d6042c53940/go.mod h1:CmBdvvj3nqzfzJ6nTCIwDTPZ56aVGvDrmztiO5g3qrM=
 go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
-go.yaml.in/yaml/v4 v4.0.0-rc.3 h1:3h1fjsh1CTAPjW7q/EMe+C8shx5d8ctzZTrLcs/j8Go=
-go.yaml.in/yaml/v4 v4.0.0-rc.3/go.mod h1:aZqd9kCMsGL7AuUv/m/PvWLdg5sjJsZ4oHDEnfPPfY0=
-golang.org/x/mod v0.34.0 h1:xIHgNUUnW6sYkcM5Jleh05DvLOtwc6RitGHbDk4akRI=
-golang.org/x/mod v0.34.0/go.mod h1:ykgH52iCZe79kzLLMhyCUzhMci+nQj+0XkbXpNYtVjY=
-golang.org/x/net v0.52.0 h1:He/TN1l0e4mmR3QqHMT2Xab3Aj3L9qjbhRm78/6jrW0=
-golang.org/x/net v0.52.0/go.mod h1:R1MAz7uMZxVMualyPXb+VaqGSa3LIaUqk0eEt3w36Sw=
+go.yaml.in/yaml/v4 v4.0.0-rc.4 h1:UP4+v6fFrBIb1l934bDl//mmnoIZEDK0idg1+AIvX5U=
+go.yaml.in/yaml/v4 v4.0.0-rc.4/go.mod h1:aZqd9kCMsGL7AuUv/m/PvWLdg5sjJsZ4oHDEnfPPfY0=
+golang.org/x/mod v0.36.0 h1:JJjpVx6myfUsUdAzZuOSTTmRE0PfZeNWzzvKrP7amb4=
+golang.org/x/mod v0.36.0/go.mod h1:moc6ELqsWcOw5Ef3xVprK5ul/MvtVvkIXLziUOICjUQ=
+golang.org/x/net v0.54.0 h1:2zJIZAxAHV/OHCDTCOHAYehQzLfSXuf/5SoL/Dv6w/w=
+golang.org/x/net v0.54.0/go.mod h1:Sj4oj8jK6XmHpBZU/zWHw3BV3abl4Kvi+Ut7cQcY+cQ=
 golang.org/x/sync v0.20.0 h1:e0PTpb7pjO8GAtTs2dQ6jYa5BWYlMuX047Dco/pItO4=
 golang.org/x/sync v0.20.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.42.0 h1:omrd2nAlyT5ESRdCLYdm3+fMfNFE/+Rf4bDIQImRJeo=
-golang.org/x/sys v0.42.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
-golang.org/x/text v0.35.0 h1:JOVx6vVDFokkpaq1AEptVzLTpDe9KGpj5tR4/X+ybL8=
-golang.org/x/text v0.35.0/go.mod h1:khi/HExzZJ2pGnjenulevKNX1W67CUy0AsXcNubPGCA=
-golang.org/x/tools v0.42.0 h1:uNgphsn75Tdz5Ji2q36v/nsFSfR/9BRFvqhGBaJGd5k=
-golang.org/x/tools v0.42.0/go.mod h1:Ma6lCIwGZvHK6XtgbswSoWroEkhugApmsXyrUmBhfr0=
+golang.org/x/sys v0.44.0 h1:ildZl3J4uzeKP07r2F++Op7E9B29JRUy+a27EibtBTQ=
+golang.org/x/sys v0.44.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
+golang.org/x/text v0.37.0 h1:Cqjiwd9eSg8e0QAkyCaQTNHFIIzWtidPahFWR83rTrc=
+golang.org/x/text v0.37.0/go.mod h1:a5sjxXGs9hsn/AJVwuElvCAo9v8QYLzvavO5z2PiM38=
+golang.org/x/tools v0.44.0 h1:UP4ajHPIcuMjT1GqzDWRlalUEoY+uzoZKnhOjbIPD2c=
+golang.org/x/tools v0.44.0/go.mod h1:KA0AfVErSdxRZIsOVipbv3rQhVXTnlU6UhKxHd1seDI=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

pkg/yqlib/candidate_node.go

@@ -27,6 +27,22 @@ const (
 	FlowStyle
 )
 
+// EncodeHint controls how a mapping node is serialised by format-specific encoders
+// that distinguish between inline and block/section representations (e.g. TOML, HCL).
+type EncodeHint int
+
+const (
+	// EncodeHintDefault lets the encoder choose the representation (e.g. TOML block
+	// mappings default to [section] headers).
+	EncodeHintDefault EncodeHint = iota
+	// EncodeHintSeparateBlock forces the node to be emitted as a separate block or
+	// table-section header (used by TOML [section] and HCL block decoders).
+	EncodeHintSeparateBlock
+	// EncodeHintInline forces the node to be emitted as an inline / flow table
+	// (used by TOML inline-table decoder and TOML encoder).
+	EncodeHintInline
+)
+
 func createStringScalarNode(stringValue string) *CandidateNode {
 	var node = &CandidateNode{Kind: ScalarNode}
 	node.Value = stringValue
@@ -97,9 +113,9 @@ type CandidateNode struct {
 	// (e.g. top level cross document merge). This property does not propagate to child nodes.
 	EvaluateTogether bool
 	IsMapKey         bool
-	// For formats like HCL and TOML: indicates that child entries should be emitted as separate blocks/tables
-	// rather than consolidated into nested mappings (default behaviour)
-	EncodeSeparate bool
+	// EncodeHint controls how a mapping node is serialised by format-specific encoders
+	// (e.g. TOML, HCL) that support both inline and block/section representations.
+	EncodeHint EncodeHint
 }
 
 func (n *CandidateNode) CreateChild() *CandidateNode {
@@ -411,7 +427,7 @@ func (n *CandidateNode) doCopy(cloneContent bool) *CandidateNode {
 		EvaluateTogether: n.EvaluateTogether,
 		IsMapKey:         n.IsMapKey,
 
-		EncodeSeparate: n.EncodeSeparate,
+		EncodeHint: n.EncodeHint,
 	}
 
 	if cloneContent {
@@ -465,8 +481,8 @@ func (n *CandidateNode) UpdateAttributesFrom(other *CandidateNode, prefs assignP
 		n.Anchor = other.Anchor
 	}
 
-	// Preserve EncodeSeparate flag for format-specific encoding hints
-	n.EncodeSeparate = other.EncodeSeparate
+	// Preserve EncodeHint for format-specific encoding hints
+	n.EncodeHint = other.EncodeHint
 
 	// merge will pickup the style of the new thing
 	// when autocreating nodes

pkg/yqlib/candidate_node_json.go

@@ -7,6 +7,9 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"math"
+	"strconv"
+	"strings"
 
 	"github.com/goccy/go-json"
 )
@@ -140,6 +143,12 @@ func (o *CandidateNode) MarshalJSON() ([]byte, error) {
 		return buf.Bytes(), err
 	case ScalarNode:
 		log.Debugf("MarshalJSON ScalarNode")
+		if o.guessTagFromCustomType() == "!!float" {
+			if raw, ok := jsonFloatLiteral(o.Value); ok {
+				buf.WriteString(raw)
+				return buf.Bytes(), nil
+			}
+		}
 		value, err := o.GetValueRep()
 		if err != nil {
 			return buf.Bytes(), err
@@ -177,3 +186,85 @@ func (o *CandidateNode) MarshalJSON() ([]byte, error) {
 		return buf.Bytes(), err
 	}
 }
+
+// jsonFloatLiteral returns a JSON-shaped representation of a YAML !!float scalar
+// value, preserving the original textual form (e.g. "50.0" stays "50.0") whenever
+// possible. The second return value is false when the value cannot be safely
+// rendered as a JSON number (e.g. ".inf", ".nan", or anything that parses to a
+// non-finite float); callers should fall back to the normal encoding path in
+// that case, which preserves the existing behaviour for those inputs.
+func jsonFloatLiteral(raw string) (string, bool) {
+	if raw == "" {
+		return "", false
+	}
+	f, err := strconv.ParseFloat(raw, 64)
+	if err != nil {
+		return "", false
+	}
+	if math.IsInf(f, 0) || math.IsNaN(f) {
+		return "", false
+	}
+	if isJSONNumberLiteral(raw) {
+		return raw, true
+	}
+	formatted := strconv.FormatFloat(f, 'f', -1, 64)
+	if !strings.ContainsAny(formatted, ".eE") {
+		formatted += ".0"
+	}
+	return formatted, true
+}
+
+// isJSONNumberLiteral reports whether s is already a valid JSON number literal
+// representing a fractional value (i.e. contains a "." or an exponent), so it
+// can be emitted verbatim without round-tripping through a float64.
+func isJSONNumberLiteral(s string) bool {
+	if s == "" {
+		return false
+	}
+	i := 0
+	if s[i] == '-' {
+		i++
+		if i == len(s) {
+			return false
+		}
+	}
+	// integer part: 0 or [1-9][0-9]*
+	if s[i] == '0' {
+		i++
+	} else if s[i] >= '1' && s[i] <= '9' {
+		for i < len(s) && s[i] >= '0' && s[i] <= '9' {
+			i++
+		}
+	} else {
+		return false
+	}
+	hasFraction := false
+	if i < len(s) && s[i] == '.' {
+		hasFraction = true
+		i++
+		if i == len(s) || s[i] < '0' || s[i] > '9' {
+			return false
+		}
+		for i < len(s) && s[i] >= '0' && s[i] <= '9' {
+			i++
+		}
+	}
+	hasExponent := false
+	if i < len(s) && (s[i] == 'e' || s[i] == 'E') {
+		hasExponent = true
+		i++
+		if i < len(s) && (s[i] == '+' || s[i] == '-') {
+			i++
+		}
+		if i == len(s) || s[i] < '0' || s[i] > '9' {
+			return false
+		}
+		for i < len(s) && s[i] >= '0' && s[i] <= '9' {
+			i++
+		}
+	}
+	if i != len(s) {
+		return false
+	}
+	return hasFraction || hasExponent
+}

pkg/yqlib/decoder_hcl.go

@@ -226,7 +226,7 @@ func addBlockToMapping(parent *CandidateNode, block *hclsyntax.Block, src []byte
 		// Mark the type node if there are multiple blocks of this type at this level
 		// This tells the encoder to emit them as separate blocks rather than consolidating them
 		if isMultipleBlocksOfType {
-			typeNode.EncodeSeparate = true
+			typeNode.EncodeHint = EncodeHintSeparateBlock
 		}
 	}
 	current = typeNode

pkg/yqlib/decoder_properties.go

@@ -16,10 +16,11 @@ type propertiesDecoder struct {
 	reader   io.Reader
 	finished bool
 	d        DataTreeNavigator
+	prefs    PropertiesPreferences
 }
 
 func NewPropertiesDecoder() Decoder {
-	return &propertiesDecoder{d: NewDataTreeNavigator(), finished: false}
+	return &propertiesDecoder{d: NewDataTreeNavigator(), finished: false, prefs: ConfiguredPropertiesPreferences.Copy()}
 }
 
 func (dec *propertiesDecoder) Init(reader io.Reader) error {
@@ -28,20 +29,56 @@ func (dec *propertiesDecoder) Init(reader io.Reader) error {
 	return nil
 }
 
-func parsePropKey(key string) []interface{} {
+func parsePropKey(key string, prefs PropertiesPreferences) []interface{} {
 	pathStrArray := strings.Split(key, ".")
-	path := make([]interface{}, len(pathStrArray))
-	for i, pathStr := range pathStrArray {
-		num, err := strconv.ParseInt(pathStr, 10, 32)
-		if err == nil {
-			path[i] = num
-		} else {
-			path[i] = pathStr
-		}
+	path := make([]interface{}, 0, len(pathStrArray))
+	for _, pathStr := range pathStrArray {
+		path = appendPropKeySegment(path, pathStr, prefs.UseArrayBrackets)
 	}
 	return path
 }
 
+func appendPropKeySegment(path []interface{}, segment string, useArrayBrackets bool) []interface{} {
+	if useArrayBrackets && strings.Contains(segment, "[") {
+		bracketPath, ok := parsePropKeyArrayBracketSegment(segment)
+		if ok {
+			return append(path, bracketPath...)
+		}
+	}
+
+	num, err := strconv.ParseInt(segment, 10, 32)
+	if err == nil {
+		return append(path, num)
+	}
+	return append(path, segment)
+}
+
+func parsePropKeyArrayBracketSegment(segment string) ([]interface{}, bool) {
+	path := []interface{}{}
+	bracketIndex := strings.Index(segment, "[")
+	if bracketIndex > 0 {
+		path = append(path, segment[:bracketIndex])
+	}
+
+	remaining := segment[bracketIndex:]
+	for remaining != "" {
+		if !strings.HasPrefix(remaining, "[") {
+			return nil, false
+		}
+		closingBracket := strings.Index(remaining, "]")
+		if closingBracket < 0 {
+			return nil, false
+		}
+		arrayIndex, err := strconv.ParseInt(remaining[1:closingBracket], 10, 32)
+		if err != nil {
+			return nil, false
+		}
+		path = append(path, arrayIndex)
+		remaining = remaining[closingBracket+1:]
+	}
+	return path, true
+}
+
 func (dec *propertiesDecoder) processComment(c string) string {
 	if c == "" {
 		return ""
@@ -75,7 +112,7 @@ func (dec *propertiesDecoder) applyPropertyComments(context Context, path []inte
 
 func (dec *propertiesDecoder) applyProperty(context Context, properties *properties.Properties, key string) error {
 	value, _ := properties.Get(key)
-	path := parsePropKey(key)
+	path := parsePropKey(key, dec.prefs)
 
 	propertyComments := properties.GetComments(key)
 	if len(propertyComments) > 0 {

pkg/yqlib/decoder_toml.go

@@ -150,9 +150,10 @@ func (dec *tomlDecoder) createInlineTableMap(tomlNode *toml.Node) (*CandidateNod
 	}
 
 	return &CandidateNode{
-		Kind:    MappingNode,
-		Tag:     "!!map",
-		Content: content,
+		Kind:       MappingNode,
+		Tag:        "!!map",
+		EncodeHint: EncodeHintInline,
+		Content:    content,
 	}, nil
 }
 
@@ -345,10 +346,10 @@ func (dec *tomlDecoder) processTable(currentNode *toml.Node) (bool, error) {
 	}
 
 	tableNodeValue := &CandidateNode{
-		Kind:           MappingNode,
-		Tag:            "!!map",
-		Content:        make([]*CandidateNode, 0),
-		EncodeSeparate: true,
+		Kind:       MappingNode,
+		Tag:        "!!map",
+		Content:    make([]*CandidateNode, 0),
+		EncodeHint: EncodeHintSeparateBlock,
 	}
 
 	// Attach pending head comments to the table
@@ -442,9 +443,9 @@ func (dec *tomlDecoder) processArrayTable(currentNode *toml.Node) (bool, error)
 	hasValue := dec.parser.NextExpression()
 
 	tableNodeValue := &CandidateNode{
-		Kind:           MappingNode,
-		Tag:            "!!map",
-		EncodeSeparate: true,
+		Kind:       MappingNode,
+		Tag:        "!!map",
+		EncodeHint: EncodeHintSeparateBlock,
 	}
 
 	// Attach pending head comments to the array table

pkg/yqlib/doc/operators/headers/slice-array.md

@@ -1,5 +1,5 @@
-# Slice/Splice Array
+# Slice Array or String
 
-The slice array operator takes an array as input and returns a subarray. Like the `jq` equivalent, `.[10:15]` will return an array of length 5, starting from index 10 inclusive, up to index 15 exclusive. Negative numbers count backwards from the end of the array.
+The slice operator works on both arrays and strings. Like the `jq` equivalent, `.[10:15]` will return a subarray (or substring) of length 5, starting from index 10 inclusive, up to index 15 exclusive. Negative numbers count backwards from the end of the array or string.
 
-You may leave out the first or second number, which will refer to the start or end of the array respectively.
+You may leave out the first or second number, which will refer to the start or end of the array or string respectively.

pkg/yqlib/doc/operators/headers/system-operators.md

@@ -0,0 +1,27 @@
+# System Operators
+
+The `system` operator allows you to run an external command and use its output as a value in your expression.
+
+**Security warning**: The system operator is disabled by default. You must explicitly pass `--security-enable-system-operator` to use it.
+
+**Note:** When enabled, the system operator can replicate the functionality of `env` and `load`
+operators via external commands. Enabling it effectively overrides `--security-disable-env-ops`
+and `--security-disable-file-ops`.
+
+## Usage
+
+```bash
+yq --security-enable-system-operator --null-input '.field = system("command"; "arg1")'
+```
+
+The operator takes:
+- A command string (required)
+- An argument (or an array of arguments), separated from the command by `;` (optional)
+
+The current matched node's value is serialised and piped to the command via stdin. The command's stdout (with trailing newline stripped) is returned as a string.
+
+## Disabling the system operator
+
+The system operator is disabled by default. When disabled, an error is returned instead of running the command, consistent with `--security-disable-env-ops` and `--security-disable-file-ops`.
+
+Use `--security-enable-system-operator` flag to enable it.

pkg/yqlib/doc/operators/slice-array.md

@@ -1,8 +1,8 @@
-# Slice/Splice Array
+# Slice Array or String
 
-The slice array operator takes an array as input and returns a subarray. Like the `jq` equivalent, `.[10:15]` will return an array of length 5, starting from index 10 inclusive, up to index 15 exclusive. Negative numbers count backwards from the end of the array.
+The slice operator works on both arrays and strings. Like the `jq` equivalent, `.[10:15]` will return a subarray (or substring) of length 5, starting from index 10 inclusive, up to index 15 exclusive. Negative numbers count backwards from the end of the array or string.
 
-You may leave out the first or second number, which will refer to the start or end of the array respectively.
+You may leave out the first or second number, which will refer to the start or end of the array or string respectively.
 
 ## Slicing arrays
 Given a sample.yml file of:
@@ -103,3 +103,81 @@ will output
 - cow
 ```
 
+## Slicing strings
+Given a sample.yml file of:
+```yaml
+country: Australia
+```
+then
+```bash
+yq '.country[0:5]' sample.yml
+```
+will output
+```yaml
+Austr
+```
+
+## Slicing strings - without the second number
+Finishes at the end of the string
+
+Given a sample.yml file of:
+```yaml
+country: Australia
+```
+then
+```bash
+yq '.country[5:]' sample.yml
+```
+will output
+```yaml
+alia
+```
+
+## Slicing strings - without the first number
+Starts from the start of the string
+
+Given a sample.yml file of:
+```yaml
+country: Australia
+```
+then
+```bash
+yq '.country[:5]' sample.yml
+```
+will output
+```yaml
+Austr
+```
+
+## Slicing strings - use negative numbers to count backwards from the end
+Negative indices count from the end of the string
+
+Given a sample.yml file of:
+```yaml
+country: Australia
+```
+then
+```bash
+yq '.country[-5:]' sample.yml
+```
+will output
+```yaml
+ralia
+```
+
+## Slicing strings - Unicode
+Indices are rune-based, so multi-byte characters are handled correctly
+
+Given a sample.yml file of:
+```yaml
+greeting: héllo
+```
+then
+```bash
+yq '.greeting[1:3]' sample.yml
+```
+will output
+```yaml
+él
+```
+

pkg/yqlib/doc/operators/system-operators.md

@@ -0,0 +1,76 @@
+# System Operators
+
+The `system` operator allows you to run an external command and use its output as a value in your expression.
+
+**Security warning**: The system operator is disabled by default. You must explicitly pass `--security-enable-system-operator` to use it.
+
+**Note:** When enabled, the system operator can replicate the functionality of `env` and `load`
+operators via external commands. Enabling it effectively overrides `--security-disable-env-ops`
+and `--security-disable-file-ops`.
+
+## Usage
+
+```bash
+yq --security-enable-system-operator --null-input '.field = system("command"; "arg1")'
+```
+
+The operator takes:
+- A command string (required)
+- An argument (or an array of arguments), separated from the command by `;` (optional)
+
+The current matched node's value is serialised and piped to the command via stdin. The command's stdout (with trailing newline stripped) is returned as a string.
+
+## Disabling the system operator
+
+The system operator is disabled by default. When disabled, an error is returned instead of running the command, consistent with `--security-disable-env-ops` and `--security-disable-file-ops`.
+
+Use `--security-enable-system-operator` flag to enable it.
+
+## system operator returns error when disabled
+Use `--security-enable-system-operator` to enable the system operator.
+
+Given a sample.yml file of:
+```yaml
+country: Australia
+```
+then
+```bash
+yq '.country = system("/usr/bin/echo"; "test")' sample.yml
+```
+will output
+```bash
+Error: system operations are disabled, use --security-enable-system-operator to enable
+```
+
+## Run a command with an argument
+Use `--security-enable-system-operator` to enable the system operator.
+
+Given a sample.yml file of:
+```yaml
+country: Australia
+```
+then
+```bash
+yq --security-enable-system-operator '.country = system("/usr/bin/echo"; "test")' sample.yml
+```
+will output
+```yaml
+country: test
+```
+
+## Run a command without arguments
+Omit the semicolon and args to run the command with no extra arguments.
+
+Given a sample.yml file of:
+```yaml
+a: hello
+```
+then
+```bash
+yq --security-enable-system-operator '.a = system("/usr/bin/echo")' sample.yml
+```
+will output
+```yaml
+a: ""
+```
+

pkg/yqlib/doc/usage/convert.md

@@ -125,6 +125,22 @@ will output
 {"whatever":"cat"}
 ```
 
+## Encode json: preserve floats with trailing zero
+Whole-number floats keep their decimal point so downstream consumers see a JSON number with a fractional part (matches Go's encoding/json, Python's json, and jq).
+
+Given a sample.yml file of:
+```yaml
+percentiles: [50.0, 95.0, 99.0, 99.9]
+```
+then
+```bash
+yq -o=json -I=0 '.' sample.yml
+```
+will output
+```json
+{"percentiles":[50.0,95.0,99.0,99.9]}
+```
+
 ## Roundtrip JSON Lines / NDJSON
 Given a sample.json file of:
 ```json

pkg/yqlib/doc/usage/toml.md

@@ -384,3 +384,20 @@ ip = "10.0.0.2"
 role = "backend"
 ```
 
+## Encode: Simple mapping produces table section
+Given a sample.yml file of:
+```yaml
+arg:
+  hello: foo
+
+```
+then
+```bash
+yq -o toml '.' sample.yml
+```
+will output
+```toml
+[arg]
+hello = "foo"
+```
+

pkg/yqlib/encoder_hcl.go

@@ -449,8 +449,8 @@ func (he *hclEncoder) encodeBlockIfMapping(body *hclwrite.Body, key string, valu
 		return false
 	}
 
-	// If EncodeSeparate is set, emit children as separate blocks regardless of label extraction
-	if valueNode.EncodeSeparate {
+	// If EncodeHintSeparateBlock is set, emit children as separate blocks regardless of label extraction
+	if valueNode.EncodeHint == EncodeHintSeparateBlock {
 		if handled, _ := he.encodeMappingChildrenAsBlocks(body, key, valueNode); handled {
 			return true
 		}
@@ -537,9 +537,9 @@ func (he *hclEncoder) encodeMappingChildrenAsBlocks(body *hclwrite.Body, blockTy
 		return false, nil
 	}
 
-	// Only emit as separate blocks if EncodeSeparate is true
+	// Only emit as separate blocks if EncodeHintSeparateBlock is set
 	// This allows the encoder to respect the original block structure preserved by the decoder
-	if !valueNode.EncodeSeparate {
+	if valueNode.EncodeHint != EncodeHintSeparateBlock {
 		return false, nil
 	}
 

pkg/yqlib/encoder_toml.go

@@ -69,6 +69,27 @@ func (te *tomlEncoder) CanHandleAliases() bool {
 
 // ---- helpers ----
 
+// tomlKey returns the key quoted if it contains characters that are not valid
+// in a TOML bare key. TOML bare keys may only contain ASCII letters, ASCII
+// digits, underscores, and dashes.
+func tomlKey(key string) string {
+	for _, r := range key {
+		if (r < 'A' || r > 'Z') && (r < 'a' || r > 'z') && (r < '0' || r > '9') && r != '_' && r != '-' {
+			return fmt.Sprintf("%q", key)
+		}
+	}
+	return key
+}
+
+// tomlDottedKey joins path components, quoting any that require it.
+func tomlDottedKey(path []string) string {
+	parts := make([]string, len(path))
+	for i, p := range path {
+		parts[i] = tomlKey(p)
+	}
+	return strings.Join(parts, ".")
+}
+
 func (te *tomlEncoder) writeComment(w io.Writer, comment string) error {
 	if comment == "" {
 		return nil
@@ -111,12 +132,23 @@ func (te *tomlEncoder) encodeRootMapping(w io.Writer, node *CandidateNode) error
 		}
 	}
 
-	// Preserve existing order by iterating Content
 	for i := 0; i < len(node.Content); i += 2 {
 		keyNode := node.Content[i]
 		valNode := node.Content[i+1]
-		if err := te.encodeTopLevelEntry(w, []string{keyNode.Value}, valNode); err != nil {
-			return err
+		if isTomlAttribute(valNode) {
+			if err := te.encodeTopLevelEntry(w, []string{keyNode.Value}, valNode); err != nil {
+				return err
+			}
+		}
+	}
+
+	for i := 0; i < len(node.Content); i += 2 {
+		keyNode := node.Content[i]
+		valNode := node.Content[i+1]
+		if !isTomlAttribute(valNode) {
+			if err := te.encodeTopLevelEntry(w, []string{keyNode.Value}, valNode); err != nil {
+				return err
+			}
 		}
 	}
 	return nil
@@ -148,9 +180,15 @@ func (te *tomlEncoder) encodeTopLevelEntry(w io.Writer, path []string, node *Can
 		}
 		if allMaps {
 			key := path[len(path)-1]
+			quotedKey := tomlKey(key)
+			if te.wroteRootAttr {
+				if _, err := w.Write([]byte("\n")); err != nil {
+					return err
+				}
+				te.wroteRootAttr = false
+			}
 			for _, it := range node.Content {
-				// [[key]] then body
-				if _, err := w.Write([]byte("[[" + key + "]]\n")); err != nil {
+				if _, err := w.Write([]byte("[[" + quotedKey + "]]\n")); err != nil {
 					return err
 				}
 				if err := te.encodeMappingBodyWithPath(w, []string{key}, it); err != nil {
@@ -162,12 +200,12 @@ func (te *tomlEncoder) encodeTopLevelEntry(w io.Writer, path []string, node *Can
 		// Regular array attribute
 		return te.writeArrayAttribute(w, path[len(path)-1], node)
 	case MappingNode:
-		// Inline table if not EncodeSeparate, else emit separate tables/arrays of tables for children under this path
-		if !node.EncodeSeparate {
-			// If children contain mappings or arrays of mappings, prefer separate sections
-			if te.hasEncodeSeparateChild(node) || te.hasStructuralChildren(node) {
-				return te.encodeSeparateMapping(w, path, node)
-			}
+		// Use inline table syntax only for nodes explicitly marked as TOML inline tables.
+		// YAML flow-style mappings are not treated as inline tables; the FlowStyle attribute
+		// is a YAML-specific rendering hint and should not affect TOML output. This ensures
+		// that auto-detected JSON input (parsed as YAML flow style) produces readable table
+		// sections, consistent with explicitly parsed JSON input.
+		if node.EncodeHint == EncodeHintInline {
 			return te.writeInlineTableAttribute(w, path[len(path)-1], node)
 		}
 		return te.encodeSeparateMapping(w, path, node)
@@ -176,7 +214,30 @@ func (te *tomlEncoder) encodeTopLevelEntry(w io.Writer, path []string, node *Can
 	}
 }
 
+func isTomlArrayOfTables(seq *CandidateNode) bool {
+	if len(seq.Content) == 0 {
+		return false
+	}
+	for _, it := range seq.Content {
+		if it.Kind != MappingNode || it.EncodeHint == EncodeHintInline {
+			return false
+		}
+	}
+	return true
+}
+
+func isTomlAttribute(node *CandidateNode) bool {
+	if node.Kind == ScalarNode {
+		return true
+	}
+	return node.Kind == SequenceNode && !isTomlArrayOfTables(node)
+}
+
 func (te *tomlEncoder) writeAttribute(w io.Writer, key string, value *CandidateNode) error {
+	if value.Tag == "!!null" {
+		return nil
+	}
+
 	te.wroteRootAttr = true // Mark that we wrote a root attribute
 
 	// Write head comment before the attribute
@@ -185,7 +246,7 @@ func (te *tomlEncoder) writeAttribute(w io.Writer, key string, value *CandidateN
 	}
 
 	// Write the attribute
-	line := key + " = " + te.formatScalar(value)
+	line := tomlKey(key) + " = " + te.formatScalar(value)
 
 	// Add line comment if present
 	if value.LineComment != "" {
@@ -210,7 +271,7 @@ func (te *tomlEncoder) writeArrayAttribute(w io.Writer, key string, seq *Candida
 
 	// Handle empty arrays
 	if len(seq.Content) == 0 {
-		line := key + " = []"
+		line := tomlKey(key) + " = []"
 		if seq.LineComment != "" {
 			lineComment := strings.TrimSpace(seq.LineComment)
 			if !strings.HasPrefix(lineComment, "#") {
@@ -233,7 +294,7 @@ func (te *tomlEncoder) writeArrayAttribute(w io.Writer, key string, seq *Candida
 
 	if hasElementComments {
 		// Write multiline array format with comments
-		if _, err := w.Write([]byte(key + " = [\n")); err != nil {
+		if _, err := w.Write([]byte(tomlKey(key) + " = [\n")); err != nil {
 			return err
 		}
 
@@ -324,7 +385,7 @@ func (te *tomlEncoder) writeArrayAttribute(w io.Writer, key string, seq *Candida
 		}
 	}
 
-	line := key + " = [" + strings.Join(items, ", ") + "]"
+	line := tomlKey(key) + " = [" + strings.Join(items, ", ") + "]"
 
 	// Add line comment if present
 	if seq.LineComment != "" {
@@ -372,21 +433,24 @@ func (te *tomlEncoder) mappingToInlineTable(m *CandidateNode) (string, error) {
 		v := m.Content[i+1]
 		switch v.Kind {
 		case ScalarNode:
-			parts = append(parts, fmt.Sprintf("%s = %s", k, te.formatScalar(v)))
+			if v.Tag == "!!null" {
+				continue
+			}
+			parts = append(parts, fmt.Sprintf("%s = %s", tomlKey(k), te.formatScalar(v)))
 		case SequenceNode:
 			// inline array in inline table
 			arr, err := te.sequenceToInlineArray(v)
 			if err != nil {
 				return "", err
 			}
-			parts = append(parts, fmt.Sprintf("%s = %s", k, arr))
+			parts = append(parts, fmt.Sprintf("%s = %s", tomlKey(k), arr))
 		case MappingNode:
 			// nested inline table
 			inline, err := te.mappingToInlineTable(v)
 			if err != nil {
 				return "", err
 			}
-			parts = append(parts, fmt.Sprintf("%s = %s", k, inline))
+			parts = append(parts, fmt.Sprintf("%s = %s", tomlKey(k), inline))
 		default:
 			return "", fmt.Errorf("unsupported inline table value kind: %v", v.Kind)
 		}
@@ -399,7 +463,7 @@ func (te *tomlEncoder) writeInlineTableAttribute(w io.Writer, key string, m *Can
 	if err != nil {
 		return err
 	}
-	_, err = w.Write([]byte(key + " = " + inline + "\n"))
+	_, err = w.Write([]byte(tomlKey(key) + " = " + inline + "\n"))
 	return err
 }
 
@@ -421,7 +485,7 @@ func (te *tomlEncoder) writeTableHeader(w io.Writer, path []string, m *Candidate
 	}
 
 	// Write table header [a.b.c]
-	header := "[" + strings.Join(path, ".") + "]\n"
+	header := "[" + tomlDottedKey(path) + "]\n"
 	_, err := w.Write([]byte(header))
 	return err
 }
@@ -429,24 +493,21 @@ func (te *tomlEncoder) writeTableHeader(w io.Writer, path []string, m *Candidate
 // encodeSeparateMapping handles a mapping that should be encoded as table sections.
 // It emits the table header for this mapping if it has any content, then processes children.
 func (te *tomlEncoder) encodeSeparateMapping(w io.Writer, path []string, m *CandidateNode) error {
-	// Check if this mapping has any non-mapping, non-array-of-tables children (i.e., attributes)
+	// Check if this mapping has any non-mapping, non-array-of-tables children (i.e., attributes).
+	// Inline mapping children also count as attributes since they render as key = { ... }.
 	hasAttrs := false
 	for i := 0; i < len(m.Content); i += 2 {
 		v := m.Content[i+1]
-		if v.Kind == ScalarNode {
+		if v.Kind == ScalarNode && v.Tag != "!!null" {
+			hasAttrs = true
+			break
+		}
+		if v.Kind == MappingNode && v.EncodeHint == EncodeHintInline {
 			hasAttrs = true
 			break
 		}
 		if v.Kind == SequenceNode {
-			// Check if it's NOT an array of tables
-			allMaps := true
-			for _, it := range v.Content {
-				if it.Kind != MappingNode {
-					allMaps = false
-					break
-				}
-			}
-			if !allMaps {
+			if !isTomlArrayOfTables(v) {
 				hasAttrs = true
 				break
 			}
@@ -464,31 +525,26 @@ func (te *tomlEncoder) encodeSeparateMapping(w io.Writer, path []string, m *Cand
 		return nil
 	}
 
-	// No attributes, just nested structures - process children
+	// No attributes, just nested table structures - process children recursively
 	for i := 0; i < len(m.Content); i += 2 {
 		k := m.Content[i].Value
 		v := m.Content[i+1]
 		switch v.Kind {
 		case MappingNode:
-			// Emit [path.k]
 			newPath := append(append([]string{}, path...), k)
-			if err := te.writeTableHeader(w, newPath, v); err != nil {
-				return err
-			}
-			if err := te.encodeMappingBodyWithPath(w, newPath, v); err != nil {
+			if err := te.encodeSeparateMapping(w, newPath, v); err != nil {
 				return err
 			}
 		case SequenceNode:
 			// If sequence of maps, emit [[path.k]] per element
-			allMaps := true
-			for _, it := range v.Content {
-				if it.Kind != MappingNode {
-					allMaps = false
-					break
+			if isTomlArrayOfTables(v) {
+				key := tomlDottedKey(append(append([]string{}, path...), k))
+				if te.wroteRootAttr {
+					if _, err := w.Write([]byte("\n")); err != nil {
+						return err
+					}
+					te.wroteRootAttr = false
 				}
-			}
-			if allMaps {
-				key := strings.Join(append(append([]string{}, path...), k), ".")
 				for _, it := range v.Content {
 					if _, err := w.Write([]byte("[[" + key + "]]\n")); err != nil {
 						return err
@@ -513,42 +569,9 @@ func (te *tomlEncoder) encodeSeparateMapping(w io.Writer, path []string, m *Cand
 	return nil
 }
 
-func (te *tomlEncoder) hasEncodeSeparateChild(m *CandidateNode) bool {
-	for i := 0; i < len(m.Content); i += 2 {
-		v := m.Content[i+1]
-		if v.Kind == MappingNode && v.EncodeSeparate {
-			return true
-		}
-	}
-	return false
-}
-
-func (te *tomlEncoder) hasStructuralChildren(m *CandidateNode) bool {
-	for i := 0; i < len(m.Content); i += 2 {
-		v := m.Content[i+1]
-		// Only consider it structural if mapping has EncodeSeparate or is non-empty
-		if v.Kind == MappingNode && v.EncodeSeparate {
-			return true
-		}
-		if v.Kind == SequenceNode {
-			allMaps := true
-			for _, it := range v.Content {
-				if it.Kind != MappingNode {
-					allMaps = false
-					break
-				}
-			}
-			if allMaps {
-				return true
-			}
-		}
-	}
-	return false
-}
-
 // encodeMappingBodyWithPath encodes attributes and nested arrays of tables using full dotted path context
 func (te *tomlEncoder) encodeMappingBodyWithPath(w io.Writer, path []string, m *CandidateNode) error {
-	// First, attributes (scalars and non-map arrays)
+	// First, attributes (scalars, inline mappings, and non-map arrays)
 	for i := 0; i < len(m.Content); i += 2 {
 		k := m.Content[i].Value
 		v := m.Content[i+1]
@@ -557,15 +580,14 @@ func (te *tomlEncoder) encodeMappingBodyWithPath(w io.Writer, path []string, m *
 			if err := te.writeAttribute(w, k, v); err != nil {
 				return err
 			}
-		case SequenceNode:
-			allMaps := true
-			for _, it := range v.Content {
-				if it.Kind != MappingNode {
-					allMaps = false
-					break
+		case MappingNode:
+			if v.EncodeHint == EncodeHintInline {
+				if err := te.writeInlineTableAttribute(w, k, v); err != nil {
+					return err
 				}
 			}
-			if !allMaps {
+		case SequenceNode:
+			if !isTomlArrayOfTables(v) {
 				if err := te.writeArrayAttribute(w, k, v); err != nil {
 					return err
 				}
@@ -578,15 +600,8 @@ func (te *tomlEncoder) encodeMappingBodyWithPath(w io.Writer, path []string, m *
 		k := m.Content[i].Value
 		v := m.Content[i+1]
 		if v.Kind == SequenceNode {
-			allMaps := true
-			for _, it := range v.Content {
-				if it.Kind != MappingNode {
-					allMaps = false
-					break
-				}
-			}
-			if allMaps {
-				dotted := strings.Join(append(append([]string{}, path...), k), ".")
+			if isTomlArrayOfTables(v) {
+				dotted := tomlDottedKey(append(append([]string{}, path...), k))
 				for _, it := range v.Content {
 					if _, err := w.Write([]byte("[[" + dotted + "]]\n")); err != nil {
 						return err
@@ -599,12 +614,14 @@ func (te *tomlEncoder) encodeMappingBodyWithPath(w io.Writer, path []string, m *
 		}
 	}
 
-	// Finally, child mappings that are not marked EncodeSeparate get inlined as attributes
+	// Finally, child mappings: inline-hint ones were emitted above as attributes,
+	// while all others are emitted as separate sub-table sections.
 	for i := 0; i < len(m.Content); i += 2 {
 		k := m.Content[i].Value
 		v := m.Content[i+1]
-		if v.Kind == MappingNode && !v.EncodeSeparate {
-			if err := te.writeInlineTableAttribute(w, k, v); err != nil {
+		if v.Kind == MappingNode && v.EncodeHint != EncodeHintInline {
+			subPath := append(append([]string{}, path...), k)
+			if err := te.encodeSeparateMapping(w, subPath, v); err != nil {
 				return err
 			}
 		}

pkg/yqlib/json_test.go

@@ -220,6 +220,54 @@ var jsonScenarios = []formatScenario{
 		expected:       "{\"stuff\":\"cool\"}\n{\"whatever\":\"cat\"}\n",
 		scenarioType:   "encode",
 	},
+	{
+		description:    "Encode json: preserve floats with trailing zero",
+		subdescription: "Whole-number floats keep their decimal point so downstream consumers see a JSON number with a fractional part (matches Go's encoding/json, Python's json, and jq).",
+		input:          `percentiles: [50.0, 95.0, 99.0, 99.9]`,
+		indent:         0,
+		expected:       "{\"percentiles\":[50.0,95.0,99.0,99.9]}\n",
+		scenarioType:   "encode",
+	},
+	{
+		description:  "Encode json: ints stay ints",
+		skipDoc:      true,
+		input:        `a: 50`,
+		indent:       0,
+		expected:     "{\"a\":50}\n",
+		scenarioType: "encode",
+	},
+	{
+		description:  "Encode json: !!float tagged whole number gets .0",
+		skipDoc:      true,
+		input:        `a: !!float 5`,
+		indent:       0,
+		expected:     "{\"a\":5.0}\n",
+		scenarioType: "encode",
+	},
+	{
+		description:  "Encode json: scientific notation float preserved",
+		skipDoc:      true,
+		input:        `a: 1.5e-3`,
+		indent:       0,
+		expected:     "{\"a\":1.5e-3}\n",
+		scenarioType: "encode",
+	},
+	{
+		description:  "Encode json: negative float preserved",
+		skipDoc:      true,
+		input:        `a: -7.0`,
+		indent:       0,
+		expected:     "{\"a\":-7.0}\n",
+		scenarioType: "encode",
+	},
+	{
+		description:  "Encode json: mixed int and float array",
+		skipDoc:      true,
+		input:        `a: [1, 2.0, 3, 4.5]`,
+		indent:       0,
+		expected:     "{\"a\":[1,2.0,3,4.5]}\n",
+		scenarioType: "encode",
+	},
 	{
 		description:  "Roundtrip JSON Lines / NDJSON",
 		input:        sampleNdJson,

pkg/yqlib/lexer.go

@@ -131,6 +131,11 @@ func handleToken(tokens []*token, index int, postProcessedTokens []*token) (toke
 			log.Debugf("previous token is : traverseArrayOpType")
 			// need to put the number 0 before this token, as that is implied
 			postProcessedTokens = append(postProcessedTokens, &token{TokenType: operationToken, Operation: createValueOperation(0, "0")})
+		} else if index >= 2 && tokens[index-1].TokenType == openCollect &&
+			(tokens[index-2].TokenType == operationToken || tokens[index-2].TokenType == closeCollect || tokens[index-2].TokenType == closeCollectObject) {
+			log.Debugf("previous token is : openCollect following a traversal, implying 0 start")
+			// need to put the number 0 before this token, as that is implied
+			postProcessedTokens = append(postProcessedTokens, &token{TokenType: operationToken, Operation: createValueOperation(0, "0")})
 		}
 	}
 

pkg/yqlib/lexer_participle.go

@@ -96,6 +96,8 @@ var participleYqRules = []*participleYqRule{
 	simpleOp("load_?str|str_?load", loadStringOpType),
 	{"LoadYaml", `load`, loadOp(NewYamlDecoder(LoadYamlPreferences)), 0},
 
+	simpleOp("system", systemOpType),
+
 	{"SplitDocument", `splitDoc|split_?doc`, opToken(splitDocumentOpType), 0},
 
 	simpleOp("select", selectOpType),

pkg/yqlib/lib.go

@@ -80,7 +80,7 @@ func recurseNodeObjectEqual(lhs *CandidateNode, rhs *CandidateNode) bool {
 		key := lhs.Content[index]
 		value := lhs.Content[index+1]
 
-		indexInRHS := findInArray(rhs, key)
+		indexInRHS := findKeyInMap(rhs, key)
 
 		if indexInRHS == -1 || !recursiveNodeEqual(value, rhs.Content[indexInRHS+1]) {
 			return false

pkg/yqlib/lib_test.go

@@ -24,7 +24,7 @@ type parseSnippetScenario struct {
 var parseSnippetScenarios = []parseSnippetScenario{
 	{
 		snippet:       ":",
-		expectedError: "yaml: did not find expected key",
+		expectedError: "yaml: while parsing a block mapping at <unknown position>: did not find expected key",
 	},
 	{
 		snippet: "",
@@ -300,6 +300,24 @@ func TestRecurseNodeObjectEqual(t *testing.T) {
 	test.AssertResult(t, true, recurseNodeObjectEqual(obj1, obj2))
 	test.AssertResult(t, false, recurseNodeObjectEqual(obj1, obj3))
 	test.AssertResult(t, false, recurseNodeObjectEqual(obj1, obj4))
+
+	// A null key must not match a null value in the other map.
+	// Regression test for https://issues.oss-fuzz.com/issues/383860504
+	nullKey := &CandidateNode{Kind: ScalarNode, Tag: "!!null"}
+	nullVal := &CandidateNode{Kind: ScalarNode, Tag: "!!null"}
+	intKey := createScalarNode(2, "2")
+	intKey.Tag = "!!int"
+	intVal := &CandidateNode{Kind: ScalarNode, Tag: "!!null"}
+
+	mapWithNullKey := &CandidateNode{
+		Kind:    MappingNode,
+		Content: []*CandidateNode{nullKey, nullVal},
+	}
+	mapWithIntKey := &CandidateNode{
+		Kind:    MappingNode,
+		Content: []*CandidateNode{intKey, intVal},
+	}
+	test.AssertResult(t, false, recurseNodeObjectEqual(mapWithNullKey, mapWithIntKey))
 }
 
 func TestParseInt(t *testing.T) {

pkg/yqlib/operation.go

@@ -164,6 +164,8 @@ var stringInterpolationOpType = &operationType{Type: "STRING_INT", NumArgs: 0, P
 var loadOpType = &operationType{Type: "LOAD", NumArgs: 1, Precedence: 52, Handler: loadOperator, CheckForPostTraverse: true}
 var loadStringOpType = &operationType{Type: "LOAD_STRING", NumArgs: 1, Precedence: 52, Handler: loadStringOperator}
 
+var systemOpType = &operationType{Type: "SYSTEM", NumArgs: 1, Precedence: 50, Handler: systemOperator}
+
 var keysOpType = &operationType{Type: "KEYS", NumArgs: 0, Precedence: 52, Handler: keysOperator, CheckForPostTraverse: true}
 
 var collectObjectOpType = &operationType{Type: "COLLECT_OBJECT", NumArgs: 0, Precedence: 50, Handler: collectObjectOperator}

pkg/yqlib/operator_add_test.go

@@ -527,6 +527,18 @@ var addOperatorScenarios = []expressionScenario{
 		expression:    `.a += [2]`,
 		expectedError: "!!seq () cannot be added to a !!str (a)",
 	},
+	{
+		// Regression test for https://issues.oss-fuzz.com/issues/383860504
+		// Adding a map to itself must not panic when sequence keys contain
+		// single-entry mappings with a null key in one and a non-null key
+		// in the other.
+		skipDoc:    true,
+		document:   "? [{~: ~}]\n: v1\n? [{2: ~}]\n: v2",
+		expression: `. += .`,
+		expected: []string{
+			"D0, P[], (!!map)::? [{~: ~}]\n: v1\n? [{2: ~}]\n: v2\n",
+		},
+	},
 }
 
 func TestAddOperatorScenarios(t *testing.T) {

pkg/yqlib/operator_anchors_aliases.go

@@ -170,6 +170,10 @@ func fixedReconstructAliasedMap(node *CandidateNode) error {
 				if mergeNodeSeq.Kind == AliasNode {
 					mergeNodeSeq = mergeNodeSeq.Alias
 				}
+				mergeNodeSeq = mergeNodeSeq.Copy()
+				if err := explodeNode(mergeNodeSeq, Context{}); err != nil {
+					return err
+				}
 				if mergeNodeSeq.Kind != MappingNode {
 					return fmt.Errorf("can only use merge anchors with maps (!!map) or sequences (!!seq) of maps, but got sequence containing %v", mergeNodeSeq.Tag)
 				}
@@ -179,12 +183,7 @@ func fixedReconstructAliasedMap(node *CandidateNode) error {
 				})
 
 				for _, item := range itemsToAdd {
-					// copy to ensure exploding doesn't modify the original node
-					itemCopy := item.Copy()
-					if err := explodeNode(itemCopy, Context{}); err != nil {
-						return err
-					}
-					newContent = append(newContent, itemCopy)
+					newContent = append(newContent, item.Copy())
 				}
 			}
 		}

pkg/yqlib/operator_anchors_aliases_test.go

@@ -198,6 +198,15 @@ var fixedAnchorOperatorScenarios = []expressionScenario{
 			"D0, P[], (!!map)::{a: 42}\n",
 		},
 	},
+	{
+		skipDoc:     true,
+		description: "Nested merge anchor with inline map",
+		document:    `{<<: {<<: {a: 42}}}`,
+		expression:  `explode(.)`,
+		expected: []string{
+			"D0, P[], (!!map)::{a: 42}\n",
+		},
+	},
 	{
 		skipDoc:     true,
 		description: "Merge anchor with sequence with inline map",

pkg/yqlib/operator_contains.go

@@ -46,9 +46,9 @@ func containsObject(lhs *CandidateNode, rhs *CandidateNode) (bool, error) {
 		rhsKey := rhs.Content[index]
 		rhsValue := rhs.Content[index+1]
 		log.Debugf("Looking for %v in the lhs", rhsKey.Value)
-		lhsKeyIndex := findInArray(lhs, rhsKey)
+		lhsKeyIndex := findKeyInMap(lhs, rhsKey)
 		log.Debugf("index is %v", lhsKeyIndex)
-		if lhsKeyIndex < 0 || lhsKeyIndex%2 != 0 {
+		if lhsKeyIndex < 0 {
 			return false, nil
 		}
 		lhsValue := lhs.Content[lhsKeyIndex+1]

pkg/yqlib/operator_contains_test.go

@@ -65,6 +65,16 @@ var containsOperatorScenarios = []expressionScenario{
 			"D0, P[], (!!bool)::false\n",
 		},
 	},
+	{
+		// Regression: findInArray could match a null key against a null
+		// value at an earlier odd index, producing a false negative.
+		skipDoc:    true,
+		document:   "? 1\n: ~\n? ~\n: x",
+		expression: `contains({~: "x"})`,
+		expected: []string{
+			"D0, P[], (!!bool)::true\n",
+		},
+	},
 	{
 		description: "String contains substring",
 		document:    `"foobar"`,

pkg/yqlib/operator_multiply.go

@@ -155,8 +155,10 @@ func repeatString(lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error
 		return nil, err
 	} else if count < 0 {
 		return nil, fmt.Errorf("cannot repeat string by a negative number (%v)", count)
-	} else if count > 10000000 {
-		return nil, fmt.Errorf("cannot repeat string by more than 100 million (%v)", count)
+	}
+	maxResultLen := 10 * 1024 * 1024 // 10 MiB
+	if count > 0 && len(stringNode.Value) > maxResultLen/count {
+		return nil, fmt.Errorf("result of repeating string (%v bytes) by %v would exceed %v bytes", len(stringNode.Value), count, maxResultLen)
 	}
 	target.Value = strings.Repeat(stringNode.Value, count)
 

pkg/yqlib/operator_multiply_test.go

@@ -2,6 +2,7 @@ package yqlib
 
 import (
 	"fmt"
+	"math/bits"
 	"strings"
 	"testing"
 )
@@ -237,12 +238,11 @@ var multiplyOperatorScenarios = []expressionScenario{
 		expectedError: "cannot repeat string by a negative number (-4)",
 	},
 	{
-		description: "Multiply string X by more than 100 million",
-		// very large string.repeats causes a panic
+		description:   "Multiply string by count that exceeds result size limit",
 		skipDoc:       true,
 		document:      `n: 100000001`,
 		expression:    `"banana" * .n`,
-		expectedError: "cannot repeat string by more than 100 million (100000001)",
+		expectedError: "result of repeating string (6 bytes) by 100000001 would exceed 10485760 bytes",
 	},
 	{
 		description: "Multiply int node X string",
@@ -554,7 +554,7 @@ var multiplyOperatorScenarios = []expressionScenario{
 		document:   document,
 		expression: `.b * .c`,
 		expected: []string{
-			"D0, P[b], (!!map)::{name: dog, <<: *cat}\n",
+			"D0, P[b], (!!map)::{name: dog, \"<<\": *cat}\n",
 		},
 	},
 	{
@@ -693,6 +693,29 @@ var multiplyOperatorScenarios = []expressionScenario{
 			"D0, P[], (!!null)::null\n",
 		},
 	},
+	{
+		// Regression test for https://issues.oss-fuzz.com/issues/418818862
+		// Large repeat count with a long string must not panic.
+		skipDoc:       true,
+		expression:    `"abc" * 99999999`,
+		expectedError: "result of repeating string (3 bytes) by 99999999 would exceed 10485760 bytes",
+	},
+	{
+		// Regression test for https://issues.oss-fuzz.com/issues/383195001
+		// Product of string length * repeat count must be bounded.
+		skipDoc:       true,
+		expression:    `"x" * 99999999`,
+		expectedError: "result of repeating string (1 bytes) by 99999999 would exceed 10485760 bytes",
+	},
+	{
+		// Pick a count whose product with len("ab") overflows int on
+		// any architecture: 2^30 on 32-bit, 2^62 on 64-bit. Doubling
+		// either yields MaxInt+1, which wraps to MinInt and bypasses
+		// a naive len*count guard.
+		skipDoc:       true,
+		expression:    fmt.Sprintf(`"ab" * %d`, 1<<(bits.UintSize-2)),
+		expectedError: fmt.Sprintf("result of repeating string (2 bytes) by %d would exceed 10485760 bytes", 1<<(bits.UintSize-2)),
+	},
 }
 
 func TestMultiplyOperatorScenarios(t *testing.T) {

pkg/yqlib/operator_slice.go

@@ -16,6 +16,39 @@ func getSliceNumber(d *dataTreeNavigator, context Context, node *CandidateNode,
 	return parseInt(result.MatchingNodes.Front().Value.(*CandidateNode).Value)
 }
 
+// clampSliceIndex resolves a possibly-negative slice index against
+// length and clamps the result to [0, length].
+func clampSliceIndex(index, length int) int {
+	if index < 0 {
+		index += length
+	}
+	if index < 0 {
+		return 0
+	}
+	if index > length {
+		return length
+	}
+	return index
+}
+
+func sliceStringNode(lhsNode *CandidateNode, firstNumber int, secondNumber int) *CandidateNode {
+	runes := []rune(lhsNode.Value)
+	length := len(runes)
+
+	relativeFirstNumber := clampSliceIndex(firstNumber, length)
+	relativeSecondNumber := clampSliceIndex(secondNumber, length)
+	if relativeSecondNumber < relativeFirstNumber {
+		relativeSecondNumber = relativeFirstNumber
+	}
+
+	log.Debugf("sliceStringNode: slice from %v to %v", relativeFirstNumber, relativeSecondNumber)
+
+	slicedString := string(runes[relativeFirstNumber:relativeSecondNumber])
+	replacement := lhsNode.CreateReplacement(ScalarNode, lhsNode.Tag, slicedString)
+	replacement.Style = lhsNode.Style
+	return replacement
+}
+
 func sliceArrayOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
 
 	log.Debug("slice array operator!")
@@ -28,27 +61,23 @@ func sliceArrayOperator(d *dataTreeNavigator, context Context, expressionNode *E
 		lhsNode := el.Value.(*CandidateNode)
 
 		firstNumber, err := getSliceNumber(d, context, lhsNode, expressionNode.LHS)
-
 		if err != nil {
 			return Context{}, err
 		}
-		relativeFirstNumber := firstNumber
-		if relativeFirstNumber < 0 {
-			relativeFirstNumber = len(lhsNode.Content) + firstNumber
-		}
 
 		secondNumber, err := getSliceNumber(d, context, lhsNode, expressionNode.RHS)
 		if err != nil {
 			return Context{}, err
 		}
 
-		relativeSecondNumber := secondNumber
-		if relativeSecondNumber < 0 {
-			relativeSecondNumber = len(lhsNode.Content) + secondNumber
-		} else if relativeSecondNumber > len(lhsNode.Content) {
-			relativeSecondNumber = len(lhsNode.Content)
+		if lhsNode.Kind == ScalarNode && lhsNode.guessTagFromCustomType() == "!!str" {
+			results.PushBack(sliceStringNode(lhsNode, firstNumber, secondNumber))
+			continue
 		}
 
+		relativeFirstNumber := clampSliceIndex(firstNumber, len(lhsNode.Content))
+		relativeSecondNumber := clampSliceIndex(secondNumber, len(lhsNode.Content))
+
 		log.Debugf("calculateIndicesToTraverse: slice from %v to %v", relativeFirstNumber, relativeSecondNumber)
 
 		var newResults []*CandidateNode

pkg/yqlib/operator_slice_test.go

@@ -98,6 +98,115 @@ var sliceArrayScenarios = []expressionScenario{
 			"D0, P[], (!!seq)::- cat1\n",
 		},
 	},
+	{
+		// Regression test for https://issues.oss-fuzz.com/issues/438776028
+		// Negative second index that underflows after adjustment must
+		// clamp to zero, yielding an empty sequence.
+		skipDoc:    true,
+		document:   `[a, b, c]`,
+		expression: `.[0:-99999]`,
+		expected: []string{
+			"D0, P[], (!!seq)::[]\n",
+		},
+	},
+	{
+		// First-index underflow: without clamping, the loop starts at a
+		// negative index and panics on Content access.
+		skipDoc:    true,
+		document:   `[a, b, c]`,
+		expression: `.[-99999:3]`,
+		expected: []string{
+			"D0, P[], (!!seq)::- a\n- b\n- c\n",
+		},
+	},
+	{
+		// Both indices underflow: both clamp to zero, yielding an empty
+		// sequence.
+		skipDoc:    true,
+		document:   `[a, b, c]`,
+		expression: `.[-99999:-99998]`,
+		expected: []string{
+			"D0, P[], (!!seq)::[]\n",
+		},
+	},
+	{
+		description: "Slicing strings",
+		document:    `country: Australia`,
+		expression:  `.country[0:5]`,
+		expected: []string{
+			"D0, P[country], (!!str)::Austr\n",
+		},
+	},
+	{
+		description:    "Slicing strings - without the second number",
+		subdescription: "Finishes at the end of the string",
+		document:       `country: Australia`,
+		expression:     `.country[5:]`,
+		expected: []string{
+			"D0, P[country], (!!str)::alia\n",
+		},
+	},
+	{
+		description:    "Slicing strings - without the first number",
+		subdescription: "Starts from the start of the string",
+		document:       `country: Australia`,
+		expression:     `.country[:5]`,
+		expected: []string{
+			"D0, P[country], (!!str)::Austr\n",
+		},
+	},
+	{
+		description:    "Slicing strings - use negative numbers to count backwards from the end",
+		subdescription: "Negative indices count from the end of the string",
+		document:       `country: Australia`,
+		expression:     `.country[-5:]`,
+		expected: []string{
+			"D0, P[country], (!!str)::ralia\n",
+		},
+	},
+	{
+		skipDoc:    true,
+		document:   `country: Australia`,
+		expression: `.country[1:-1]`,
+		expected: []string{
+			"D0, P[country], (!!str)::ustrali\n",
+		},
+	},
+	{
+		skipDoc:    true,
+		document:   `country: Australia`,
+		expression: `.country[:]`,
+		expected: []string{
+			"D0, P[country], (!!str)::Australia\n",
+		},
+	},
+	{
+		skipDoc:     true,
+		description: "second index beyond string length clamps",
+		document:    `country: Australia`,
+		expression:  `.country[:100]`,
+		expected: []string{
+			"D0, P[country], (!!str)::Australia\n",
+		},
+	},
+	{
+		skipDoc:     true,
+		description: "first index beyond string length returns empty string",
+		document:    `country: Australia`,
+		expression:  `.country[100:]`,
+		expected: []string{
+			"D0, P[country], (!!str)::\n",
+		},
+	},
+	{
+		description:    "Slicing strings - Unicode",
+		subdescription: "Indices are rune-based, so multi-byte characters are handled correctly",
+		document:       `greeting: héllo`,
+		expression:     `.greeting[1:3]`,
+		expected: []string{
+			"D0, P[greeting], (!!str)::él\n",
+		},
+	},
 }
 
 func TestSliceOperatorScenarios(t *testing.T) {

pkg/yqlib/operator_system.go

@@ -0,0 +1,146 @@
+package yqlib
+
+import (
+	"bytes"
+	"container/list"
+	"fmt"
+	"os/exec"
+	"strings"
+)
+
+func resolveSystemArgs(argsNode *CandidateNode) ([]string, error) {
+	if argsNode == nil {
+		return nil, nil
+	}
+
+	if argsNode.Kind == SequenceNode {
+		args := make([]string, 0, len(argsNode.Content))
+		for _, child := range argsNode.Content {
+			// Only non-null scalar children are valid arguments.
+			if child == nil {
+				continue
+			}
+			if child.Kind != ScalarNode || child.Tag == "!!null" {
+				return nil, fmt.Errorf("system operator: argument must be a non-null scalar; got kind=%v tag=%v", child.Kind, child.Tag)
+			}
+			args = append(args, child.Value)
+		}
+		if len(args) == 0 {
+			return nil, nil
+		}
+		return args, nil
+	}
+
+	// Single-argument case: only accept a non-null scalar node.
+	if argsNode.Tag == "!!null" {
+		return nil, nil
+	}
+	if argsNode.Kind != ScalarNode {
+		return nil, fmt.Errorf("system operator: args must be a non-null scalar or sequence of non-null scalars; got kind=%v tag=%v", argsNode.Kind, argsNode.Tag)
+	}
+	return []string{argsNode.Value}, nil
+}
+
+func resolveCommandNode(commandNodes Context) (string, error) {
+	if commandNodes.MatchingNodes.Front() == nil {
+		return "", fmt.Errorf("system operator: command expression returned no results")
+	}
+	if commandNodes.MatchingNodes.Len() > 1 {
+		log.Debugf("system operator: command expression returned %d results, using first", commandNodes.MatchingNodes.Len())
+	}
+	cmdNode := commandNodes.MatchingNodes.Front().Value.(*CandidateNode)
+	if cmdNode.Kind != ScalarNode || cmdNode.guessTagFromCustomType() != "!!str" {
+		return "", fmt.Errorf("system operator: command must be a string scalar")
+	}
+	if cmdNode.Value == "" {
+		return "", fmt.Errorf("system operator: command must be a non-empty string")
+	}
+	return cmdNode.Value, nil
+}
+
+func systemOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
+	if !ConfiguredSecurityPreferences.EnableSystemOps {
+		return Context{}, fmt.Errorf("system operations are disabled, use --security-enable-system-operator to enable")
+	}
+
+	// determine at parse time whether we have (command; args) or just (command)
+	hasArgs := expressionNode.RHS.Operation.OperationType == blockOpType
+
+	var results = list.New()
+
+	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+		candidate := el.Value.(*CandidateNode)
+		nodeContext := context.SingleReadonlyChildContext(candidate)
+
+		var command string
+		var args []string
+
+		if hasArgs {
+			block := expressionNode.RHS
+			commandNodes, err := d.GetMatchingNodes(nodeContext, block.LHS)
+			if err != nil {
+				return Context{}, err
+			}
+			command, err = resolveCommandNode(commandNodes)
+			if err != nil {
+				return Context{}, err
+			}
+
+			argsNodes, err := d.GetMatchingNodes(nodeContext, block.RHS)
+			if err != nil {
+				return Context{}, err
+			}
+			if argsNodes.MatchingNodes.Len() > 1 {
+				log.Debugf("system operator: args expression returned %d results, using first", argsNodes.MatchingNodes.Len())
+			}
+			if argsNodes.MatchingNodes.Front() != nil {
+				args, err = resolveSystemArgs(argsNodes.MatchingNodes.Front().Value.(*CandidateNode))
+				if err != nil {
+					return Context{}, err
+				}
+			}
+		} else {
+			commandNodes, err := d.GetMatchingNodes(nodeContext, expressionNode.RHS)
+			if err != nil {
+				return Context{}, err
+			}
+			command, err = resolveCommandNode(commandNodes)
+			if err != nil {
+				return Context{}, err
+			}
+		}
+
+		var stdin bytes.Buffer
+		encoded, err := encodeToYamlString(candidate)
+		if err != nil {
+			return Context{}, err
+		}
+		stdin.WriteString(encoded)
+
+		// #nosec G204 - intentional: user must explicitly enable this operator
+		cmd := exec.Command(command, args...)
+		cmd.Stdin = &stdin
+		var stderr bytes.Buffer
+		cmd.Stderr = &stderr
+
+		output, err := cmd.Output()
+		if err != nil {
+			stderrStr := strings.TrimSpace(stderr.String())
+			if stderrStr != "" {
+				return Context{}, fmt.Errorf("system command '%v' failed: %w\nstderr: %v", command, err, stderrStr)
+			}
+			return Context{}, fmt.Errorf("system command '%v' failed: %w", command, err)
+		}
+
+		result := string(output)
+		if strings.HasSuffix(result, "\r\n") {
+			result = result[:len(result)-2]
+		} else if strings.HasSuffix(result, "\n") {
+			result = result[:len(result)-1]
+		}
+		newNode := candidate.CreateReplacement(ScalarNode, "!!str", result)
+		results.PushBack(newNode)
+	}
+
+	return context.ChildContext(results), nil
+}

pkg/yqlib/operator_system_test.go

@@ -0,0 +1,123 @@
+package yqlib
+
+import (
+	"os/exec"
+	"testing"
+)
+
+func findExec(t *testing.T, name string) string {
+	t.Helper()
+	path, err := exec.LookPath(name)
+	if err != nil {
+		t.Skipf("skipping: %v not found: %v", name, err)
+	}
+	return path
+}
+
+var systemOperatorDisabledScenarios = []expressionScenario{
+	{
+		description:    "system operator returns error when disabled",
+		subdescription: "Use `--security-enable-system-operator` to enable the system operator.",
+		document:       "country: Australia",
+		expression:     `.country = system("/usr/bin/echo"; "test")`,
+		expectedError:  "system operations are disabled, use --security-enable-system-operator to enable",
+	},
+}
+
+func TestSystemOperatorDisabledScenarios(t *testing.T) {
+	originalEnableSystemOps := ConfiguredSecurityPreferences.EnableSystemOps
+	defer func() {
+		ConfiguredSecurityPreferences.EnableSystemOps = originalEnableSystemOps
+	}()
+
+	ConfiguredSecurityPreferences.EnableSystemOps = false
+
+	for _, tt := range systemOperatorDisabledScenarios {
+		testScenario(t, &tt)
+	}
+	documentOperatorScenarios(t, "system-operators", systemOperatorDisabledScenarios)
+}
+
+func TestSystemOperatorEnabledScenarios(t *testing.T) {
+	echoPath := findExec(t, "echo")
+	falsePath := findExec(t, "false")
+
+	originalEnableSystemOps := ConfiguredSecurityPreferences.EnableSystemOps
+	defer func() {
+		ConfiguredSecurityPreferences.EnableSystemOps = originalEnableSystemOps
+	}()
+
+	ConfiguredSecurityPreferences.EnableSystemOps = true
+
+	scenarios := []expressionScenario{
+		{
+			description:    "Run a command with an argument",
+			subdescription: "Use `--security-enable-system-operator` to enable the system operator.",
+			yqFlags:        "--security-enable-system-operator",
+			document:       "country: Australia",
+			expression:     `.country = system("` + echoPath + `"; "test")`,
+			expected: []string{
+				"D0, P[], (!!map)::country: test\n",
+			},
+		},
+		{
+			description:    "Run a command without arguments",
+			subdescription: "Omit the semicolon and args to run the command with no extra arguments.",
+			yqFlags:        "--security-enable-system-operator",
+			document:       "a: hello",
+			expression:     `.a = system("` + echoPath + `")`,
+			expected: []string{
+				"D0, P[], (!!map)::a: \"\"\n",
+			},
+		},
+		{
+			description:    "Run a command with multiple arguments",
+			subdescription: "Pass an array of arguments.",
+			skipDoc:        true,
+			document:       "a: hello",
+			expression:     `.a = system("` + echoPath + `"; ["foo", "bar"])`,
+			expected: []string{
+				"D0, P[], (!!map)::a: foo bar\n",
+			},
+		},
+		{
+			description: "Command and args are evaluated per matched node",
+			skipDoc:     true,
+			document:    "cmd: " + echoPath + "\narg: hello",
+			expression:  `.result = system(.cmd; .arg)`,
+			expected: []string{
+				"D0, P[], (!!map)::cmd: " + echoPath + "\narg: hello\nresult: hello\n",
+			},
+		},
+		{
+			description:   "Command failure returns error",
+			skipDoc:       true,
+			document:      "a: hello",
+			expression:    `.a = system("` + falsePath + `")`,
+			expectedError: "system command '" + falsePath + "' failed: exit status 1",
+		},
+		{
+			description:   "Null command returns error",
+			skipDoc:       true,
+			document:      "a: hello",
+			expression:    `.a = system(null)`,
+			expectedError: "system operator: command must be a string scalar",
+		},
+		{
+			description: "System operator processes multiple matched nodes",
+			skipDoc:     true,
+			document:    "a: first",
+			document2:   "a: second",
+			expression:  `.a = system("` + echoPath + `"; "replaced")`,
+			expected: []string{
+				"D0, P[], (!!map)::a: replaced\n",
+				"D0, P[], (!!map)::a: replaced\n",
+			},
+		},
+	}
+
+	for _, tt := range scenarios {
+		testScenario(t, &tt)
+	}
+	appendOperatorDocumentScenario(t, "system-operators", scenarios)
+}

pkg/yqlib/operator_traverse_path.go

@@ -36,9 +36,33 @@ func traversePathOperator(_ *dataTreeNavigator, context Context, expressionNode
 	return context.ChildContext(matches), nil
 }
 
+// resolveAliasChain follows an alias chain iteratively, returning the
+// first non-alias node. Returns an error if a cycle is detected.
+func resolveAliasChain(node *CandidateNode) (*CandidateNode, error) {
+	if node.Kind != AliasNode {
+		return node, nil
+	}
+	visited := map[*CandidateNode]bool{}
+	for node.Kind == AliasNode {
+		if visited[node] {
+			return nil, fmt.Errorf("alias cycle detected")
+		}
+		visited[node] = true
+		log.Debug("its an alias!")
+		node = node.Alias
+	}
+	return node, nil
+}
+
 func traverse(context Context, matchingNode *CandidateNode, operation *Operation) (*list.List, error) {
 	log.Debugf("Traversing %v", NodeToString(matchingNode))
 
+	var err error
+	matchingNode, err = resolveAliasChain(matchingNode)
+	if err != nil {
+		return nil, err
+	}
+
 	if matchingNode.Tag == "!!null" && operation.Value != "[]" && !context.DontAutoCreate {
 		log.Debugf("Guessing kind")
 		// we must have added this automatically, lets guess what it should be now
@@ -62,10 +86,6 @@ func traverse(context Context, matchingNode *CandidateNode, operation *Operation
 		log.Debugf("its a sequence of %v things!", len(matchingNode.Content))
 		return traverseArray(matchingNode, operation, operation.Preferences.(traversePreferences))
 
-	case AliasNode:
-		log.Debug("its an alias!")
-		matchingNode = matchingNode.Alias
-		return traverse(context, matchingNode, operation)
 	default:
 		return list.New(), nil
 	}
@@ -79,7 +99,11 @@ func traverseArrayOperator(d *dataTreeNavigator, context Context, expressionNode
 	log.Debugf("--traverseArrayOperator")
 
 	if expressionNode.RHS != nil && expressionNode.RHS.RHS != nil && expressionNode.RHS.RHS.Operation.OperationType == createMapOpType {
-		return sliceArrayOperator(d, context, expressionNode.RHS.RHS)
+		lhsContext, err := d.GetMatchingNodes(context, expressionNode.LHS)
+		if err != nil {
+			return Context{}, err
+		}
+		return sliceArrayOperator(d, lhsContext, expressionNode.RHS.RHS)
 	}
 
 	lhs, err := d.GetMatchingNodes(context, expressionNode.LHS)
@@ -125,7 +149,13 @@ func traverseNodesWithArrayIndices(context Context, indicesToTraverse []*Candida
 	return context.ChildContext(matchingNodeMap), nil
 }
 
-func traverseArrayIndices(context Context, matchingNode *CandidateNode, indicesToTraverse []*CandidateNode, prefs traversePreferences) (*list.List, error) { // call this if doc / alias like the other traverse
+func traverseArrayIndices(context Context, matchingNode *CandidateNode, indicesToTraverse []*CandidateNode, prefs traversePreferences) (*list.List, error) {
+	var err error
+	matchingNode, err = resolveAliasChain(matchingNode)
+	if err != nil {
+		return nil, err
+	}
+
 	if matchingNode.Tag == "!!null" {
 		log.Debugf("OperatorArrayTraverse got a null - turning it into an empty array")
 		// auto vivification
@@ -138,9 +168,6 @@ func traverseArrayIndices(context Context, matchingNode *CandidateNode, indicesT
 	}
 
 	switch matchingNode.Kind {
-	case AliasNode:
-		matchingNode = matchingNode.Alias
-		return traverseArrayIndices(context, matchingNode, indicesToTraverse, prefs)
 	case SequenceNode:
 		return traverseArrayWithIndices(matchingNode, indicesToTraverse, prefs)
 	case MappingNode:

pkg/yqlib/operator_traverse_path_test.go

@@ -665,6 +665,16 @@ var traversePathOperatorScenarios = []expressionScenario{
 			"D0, P[a], (!!null)::null\n",
 		},
 	},
+	{
+		// Regression test for https://issues.oss-fuzz.com/issues/390467412
+		// go-yaml accepts cross-document alias references (invalid per
+		// YAML spec). A nested assignment on such an alias can create a
+		// circular alias node, which must not cause a stack overflow.
+		skipDoc:       true,
+		document:      "&-- a\n---\n*--",
+		expression:    ". = (.x = 1)",
+		expectedError: "alias cycle detected",
+	},
 }
 
 func TestTraversePathOperatorScenarios(t *testing.T) {
@@ -682,3 +692,58 @@ func TestTraversePathOperatorAlignedToSpecScenarios(t *testing.T) {
 	appendOperatorDocumentScenario(t, "traverse-read", fixedTraversePathOperatorScenarios)
 	ConfiguredYamlPreferences.FixMergeAnchorToSpec = false
 }
+
+// Regression test for https://issues.oss-fuzz.com/issues/390467412
+// A circular alias (alias pointing back to itself) must not cause a
+// stack overflow. resolveAliasChain should detect the cycle and return
+// an error; both traverse() and traverseArrayIndices() use it.
+func TestTraverseAliasCycle(t *testing.T) {
+	aliasNode := &CandidateNode{
+		Kind: AliasNode,
+	}
+	aliasNode.Alias = aliasNode // A -> A
+
+	op := &Operation{
+		OperationType: traversePathOpType,
+		Value:         "key",
+		StringValue:   "key",
+		Preferences:   traversePreferences{},
+	}
+	_, err := traverse(Context{}, aliasNode, op)
+	if err == nil {
+		t.Fatal("expected error for alias cycle, got nil")
+	}
+	if err.Error() != "alias cycle detected" {
+		t.Fatalf("expected 'alias cycle detected', got %q", err.Error())
+	}
+
+	// Same cycle must be caught through the array traversal path.
+	_, err = traverseArrayIndices(Context{}, aliasNode, nil, traversePreferences{})
+	if err == nil {
+		t.Fatal("expected error for alias cycle via traverseArrayIndices, got nil")
+	}
+	if err.Error() != "alias cycle detected" {
+		t.Fatalf("expected 'alias cycle detected', got %q", err.Error())
+	}
+}
+
+func TestTraverseAliasCycleChain(t *testing.T) {
+	nodeA := &CandidateNode{Kind: AliasNode}
+	nodeB := &CandidateNode{Kind: AliasNode}
+	nodeA.Alias = nodeB
+	nodeB.Alias = nodeA // A -> B -> A
+
+	op := &Operation{
+		OperationType: traversePathOpType,
+		Value:         "key",
+		StringValue:   "key",
+		Preferences:   traversePreferences{},
+	}
+	_, err := traverse(Context{}, nodeA, op)
+	if err == nil {
+		t.Fatal("expected error for alias cycle chain, got nil")
+	}
+	if err.Error() != "alias cycle detected" {
+		t.Fatalf("expected 'alias cycle detected', got %q", err.Error())
+	}
+}

pkg/yqlib/operators_test.go

@@ -31,6 +31,7 @@ type expressionScenario struct {
 	dontFormatInputForDoc bool // dont format input doc for documentation generation
 	requiresFormat        string
 	skipForGoccy          bool
+	yqFlags               string // extra yq flags to include in generated doc command snippets
 }
 
 var goccyTesting = false
@@ -356,14 +357,22 @@ func documentInput(w *bufio.Writer, s expressionScenario) (string, string) {
 
 		writeOrPanic(w, "then\n")
 
+		flagsPrefix := ""
+		if s.yqFlags != "" {
+			flagsPrefix = s.yqFlags + " "
+		}
 		if s.expression != "" {
-			writeOrPanic(w, fmt.Sprintf("```bash\n%vyq %v'%v' %v\n```\n", envCommand, command, strings.ReplaceAll(s.expression, "'", `'\''`), files))
+			writeOrPanic(w, fmt.Sprintf("```bash\n%vyq %v%v'%v' %v\n```\n", envCommand, flagsPrefix, command, strings.ReplaceAll(s.expression, "'", `'\''`), files))
 		} else {
-			writeOrPanic(w, fmt.Sprintf("```bash\n%vyq %v%v\n```\n", envCommand, command, files))
+			writeOrPanic(w, fmt.Sprintf("```bash\n%vyq %v%v%v\n```\n", envCommand, flagsPrefix, command, files))
 		}
 	} else {
 		writeOrPanic(w, "Running\n")
-		writeOrPanic(w, fmt.Sprintf("```bash\n%vyq %v--null-input '%v'\n```\n", envCommand, command, s.expression))
+		flagsPrefix := ""
+		if s.yqFlags != "" {
+			flagsPrefix = s.yqFlags + " "
+		}
+		writeOrPanic(w, fmt.Sprintf("```bash\n%vyq %v%v--null-input '%v'\n```\n", envCommand, flagsPrefix, command, s.expression))
 	}
 	return formattedDoc, formattedDoc2
 }

pkg/yqlib/properties_test.go

@@ -202,6 +202,37 @@ var propertyScenarios = []formatScenario{
 		expected:     expectedDecodedYaml,
 		scenarioType: "decode",
 	},
+	{
+		skipDoc:     true,
+		description: "Decode properties with array brackets",
+		input: `user.credentials[0].username=user1
+user.credentials[0].password=$2b$08$...
+user.credentials[1].username=user2
+user.credentials[1].password=$2b$08$...
+user.credentials[2].username=user3
+user.credentials[2].password=$2b$10$...`,
+		expected: `user:
+  credentials:
+    - username: user1
+      password: $2b$08$...
+    - username: user2
+      password: $2b$08$...
+    - username: user3
+      password: $2b$10$...
+`,
+		scenarioType: "decode-array-brackets",
+	},
+	{
+		skipDoc:     true,
+		description: "Decode properties with nested array brackets",
+		input:       `user.clowns[0][1] = "cool"`,
+		expected: `user:
+  clowns:
+    - - null
+      - '"cool"'
+`,
+		scenarioType: "decode-array-brackets",
+	},
 
 	{
 		skipDoc:      true,
@@ -442,6 +473,12 @@ func TestPropertyScenarios(t *testing.T) {
 			test.AssertResultWithContext(t, s.expected, mustProcessFormatScenario(s, NewYamlDecoder(ConfiguredYamlPreferences), NewPropertiesEncoder(ConfiguredPropertiesPreferences)), s.description)
 		case "decode":
 			test.AssertResultWithContext(t, s.expected, mustProcessFormatScenario(s, NewPropertiesDecoder(), NewYamlEncoder(ConfiguredYamlPreferences)), s.description)
+		case "decode-array-brackets":
+			previousPreferences := ConfiguredPropertiesPreferences.Copy()
+			ConfiguredPropertiesPreferences.UseArrayBrackets = true
+			actual := mustProcessFormatScenario(s, NewPropertiesDecoder(), NewYamlEncoder(ConfiguredYamlPreferences))
+			ConfiguredPropertiesPreferences = previousPreferences
+			test.AssertResultWithContext(t, s.expected, actual, s.description)
 		case "encode-wrapped":
 			prefs := ConfiguredPropertiesPreferences.Copy()
 			prefs.UnwrapScalar = false

pkg/yqlib/security_prefs.go

@@ -1,11 +1,13 @@
 package yqlib
 
 type SecurityPreferences struct {
-	DisableEnvOps  bool
-	DisableFileOps bool
+	DisableEnvOps   bool
+	DisableFileOps  bool
+	EnableSystemOps bool
 }
 
 var ConfiguredSecurityPreferences = SecurityPreferences{
-	DisableEnvOps:  false,
-	DisableFileOps: false,
+	DisableEnvOps:   false,
+	DisableFileOps:  false,
+	EnableSystemOps: false,
 }

pkg/yqlib/toml_test.go

@@ -209,6 +209,50 @@ address = "12 cat st"
 var rtEmptyArray = `A = []
 `
 
+var rtEmptyArrayInTable = `[features]
+my-feature = []
+`
+
+var rtMixedEmptyArraysInTable = `[features]
+my-other-feature = []
+my-feature = ["my-other-feature"]
+`
+
+var yamlEmptyArrayInTable = `features:
+  my-feature: []
+`
+
+var expectedTomlEmptyArrayInTable = `[features]
+my-feature = []
+`
+
+var yamlMixedEmptyArraysInTable = `features:
+  my-other-feature: []
+  my-feature:
+    - my-other-feature
+`
+
+var expectedTomlMixedEmptyArraysInTable = `[features]
+my-other-feature = []
+my-feature = ["my-other-feature"]
+`
+
+var issue2688SampleToml = `[project]
+name = "some-project"
+version = "0.5.1"
+authors = [{name = "Author", email = "author@example.com"}]
+license = { file = "LICENSE" }
+readme = "README.md"
+`
+
+var issue2688SampleExpected = `[project]
+name = "some-project"
+version = "0.5.2"
+authors = [{ name = "Author", email = "author@example.com" }]
+license = { file = "LICENSE" }
+readme = "README.md"
+`
+
 var rtSampleTable = `var = "x"
 
 [owner.contact]
@@ -287,6 +331,18 @@ var expectedSubArrays = `array:
           - {}
 `
 
+// Keys with special characters that require quoting in TOML
+var rtSpecialKeyInlineTable = `host = { "http://sealos.hub:5000" = { capabilities = ["pull", "resolve", "push"], skip_verify = true } }
+`
+
+var rtSpecialKeyTableSection = `["/tmp/blah"]
+value = "hello"
+`
+
+var rtSpecialKeyDottedTableSection = `[servers."http://localhost:8080"]
+ip = "127.0.0.1"
+`
+
 var tomlScenarios = []formatScenario{
 	{
 		skipDoc:      true,
@@ -551,6 +607,36 @@ var tomlScenarios = []formatScenario{
 		expected:     rtEmptyArray,
 		scenarioType: "roundtrip",
 	},
+	{
+		skipDoc:      true,
+		description:  "Issue #2674: roundtrip empty array in table",
+		input:        rtEmptyArrayInTable,
+		expression:   ".",
+		expected:     rtEmptyArrayInTable,
+		scenarioType: "roundtrip",
+	},
+	{
+		skipDoc:      true,
+		description:  "Issue #2674: roundtrip mixed empty and non-empty arrays in table",
+		input:        rtMixedEmptyArraysInTable,
+		expression:   ".",
+		expected:     rtMixedEmptyArraysInTable,
+		scenarioType: "roundtrip",
+	},
+	{
+		skipDoc:      true,
+		description:  "Issue #2674: encode empty array in table",
+		input:        yamlEmptyArrayInTable,
+		expected:     expectedTomlEmptyArrayInTable,
+		scenarioType: "encode",
+	},
+	{
+		skipDoc:      true,
+		description:  "Issue #2674: encode mixed empty and non-empty arrays in table",
+		input:        yamlMixedEmptyArraysInTable,
+		expected:     expectedTomlMixedEmptyArraysInTable,
+		scenarioType: "encode",
+	},
 	{
 		description:  "Roundtrip: sample table",
 		input:        rtSampleTable,
@@ -614,6 +700,80 @@ var tomlScenarios = []formatScenario{
 		expected:     tomlTableWithComments,
 		scenarioType: "roundtrip",
 	},
+	// Encode (YAML → TOML) scenarios - verify readable table sections are produced
+	{
+		description:  "Encode: Simple mapping produces table section",
+		input:        "arg:\n  hello: foo\n",
+		expected:     "[arg]\nhello = \"foo\"\n",
+		scenarioType: "encode",
+	},
+	{
+		skipDoc:      true,
+		description:  "Encode: Nested mappings produce nested table sections",
+		input:        "a:\n  b:\n    c: val\n",
+		expected:     "[a.b]\nc = \"val\"\n",
+		scenarioType: "encode",
+	},
+	{
+		skipDoc:      true,
+		description:  "Encode: Mixed scalars and nested mapping",
+		input:        "a:\n  hello: foo\n  nested:\n    key: val\n",
+		expected:     "[a]\nhello = \"foo\"\n\n[a.nested]\nkey = \"val\"\n",
+		scenarioType: "encode",
+	},
+	{
+		skipDoc:      true,
+		description:  "Encode: YAML flow mapping produces table section (same as block mapping)",
+		input:        "arg: {hello: foo}\n",
+		expected:     "[arg]\nhello = \"foo\"\n",
+		scenarioType: "encode",
+	},
+	{
+		skipDoc:      true,
+		description:  "Issue: JSON auto-detected via YAML decoder produces table sections",
+		input:        `{"arg":{"hello": "foo"}}`,
+		expected:     "[arg]\nhello = \"foo\"\n",
+		scenarioType: "encode",
+	},
+	{
+		skipDoc:      true,
+		description:  "Issue: JSON via JSON decoder produces table sections",
+		input:        `{"arg":{"hello": "foo"}}`,
+		expected:     "[arg]\nhello = \"foo\"\n",
+		scenarioType: "encode-json",
+	},
+	{
+		skipDoc:      true,
+		description:  "Issue 2688: inline table arrays do not change following table scope",
+		input:        issue2688SampleToml,
+		expression:   `.project.version = "0.5.2"`,
+		expected:     issue2688SampleExpected,
+		scenarioType: "roundtrip",
+	},
+	{
+		skipDoc:      true,
+		description:  "Roundtrip: key with special characters in inline table",
+		input:        rtSpecialKeyInlineTable,
+		expression:   ".",
+		expected:     rtSpecialKeyInlineTable,
+		scenarioType: "roundtrip",
+	},
+	{
+		skipDoc:      true,
+		description:  "Roundtrip: key with special characters in table section",
+		input:        rtSpecialKeyTableSection,
+		expression:   ".",
+		expected:     rtSpecialKeyTableSection,
+		scenarioType: "roundtrip",
+	},
+	{
+		skipDoc:      true,
+		description:  "Roundtrip: special character key in dotted table section header",
+		input:        rtSpecialKeyDottedTableSection,
+		expression:   ".",
+		expected:     rtSpecialKeyDottedTableSection,
+		scenarioType: "roundtrip",
+	},
 }
 
 func testTomlScenario(t *testing.T, s formatScenario) {
@@ -629,6 +789,10 @@ func testTomlScenario(t *testing.T, s formatScenario) {
 		}
 	case "roundtrip":
 		test.AssertResultWithContext(t, s.expected, mustProcessFormatScenario(s, NewTomlDecoder(), NewTomlEncoder()), s.description)
+	case "encode":
+		test.AssertResultWithContext(t, s.expected, mustProcessFormatScenario(s, NewYamlDecoder(ConfiguredYamlPreferences), NewTomlEncoder()), s.description)
+	case "encode-json":
+		test.AssertResultWithContext(t, s.expected, mustProcessFormatScenario(s, NewJSONDecoder(), NewTomlEncoder()), s.description)
 	}
 }
 
@@ -654,6 +818,28 @@ func documentTomlDecodeScenario(w *bufio.Writer, s formatScenario) {
 	writeOrPanic(w, fmt.Sprintf("```yaml\n%v```\n\n", mustProcessFormatScenario(s, NewTomlDecoder(), NewYamlEncoder(ConfiguredYamlPreferences))))
 }
 
+func documentTomlEncodeScenario(w *bufio.Writer, s formatScenario) {
+	writeOrPanic(w, fmt.Sprintf("## %v\n", s.description))
+
+	if s.subdescription != "" {
+		writeOrPanic(w, s.subdescription)
+		writeOrPanic(w, "\n\n")
+	}
+
+	writeOrPanic(w, "Given a sample.yml file of:\n")
+	writeOrPanic(w, fmt.Sprintf("```yaml\n%v\n```\n", s.input))
+
+	writeOrPanic(w, "then\n")
+	expression := s.expression
+	if expression == "" {
+		expression = "."
+	}
+	writeOrPanic(w, fmt.Sprintf("```bash\nyq -o toml '%v' sample.yml\n```\n", expression))
+	writeOrPanic(w, "will output\n")
+
+	writeOrPanic(w, fmt.Sprintf("```toml\n%v```\n\n", mustProcessFormatScenario(s, NewYamlDecoder(ConfiguredYamlPreferences), NewTomlEncoder())))
+}
+
 func documentTomlRoundtripScenario(w *bufio.Writer, s formatScenario) {
 	writeOrPanic(w, fmt.Sprintf("## %v\n", s.description))
 
@@ -687,6 +873,8 @@ func documentTomlScenario(_ *testing.T, w *bufio.Writer, i interface{}) {
 		documentTomlDecodeScenario(w, s)
 	case "roundtrip":
 		documentTomlRoundtripScenario(w, s)
+	case "encode", "encode-json":
+		documentTomlEncodeScenario(w, s)
 
 	default:
 		panic(fmt.Sprintf("unhandled scenario type %q", s.scenarioType))
@@ -704,6 +892,60 @@ func TestTomlScenarios(t *testing.T) {
 	documentScenarios(t, "usage", "toml", genericScenarios, documentTomlScenario)
 }
 
+func TestTomlEncodeJsonKeepsRootArrayBeforeTables(t *testing.T) {
+	scenario := formatScenario{
+		description: "Encode: JSON root array stays outside later tables",
+		input: `{
+  "_source": {
+    "cookie": [
+      {
+        "Domain": "",
+        "Expires": "0001-01-01T00:00:00Z",
+        "HttpOnly": false,
+        "MaxAge": 0,
+        "Name": "name",
+        "Path": "",
+        "Raw": "",
+        "RawExpires": "",
+        "SameSite": 0,
+        "Secure": false,
+        "Unparsed": null,
+        "Value": "value"
+      }
+    ]
+  },
+  "highlight": {
+    "did": [
+      "did"
+    ]
+  },
+  "sort": [
+    1
+  ]
+}`,
+		expected: `sort = [1]
+
+[[_source.cookie]]
+Domain = ""
+Expires = "0001-01-01T00:00:00Z"
+HttpOnly = false
+MaxAge = 0
+Name = "name"
+Path = ""
+Raw = ""
+RawExpires = ""
+SameSite = 0
+Secure = false
+Value = "value"
+
+[highlight]
+did = ["did"]
+`,
+	}
+
+	test.AssertResultWithContext(t, scenario.expected, mustProcessFormatScenario(scenario, NewJSONDecoder(), NewTomlEncoder()), scenario.description)
+}
+
 // TestTomlColourization tests that colourization correctly distinguishes
 // between table section headers and inline arrays
 func TestTomlColourization(t *testing.T) {

project-words.txt

@@ -298,4 +298,9 @@ subsubarray
 Ffile
 Fquery
 coverpkg
-gsub
+gsub
+ralia
+Austr
+ustrali
+héllo
+alia

release_instructions.txt

@@ -8,6 +8,15 @@
 - git push --tags
 - use github actions to publish docker and make github release
 - check github updated yq action in marketplace
+- update github-action/Dockerfile to pin the newly published docker image digest:
+    skopeo inspect docker://docker.io/mikefarah/yq:4 | python3 -c "import sys,json; d=json.load(sys.stdin); print(d['Digest'])"
+  then update the FROM line in github-action/Dockerfile with the new digest:
+    FROM mikefarah/yq:4@sha256:<new-digest>
+
+// release artifacts are signed with cosign keyless signing (Sigstore)
+// users can verify with:
+//   cosign verify-blob --bundle checksums.bundle checksums
+// install cosign: brew install cosign  OR  go install github.com/sigstore/cosign/v2/cmd/cosign@latest
 
 
 - snapcraft

release_notes.txt

@@ -1,3 +1,19 @@
+4.53.2:
+  - Fixing release process
+  
+4.53.1:
+  - Releases and tags now signed and immutable!
+  - Add system(command; args) operator (disabled by default) (#2640)
+  - TOML encoder: prefer readable table sections over inline tables (#2649)
+  - Fix TOML encoder to quote keys containing special characters (#2648)
+  - Add string slicing support (#2639)
+  - Fix findInArray misuse on MappingNodes in equality and contains (#2645) Thanks @jandubois!
+  - Fix panic on negative slice indices that underflow after adjustment (#2646) Thanks @jandubois!
+  - Fix stack overflow from circular alias in traverse (#2647) Thanks @jandubois!
+  - Fix panic and OOM in repeatString for large repeat counts (#2644) Thanks @jandubois!
+  - Bumped dependencies
+
+
 4.52.5:
   - Fix: reset TOML decoder state between files (#2634) thanks @terminalchai
   - Fix: preserve original filename when using --front-matter (#2613) thanks @cobyfrombrooklyn-bot

scripts/bump-version.sh

@@ -49,5 +49,5 @@ fi
 
 git add cmd/version.go snap/snapcraft.yaml
 git commit -m 'Bumping version'
-git tag $version
-git tag -f v4
+git tag $version -m "releasing"
+git tag -f v4 -m "releasing $version"

scripts/xcompile.sh

@@ -4,7 +4,7 @@ set -eo pipefail
 
 # You may need to go install github.com/goreleaser/goreleaser/v2@latest first
 GORELEASER="goreleaser build --clean"
-if [ -z "$CI" ]; then
+if [ -z "$CI" ] || [[ "${GITHUB_REF_NAME:-}" == draft-* ]]; then
   GORELEASER+=" --snapshot"
 fi
 

snap/snapcraft.yaml

@@ -1,5 +1,5 @@
 name: yq
-version: 'v4.52.5'
+version: 'v4.53.2'
 summary: A lightweight and portable command-line data file processor
 description: |
   `yq` uses [jq](https://github.com/stedolan/jq) like syntax but works with yaml, json, xml, csv, properties and TOML files.
@@ -32,6 +32,6 @@ parts:
     build-environment:
       - CGO_ENABLED: 0
     source: https://github.com/mikefarah/yq.git
-    source-tag: v4.52.5
+    source-tag: v4.53.2
     build-snaps:
       - go/latest/stable