chore: bump version to 6.5.0 in package.json and package-lock.json (#762)

* chore: bump version to 6.5.0 in package.json and package-lock.json

* chore: update README.md for improved clarity and structure

* License update

.github/workflows/microsoft-validation.yml

@@ -0,0 +1,143 @@
+name: Validate Microsoft build of Go
+
+on:
+  push:
+    branches:
+      - main
+    paths-ignore:
+      - '**.md'
+  pull_request:
+    paths-ignore:
+      - '**.md'
+
+jobs:
+  microsoft-basic:
+    name: 'Microsoft build of Go ${{ matrix.go-version }} on ${{ matrix.os }}'
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+        go-version: ['1.25', '1.24']
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Setup Microsoft build of Go ${{ matrix.go-version }}
+        uses: ./
+        with:
+          go-version: ${{ matrix.go-version }}
+          go-download-base-url: 'https://aka.ms/golang/release/latest'
+          cache: false
+
+      - name: Verify Go installation
+        run: go version
+
+      - name: Verify Go env
+        run: go env
+
+      - name: Verify Go is functional
+        shell: bash
+        run: |
+          # Create a simple Go program and run it
+          mkdir -p /tmp/test-go && cd /tmp/test-go
+          cat > main.go << 'EOF'
+          package main
+          import "fmt"
+          func main() {
+            fmt.Println("Hello from Microsoft build of Go!")
+          }
+          EOF
+          go run main.go
+
+  microsoft-env-var:
+    name: 'Microsoft build of Go via env var on ${{ matrix.os }}'
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+    env:
+      GO_DOWNLOAD_BASE_URL: 'https://aka.ms/golang/release/latest'
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Setup Microsoft build of Go via environment variable
+        uses: ./
+        with:
+          go-version: '1.25'
+          cache: false
+
+      - name: Verify Go installation
+        run: go version
+
+      - name: Verify Go is functional
+        shell: bash
+        run: |
+          mkdir -p /tmp/test-go && cd /tmp/test-go
+          cat > main.go << 'EOF'
+          package main
+          import "fmt"
+          func main() {
+            fmt.Println("Hello from Microsoft build of Go via env var!")
+          }
+          EOF
+          go run main.go
+
+  microsoft-architecture:
+    name: 'Microsoft build of Go arch ${{ matrix.architecture }} on ${{ matrix.os }}'
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+        architecture: [x64]
+        include:
+          - os: macos-latest
+            architecture: arm64
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Setup Microsoft build of Go with architecture
+        uses: ./
+        with:
+          go-version: '1.25'
+          go-download-base-url: 'https://aka.ms/golang/release/latest'
+          architecture: ${{ matrix.architecture }}
+          cache: false
+
+      - name: Verify Go installation
+        run: go version
+
+  microsoft-with-cache:
+    name: 'Microsoft build of Go with caching on ${{ matrix.os }}'
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Setup Microsoft build of Go with caching
+        uses: ./
+        with:
+          go-version: '1.25'
+          go-download-base-url: 'https://aka.ms/golang/release/latest'
+          cache: true
+
+      - name: Verify Go installation
+        run: go version
+
+      - name: Verify Go is functional
+        shell: bash
+        run: |
+          mkdir -p /tmp/test-go && cd /tmp/test-go
+          go mod init test
+          cat > main.go << 'EOF'
+          package main
+          import "fmt"
+          func main() {
+            fmt.Println("Hello from cached Microsoft build of Go!")
+          }
+          EOF
+          go run main.go

.github/workflows/publish-immutable-actions.yml

@@ -14,7 +14,7 @@ jobs:
 
     steps:
       - name: Checking out
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Publish
         id: publish
         uses: actions/publish-immutable-action@v0.0.4

.github/workflows/release-new-action-version.yml

@@ -22,7 +22,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Update the ${{ env.TAG_NAME }} tag
-        uses: actions/publish-action@v0.3.0
+        uses: actions/publish-action@v0.4.0
         with:
           source-tag: ${{ env.TAG_NAME }}
           slack-webhook: ${{ secrets.SLACK_WEBHOOK }}

.github/workflows/versions.yml

@@ -18,9 +18,9 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest, macos-13]
+        os: [ubuntu-latest, windows-latest, macos-latest, macos-latest-large]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Setup Go Stable
         uses: ./
         with:
@@ -33,9 +33,9 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest, macos-13]
+        os: [ubuntu-latest, windows-latest, macos-latest, macos-latest-large]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Setup Go oldStable
         uses: ./
         with:
@@ -48,16 +48,16 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest, macos-13]
+        os: [ubuntu-latest, windows-latest, macos-latest, macos-latest-large]
         version: [stable, oldstable]
         architecture: [x64, x32]
         exclude:
           - os: macos-latest
             architecture: x32
-          - os: macos-13
+          - os: macos-latest-large
             architecture: x32
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Setup Go ${{ matrix.version }} ${{ matrix.architecture }}
         uses: ./
         with:
@@ -72,7 +72,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [macos-latest, windows-latest, ubuntu-latest, macos-13]
+        os: [macos-latest, windows-latest, ubuntu-latest, macos-latest-large]
         go: [1.21.13, 1.22.8, 1.23.2]
         include:
           - os: windows-latest
@@ -82,7 +82,7 @@ jobs:
             go: 1.23.2
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: setup-go ${{ matrix.go }}
         uses: ./
@@ -98,10 +98,10 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest, macos-13]
+        os: [ubuntu-latest, windows-latest, macos-latest, macos-latest-large]
         go-version: ['1.20', '1.21', '1.22', '1.23']
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Setup Go and check latest
         uses: ./
         with:
@@ -115,9 +115,9 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest, macos-13]
+        os: [ubuntu-latest, windows-latest, macos-latest, macos-latest-large]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Setup Go and check latest
         uses: ./
         with:
@@ -131,9 +131,9 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest, macos-13]
+        os: [ubuntu-latest, windows-latest, macos-latest, macos-latest-large]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Setup Go and check latest
         uses: ./
         with:
@@ -142,16 +142,48 @@ jobs:
         run: __tests__/verify-go.sh 1.21
         shell: bash
 
+  go-version-file-with-tool-versions:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest, macos-latest-large]
+    steps:
+      - uses: actions/checkout@v6
+      - name: Setup Go and check latest
+        uses: ./
+        with:
+          go-version-file: __tests__/data/.tool-versions
+      - name: verify go
+        run: __tests__/verify-go.sh 1.23.2
+        shell: bash
+
+  go-version-file-with-go-version:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest, macos-latest-large]
+    steps:
+      - uses: actions/checkout@v6
+      - name: Setup Go from .go-version file
+        uses: ./
+        with:
+          go-version-file: __tests__/data/.go-version
+      - name: verify go
+        run: __tests__/verify-go.sh 1.22.4
+        shell: bash
+
   setup-versions-from-manifest:
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
-        os: [macos-latest, windows-latest, ubuntu-latest, macos-13]
+        os: [macos-latest, windows-latest, ubuntu-latest, macos-latest-large]
         go: [1.20.14, 1.21.10, 1.22.8, 1.23.2]
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: setup-go ${{ matrix.go }}
         uses: ./
@@ -167,11 +199,11 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [windows-latest, ubuntu-latest, macos-13]
+        os: [windows-latest, ubuntu-latest, macos-latest-large]
         go: [1.11.12]
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: setup-go ${{ matrix.go }}
         uses: ./
@@ -187,7 +219,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest, macos-13]
+        os: [ubuntu-latest, windows-latest, macos-latest, macos-latest-large]
         go-version: [1.20.14, 1.21, 1.22, 1.23]
         include:
           - os: macos-latest
@@ -196,10 +228,10 @@ jobs:
             architecture: x64
           - os: windows-latest
             architecture: x64
-          - os: macos-13
+          - os: macos-latest-large
             architecture: x64
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Setup Go and check latest
         uses: ./
         with:

.github/workflows/windows-validation.yml

@@ -19,7 +19,7 @@ jobs:
         cache: [false, true]
         go: [1.20.1]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: 'Setup ${{ matrix.cache }}, cache: ${{ matrix.go }}'
         uses: ./
@@ -88,7 +88,7 @@ jobs:
       matrix:
         cache: [false, true]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: 'Setup default go, cache: ${{ matrix.cache }}'
         uses: ./
@@ -121,7 +121,7 @@ jobs:
         cache: [false]
         go: [1.20.1]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - name: 'Setup ${{ matrix.go }}, cache: ${{ matrix.cache }}'
         uses: ./

.licensed.yml

@@ -13,3 +13,4 @@ allowed:
 
 reviewed:
   npm:
+     - "@actions/http-client"

README.md

@@ -3,68 +3,96 @@
 [![Basic validation](https://github.com/actions/setup-go/actions/workflows/basic-validation.yml/badge.svg)](https://github.com/actions/setup-go/actions/workflows/basic-validation.yml)
 [![Validate 'setup-go'](https://github.com/actions/setup-go/actions/workflows/versions.yml/badge.svg)](https://github.com/actions/setup-go/actions/workflows/versions.yml)
 
-This action sets up a go environment for use in actions by:
+This action sets up a Go environment for use in GitHub Actions by:
 
-- Optionally downloading and caching a version of Go by version and adding to `PATH`.
+- Optionally downloading and caching a version of Go by version and adding it to the PATH
-- Registering problem matchers for error output.
+- Optionally caching Go modules and build outputs
+- Registering problem matchers for error output
 
-# V5
+## Breaking changes in V6
 
-The V5 edition of the action offers:
+The V6 edition of the action includes:
+- **Upgraded Node.js runtime from node20 to node24**
+  > Make sure your runner is on version v2.327.1 or later to ensure compatibility with this release. See [Release Notes](https://github.com/actions/runner/releases/tag/v2.327.1)
 
-- Upgraded Node.js runtime from node16 to node20
+- **Go toolchain**
+  - Supports both `go` and `toolchain` directives in `go.mod`. If the `toolchain` directive is present, its version is used; otherwise, the action falls back to the `go` directive.
+
+- **Cache key update**
+  - By default, the cache key for Go modules is based on `go.mod`. To use `go.sum`, configure the `cache-dependency-path` input.
 
 See full release notes on the [releases page](https://github.com/actions/setup-go/releases).
 
-# V4
+## Usage
 
-The V4 edition of the action offers:
+See [action.yml](action.yml).
 
- - Enabled caching by default
+<!-- start usage -->
+```yaml
+- uses: actions/setup-go@v6
+  with:
+    # Version or version range of Go to use
+    go-version: '1.23'
     
-The action will try to enable caching unless the `cache` input is explicitly set to false.
+    # Path to go.mod, go.work, .go-version, or .tool-versions file
+    # Note: if both go-version and go-version-file are provided, go-version takes precedence.
+    go-version-file: 'go.mod'
     
-Please see "[Caching dependency files and build outputs](https://github.com/actions/setup-go#caching-dependency-files-and-build-outputs)" for more information.
+    # Set this option if you want the action to check for the latest available version
+    # Default: false
+    check-latest: false
     
-# V3
+    # GitHub token for authentication
+    token: ${{ github.token }}
     
-The V3 edition of the action offers:
+    # Used to specify whether caching is needed.
+    # Default: true
+    cache: true
     
-- Adds `GOBIN` to the `PATH`
+    # Path to dependency files for caching
-- Proxy support
+    cache-dependency-path: 'go.sum'
-- Check latest version
-- Caching packages dependencies
-- stable and oldstable aliases
-- Bug Fixes (including issues around version matching and semver)
     
-The action will first check the local cache for a version match. If a version is not found locally, it will pull it from
+    # Architecture to install (auto-detected if not specified)
-the `main` branch of the [go-versions](https://github.com/actions/go-versions/blob/main/versions-manifest.json)
+    architecture: 'x64'
-repository. On miss or failure, it will fall back to downloading directly
-from [go dist](https://storage.googleapis.com/golang). To change the default behavior, please use
-the [check-latest input](#check-latest-version).
     
-**Note:** The `setup-go` action uses executable binaries which are built by Golang side. The action does not build
+    # Custom base URL for Go downloads (e.g., for mirrors)
-golang from source code.
+    go-download-base-url: ''
+```
+<!-- end usage -->
 
-Matching by [semver spec](https://github.com/npm/node-semver):
+**Basic:**
 
 ```yaml
 steps:
-  - uses: actions/checkout@v5
+  - uses: actions/checkout@v6
   - uses: actions/setup-go@v6
     with:
-      go-version: '^1.13.1' # The Go version to download (if necessary) and use.
+      go-version: '1.25' # The Go version to download (if necessary) and use.
-  - run: go version
+  - run: go run hello.go
 ```
 
-```yaml
+**Version resolution behavior:**
-steps:
+
-  - uses: actions/checkout@v5
+The action resolves the requested version in the following order:
-  - uses: actions/setup-go@v6
+1. **Local cache** - Checks the local tool cache for a matching [semver](https://github.com/npm/node-semver#versions) version.
-    with:
+2. **go-versions repository** - If the requested version isn’t available in the tool cache, it pulls the version manifest from the `main` branch of the [go-versions repository](https://github.com/actions/go-versions/blob/main/versions-manifest.json).
-      go-version: '>=1.17.0'
+3. **Direct download** - If that lookup misses or fails, it will fall back to downloading directly from the [official Go distribution site](https://go.dev/dl).
-  - run: go version
+
-```
+To change the default behavior, please use
+the [check-latest input](docs/advanced-usage.md#check-latest-version).
+
+> **Note**: The `setup-go` action uses executable binaries built by the Go team and does not build Go binaries from source code.
+
+## Supported version syntax
+
+The `go-version` input supports the following syntax:
+
+- Specific versions: `1.25`, `1.24.11`, `1.24.0-rc.1`, `1.23.0-beta.1`
+- SemVer version range syntax: `^1.25.1`, `~1.24.1`, `>=1.25.0-rc.1`, `<1.25.0`, `>=1.22.0 <1.24.0`
+- Aliases: `stable`, `oldstable`
+- Wildcards: `1.25.x`, `1.x`
+
+For details on Semantic Versioning, see [the semver package documentation](https://github.com/npm/node-semver).
 
 > **Note**: Due to the peculiarities of YAML parsing, it is recommended to wrap the version in single quotation marks:
 >
@@ -72,201 +100,9 @@ steps:
 >   go-version: '1.20'
 > ```
 >
-> The recommendation is based on the YAML parser's behavior, which interprets non-wrapped values as numbers and, in the case of version 1.20, trims it down to 1.2, which may not be very obvious.
+> The recommendation is based on the YAML parser's behavior, which interprets non-wrapped values as numbers and, in the case of version `1.20`, trims it down to `1.2`, which may not be very obvious.
 
-Matching an unstable pre-release:
+For more usage examples, please refer to the section: [Using go-version input](docs/advanced-usage.md#using-the-go-version-input) of the [Advanced usage](docs/advanced-usage.md) guide.
-
-```yaml
-steps:
-  - uses: actions/checkout@v5
-  - uses: actions/setup-go@v6
-    with:
-      go-version: '1.18.0-rc.1' # The Go version to download (if necessary) and use.
-  - run: go version
-```
-
-```yaml
-steps:
-  - uses: actions/checkout@v5
-  - uses: actions/setup-go@v6
-    with:
-      go-version: '1.16.0-beta.1' # The Go version to download (if necessary) and use.
-  - run: go version
-```
-
-# Usage
-
-See [action.yml](action.yml)
-
-## Basic
-
-```yaml
-steps:
-  - uses: actions/checkout@v5
-  - uses: actions/setup-go@v6
-    with:
-      go-version: '1.16.1' # The Go version to download (if necessary) and use.
-  - run: go run hello.go
-```
-
-## Check latest version
-
-The `check-latest` flag defaults to `false`. Use the default or set `check-latest` to `false` if you prefer stability
-and if you want to ensure a specific Go version is always used.
-
-If `check-latest` is set to `true`, the action first checks if the cached version is the latest one. If the locally
-cached version is not the most up-to-date, a Go version will then be downloaded. Set `check-latest` to `true` if you
-want the most up-to-date Go version to always be used.
-
-> Setting `check-latest` to `true` has performance implications as downloading Go versions is slower than using cached
-> versions.
-
-```yaml
-steps:
-  - uses: actions/checkout@v5
-  - uses: actions/setup-go@v6
-    with:
-      go-version: '1.14'
-      check-latest: true
-  - run: go run hello.go
-```
-
-## Using stable/oldstable aliases
-
-If `stable` is provided, action will get the latest stable version from
-the [`go-versions`](https://github.com/actions/go-versions/blob/main/versions-manifest.json) repository manifest.
-
-If `oldstable` is provided, when current release is 1.19.x, action will resolve version as 1.18.x, where x is the latest
-patch release.
-
-**Note:** using these aliases will result in same version as using corresponding minor release with `check-latest` input
-set to `true`
-
-```yaml
-steps:
-  - uses: actions/checkout@v5
-  - uses: actions/setup-go@v6
-    with:
-      go-version: 'stable'
-  - run: go run hello.go
-```
-
-```yaml
-steps:
-  - uses: actions/checkout@v5
-  - uses: actions/setup-go@v6
-    with:
-      go-version: 'oldstable'
-  - run: go run hello.go
-```
-
-## Caching dependency files and build outputs:
-
-The action has a built-in functionality for caching and restoring go modules and build outputs. It
-uses [toolkit/cache](https://github.com/actions/toolkit/tree/main/packages/cache) under the hood but requires less configuration settings.
-The `cache` input is optional, and caching is turned on by default.
-
-The action defaults to search for the dependency file - go.sum in the repository root, and uses its hash as a part of
-the cache key. Use `cache-dependency-path` input for cases when multiple dependency files are used, or they are located
-in different subdirectories. The input supports glob patterns.
-
-If some problem that prevents success caching happens then the action issues the warning in the log and continues the execution of the pipeline.
-
-**Caching in monorepos**
-
-```yaml
-steps:
-  - uses: actions/checkout@v5
-  - uses: actions/setup-go@v6
-    with:
-      go-version: '1.17'
-      check-latest: true
-      cache-dependency-path: |
-             subdir/go.sum
-             tools/go.sum
-    # cache-dependency-path: "**/*.sum"
-
-  - run: go run hello.go
-  ```
-
-## Getting go version from the go.mod file
-
-The `go-version-file` input accepts a path to a `go.mod` file or a `go.work`
-file that contains the version of Go to be used by a project. The version taken
-from thils file will be:
-
-  - The version from the `toolchain` directive, if there is one, otherwise
-  - The version from the `go` directive
-
-The version can specify a patch version or omit it altogether (e.g., `go 1.22.0` or `go 1.22`).
-
-If a patch version is specified, that specific patch version will be used.  
-If no patch version is specified, it will search for the latest available patch version in the cache,
-[versions-manifest.json](https://github.com/actions/go-versions/blob/main/versions-manifest.json), and the
-[official Go language website](https://golang.org/dl/?mode=json&include=all), in that order.
-
-If both the `go-version` and the `go-version-file` inputs are provided then the `go-version` input is used.
-> The action will search for the `go.mod` file relative to the repository root
-
-```yaml
-steps:
-  - uses: actions/checkout@v5
-  - uses: actions/setup-go@v6
-    with:
-      go-version-file: 'path/to/go.mod'
-  - run: go version
-```
-
-## Matrix testing
-
-```yaml
-jobs:
-  build:
-    runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        go: [ '1.14', '1.13' ]
-    name: Go ${{ matrix.go }} sample
-    steps:
-      - uses: actions/checkout@v5
-      - name: Setup go
-        uses: actions/setup-go@v6
-        with:
-          go-version: ${{ matrix.go }}
-      - run: go run hello.go
-```
-
-### Supported version syntax
-
-The `go-version` input supports the following syntax:
-
-- Specific versions: `1.15`, `1.16.1`, `1.17.0-rc.2`, `1.16.0-beta.1`
-- SemVer's version range syntax: `^1.13.1`, `>=1.18.0-rc.1`
-
-For more information about semantic versioning, please refer to [semver](https://github.com/npm/node-semver)
-documentation.
-
-## Using `setup-go` on GHES
-
-`setup-go` comes pre-installed on the appliance with GHES if Actions is enabled.
-When dynamically downloading Go distributions, `setup-go` downloads distributions from [`actions/go-versions`](https://github.com/actions/go-versions) on github.com (outside of the appliance).
-
-These calls to `actions/go-versions` are made via unauthenticated requests, which are limited to [60 requests per hour per IP](https://docs.github.com/en/rest/overview/resources-in-the-rest-api#rate-limiting).
-If more requests are made within the time frame, then the action leverages the `raw API` to retrieve the version-manifest. This approach does not impose a rate limit and hence facilitates unrestricted consumption. This is particularly beneficial for GHES runners, which often share the same IP, to avoid the quick exhaustion of the unauthenticated rate limit.
-If that fails as well the action will try to download versions directly from https://storage.googleapis.com/golang.
-
-If that fails as well you can get a higher rate limit with [generating a personal access token on github.com](https://github.com/settings/tokens/new) and passing it as the `token` input to the action:
-
-```yaml
-uses: actions/setup-go@v6
-with:
-  token: ${{ secrets.GH_DOTCOM_TOKEN }}
-  go-version: '1.18'
-```
-
-If the runner is not able to access github.com, any Go versions requested during a workflow run must come from the runner's tool cache.
-See "[Setting up the tool cache on self-hosted runners without internet access](https://docs.github.com/en/enterprise-server@3.2/admin/github-actions/managing-access-to-actions-from-githubcom/setting-up-the-tool-cache-on-self-hosted-runners-without-internet-access)"
-for more information.
 
 ## Recommended permissions
 
@@ -277,13 +113,36 @@ permissions:
   contents: read # access to check out code and install dependencies
 ```
 
-# License
+## Caching dependency files and build outputs
 
-The scripts and documentation in this project are released under the [MIT License](LICENSE)
+The action includes built-in caching and restoration for Go modules and build outputs. It uses
+[toolkit/cache](https://github.com/actions/toolkit/tree/main/packages/cache) under the hood, but requires less configuration.
+The `cache` input is optional, and caching is enabled by default. To disable caching, set `cache: false`.
 
-# Contributions
+By default, the action looks for `go.mod` in the repository root and uses its hash as part of the cache key. Use the `cache-dependency-path` input when you have multiple dependency files, or when they’re located in different subdirectories. This input supports glob patterns.
 
-Contributions are welcome! See [Contributor's Guide](docs/contributors.md)
+If caching cannot be performed for any reason, the action logs a warning and continues workflow execution.
+
+For examples of using `cache-dependency-path`, see the [Caching](docs/advanced-usage.md#caching) section of the [Advanced usage](docs/advanced-usage.md) guide.
+
+
+## Advanced usage
+
+- [Using the go-version input](docs/advanced-usage.md#using-the-go-version-input)
+- [Using the go-version-file input](docs/advanced-usage.md#using-the-go-version-file-input)
+- [Check latest version](docs/advanced-usage.md#check-latest-version)
+- [Caching](docs/advanced-usage.md#caching)
+- [Outputs](docs/advanced-usage.md#outputs)
+- [Custom download URL](docs/advanced-usage.md#custom-download-url)
+- [Using `setup-go` on GHES](docs/advanced-usage.md#using-setup-go-on-ghes)
+
+## License
+
+The scripts and documentation in this project are released under the [MIT License](LICENSE).
+
+## Contributions
+
+Contributions are welcome! See our [Contributor's Guide](docs/contributors.md).
 
 ## Code of Conduct
 

__tests__/cache-restore.test.ts

@@ -1,93 +1,82 @@
 import * as cache from '@actions/cache';
 import * as core from '@actions/core';
 import * as glob from '@actions/glob';
+import fs from 'fs';
 
 import * as cacheRestore from '../src/cache-restore';
 import * as cacheUtils from '../src/cache-utils';
 import {PackageManagerInfo} from '../src/package-managers';
 
 describe('restoreCache', () => {
-  //Arrange
+  let hashFilesSpy: jest.SpyInstance;
-  const hashFilesSpy = jest.spyOn(glob, 'hashFiles');
+  let getCacheDirectoryPathSpy: jest.SpyInstance;
-  const getCacheDirectoryPathSpy = jest.spyOn(
+  let restoreCacheSpy: jest.SpyInstance;
-    cacheUtils,
+  let infoSpy: jest.SpyInstance;
-    'getCacheDirectoryPath'
+  let setOutputSpy: jest.SpyInstance;
-  );
-  const restoreCacheSpy = jest.spyOn(cache, 'restoreCache');
-  const infoSpy = jest.spyOn(core, 'info');
-  const setOutputSpy = jest.spyOn(core, 'setOutput');
 
   const versionSpec = '1.13.1';
   const packageManager = 'default';
   const cacheDependencyPath = 'path';
 
+  let originalWorkspace: string | undefined;
+
   beforeEach(() => {
+    originalWorkspace = process.env.GITHUB_WORKSPACE;
+    process.env.GITHUB_WORKSPACE = '/test/workspace';
+    //Arrange
+    hashFilesSpy = jest.spyOn(glob, 'hashFiles');
+    getCacheDirectoryPathSpy = jest.spyOn(cacheUtils, 'getCacheDirectoryPath');
+    restoreCacheSpy = jest.spyOn(cache, 'restoreCache');
+    infoSpy = jest.spyOn(core, 'info');
+    setOutputSpy = jest.spyOn(core, 'setOutput');
+
     getCacheDirectoryPathSpy.mockImplementation(
       (PackageManager: PackageManagerInfo) => {
-        return new Promise<string[]>(resolve => {
+        return Promise.resolve([
-          resolve(['cache_directory_path', 'cache_directory_path']);
+          'cache_directory_path',
-        });
+          'cache_directory_path'
+        ]);
       }
     );
   });
 
-  it('should throw if dependency file path is not valid', async () => {
+  afterEach(() => {
-    //Arrange
+    process.env.GITHUB_WORKSPACE = originalWorkspace;
-    hashFilesSpy.mockImplementation((somePath: string) => {
+    jest.restoreAllMocks();
-      return new Promise<string>(resolve => {
-        resolve('');
-      });
   });
 
+  it('should throw if dependency file path is not valid', async () => {
+    // Arrange
+    hashFilesSpy.mockImplementation(() => Promise.resolve(''));
     // Act + Assert
-    await expect(async () => {
+    await expect(
-      await cacheRestore.restoreCache(
+      cacheRestore.restoreCache(
         versionSpec,
         packageManager,
         cacheDependencyPath
-      );
+      )
-    }).rejects.toThrow(
+    ).rejects.toThrow(
       'Some specified paths were not resolved, unable to cache dependencies.'
     );
   });
 
-  it('should inform if cache hit is not occured', async () => {
+  it('should inform if cache hit is not occurred', async () => {
     // Arrange
-    hashFilesSpy.mockImplementation((somePath: string) => {
+    hashFilesSpy.mockImplementation(() => Promise.resolve('file_hash'));
-      return new Promise<string>(resolve => {
+    restoreCacheSpy.mockImplementation(() => Promise.resolve(''));
-        resolve('file_hash');
-      });
-    });
-
-    restoreCacheSpy.mockImplementation(() => {
-      return new Promise<string>(resolve => {
-        resolve('');
-      });
-    });
-
     // Act + Assert
     await cacheRestore.restoreCache(
       versionSpec,
       packageManager,
       cacheDependencyPath
     );
-    expect(infoSpy).toHaveBeenCalledWith(`Cache is not found`);
+    expect(infoSpy).toHaveBeenCalledWith('Cache is not found');
   });
 
-  it('should set output if cache hit is occured', async () => {
+  it('should set output if cache hit is occurred', async () => {
     // Arrange
-    hashFilesSpy.mockImplementation((somePath: string) => {
+    hashFilesSpy.mockImplementation(() => Promise.resolve('file_hash'));
-      return new Promise<string>(resolve => {
+    restoreCacheSpy.mockImplementation(() => Promise.resolve('cache_key'));
-        resolve('file_hash');
-      });
-    });
-
-    restoreCacheSpy.mockImplementation(() => {
-      return new Promise<string>(resolve => {
-        resolve('cache_key');
-      });
-    });
-
     // Act + Assert
     await cacheRestore.restoreCache(
       versionSpec,
@@ -96,4 +85,18 @@ describe('restoreCache', () => {
     );
     expect(setOutputSpy).toHaveBeenCalledWith('cache-hit', true);
   });
+
+  it('should throw if dependency file is not found in workspace', async () => {
+    jest.spyOn(fs, 'readdirSync').mockReturnValue(['main.go'] as any);
+
+    await expect(
+      cacheRestore.restoreCache(
+        versionSpec,
+        packageManager
+        // No cacheDependencyPath
+      )
+    ).rejects.toThrow(
+      'Dependencies file is not found in /test/workspace. Supported file pattern: go.mod'
+    );
+  });
 });

__tests__/cache-save.test.ts

@@ -0,0 +1,155 @@
+import * as cache from '@actions/cache';
+import * as core from '@actions/core';
+import fs from 'fs';
+
+import {run} from '../src/cache-save';
+import * as cacheUtils from '../src/cache-utils';
+import {State} from '../src/constants';
+
+describe('cache-save', () => {
+  const primaryKey = 'primary-key';
+
+  let primaryKeyValue: string;
+  let matchedKeyValue: string;
+
+  let getBooleanInputSpy: jest.SpyInstance;
+  let getStateSpy: jest.SpyInstance;
+  let infoSpy: jest.SpyInstance;
+  let warningSpy: jest.SpyInstance;
+  let debugSpy: jest.SpyInstance;
+  let setFailedSpy: jest.SpyInstance;
+  let saveCacheSpy: jest.SpyInstance;
+  let getCacheDirectoryPathSpy: jest.SpyInstance;
+  let existsSpy: jest.SpyInstance;
+
+  beforeEach(() => {
+    primaryKeyValue = primaryKey;
+    matchedKeyValue = 'matched-key';
+
+    getBooleanInputSpy = jest.spyOn(core, 'getBooleanInput');
+    getBooleanInputSpy.mockReturnValue(true);
+
+    getStateSpy = jest.spyOn(core, 'getState');
+    getStateSpy.mockImplementation((key: string) => {
+      if (key === State.CachePrimaryKey) {
+        return primaryKeyValue;
+      }
+      if (key === State.CacheMatchedKey) {
+        return matchedKeyValue;
+      }
+      return '';
+    });
+
+    infoSpy = jest.spyOn(core, 'info');
+    infoSpy.mockImplementation(() => undefined);
+
+    warningSpy = jest.spyOn(core, 'warning');
+    warningSpy.mockImplementation(() => undefined);
+
+    debugSpy = jest.spyOn(core, 'debug');
+    debugSpy.mockImplementation(() => undefined);
+
+    setFailedSpy = jest.spyOn(core, 'setFailed');
+    setFailedSpy.mockImplementation(() => undefined);
+
+    saveCacheSpy = jest.spyOn(cache, 'saveCache');
+    saveCacheSpy.mockImplementation(() => Promise.resolve(0));
+
+    getCacheDirectoryPathSpy = jest.spyOn(cacheUtils, 'getCacheDirectoryPath');
+    getCacheDirectoryPathSpy.mockImplementation(() =>
+      Promise.resolve(['cache_directory_path', 'cache_directory_path'])
+    );
+
+    existsSpy = jest.spyOn(fs, 'existsSync');
+    existsSpy.mockImplementation(() => true);
+  });
+
+  afterEach(() => {
+    jest.restoreAllMocks();
+  });
+
+  it('does not save cache when the cache input is false', async () => {
+    getBooleanInputSpy.mockReturnValue(false);
+
+    await run();
+
+    expect(saveCacheSpy).not.toHaveBeenCalled();
+    expect(warningSpy).not.toHaveBeenCalled();
+    expect(setFailedSpy).not.toHaveBeenCalled();
+  });
+
+  it('does not save cache when there are no cache folders on the disk', async () => {
+    existsSpy.mockImplementation(() => false);
+
+    await run();
+
+    expect(warningSpy).toHaveBeenCalledWith(
+      'There are no cache folders on the disk'
+    );
+    expect(saveCacheSpy).not.toHaveBeenCalled();
+    expect(setFailedSpy).not.toHaveBeenCalled();
+  });
+
+  it('does not save cache when the primary key was not generated', async () => {
+    primaryKeyValue = '';
+
+    await run();
+
+    expect(infoSpy).toHaveBeenCalledWith(
+      'Primary key was not generated. Please check the log messages above for more errors or information'
+    );
+    expect(saveCacheSpy).not.toHaveBeenCalled();
+    expect(setFailedSpy).not.toHaveBeenCalled();
+  });
+
+  it('does not save cache when a cache hit occurred on the primary key', async () => {
+    matchedKeyValue = primaryKey;
+
+    await run();
+
+    expect(infoSpy).toHaveBeenCalledWith(
+      `Cache hit occurred on the primary key ${primaryKey}, not saving cache.`
+    );
+    expect(saveCacheSpy).not.toHaveBeenCalled();
+    expect(setFailedSpy).not.toHaveBeenCalled();
+  });
+
+  it('saves cache when the primary key differs from the matched key', async () => {
+    await run();
+
+    expect(saveCacheSpy).toHaveBeenCalled();
+    expect(infoSpy).toHaveBeenCalledWith(
+      `Cache saved with the key: ${primaryKey}`
+    );
+    expect(warningSpy).not.toHaveBeenCalled();
+    expect(setFailedSpy).not.toHaveBeenCalled();
+  });
+
+  it('save with -1 cacheId , should not fail workflow', async () => {
+    saveCacheSpy.mockImplementation(() => Promise.resolve(-1));
+
+    await run();
+
+    expect(saveCacheSpy).toHaveBeenCalled();
+    expect(debugSpy).toHaveBeenCalledWith(
+      `Cache was not saved for the key: ${primaryKey}`
+    );
+    expect(infoSpy).not.toHaveBeenCalledWith(
+      `Cache saved with the key: ${primaryKey}`
+    );
+    expect(warningSpy).not.toHaveBeenCalled();
+    expect(setFailedSpy).not.toHaveBeenCalled();
+  });
+
+  it('saves with error from toolkit, should not fail workflow', async () => {
+    saveCacheSpy.mockImplementation(() =>
+      Promise.reject(new Error('Unable to reach the service'))
+    );
+
+    await run();
+
+    expect(saveCacheSpy).toHaveBeenCalled();
+    expect(warningSpy).toHaveBeenCalledWith('Unable to reach the service');
+    expect(setFailedSpy).not.toHaveBeenCalled();
+  });
+});

__tests__/cache-utils.test.ts

@@ -47,7 +47,7 @@ describe('getPackageManagerInfo', () => {
     //Arrange
     const packageManagerName = 'default';
     const expectedResult = {
-      dependencyFilePattern: 'go.sum',
+      dependencyFilePattern: 'go.mod',
       cacheFolderCommandList: ['go env GOMODCACHE', 'go env GOCACHE']
     };
 
@@ -73,7 +73,7 @@ describe('getCacheDirectoryPath', () => {
   const getExecOutputSpy = jest.spyOn(exec, 'getExecOutput');
 
   const validPackageManager: PackageManagerInfo = {
-    dependencyFilePattern: 'go.sum',
+    dependencyFilePattern: 'go.mod',
     cacheFolderCommandList: ['go env GOMODCACHE', 'go env GOCACHE']
   };
 

__tests__/data/.go-version

@@ -0,0 +1 @@
+1.22.4

__tests__/data/.tool-versions

@@ -0,0 +1 @@
+golang 1.23.2

__tests__/setup-go.test.ts

@@ -45,6 +45,7 @@ describe('setup-go', () => {
   let mkdirSpy: jest.SpyInstance;
   let symlinkSpy: jest.SpyInstance;
   let execSpy: jest.SpyInstance;
+  let execFileSpy: jest.SpyInstance;
   let getManifestSpy: jest.SpyInstance;
   let getAllVersionsSpy: jest.SpyInstance;
   let httpmGetJsonSpy: jest.SpyInstance;
@@ -71,6 +72,10 @@ describe('setup-go', () => {
     archSpy = jest.spyOn(osm, 'arch');
     archSpy.mockImplementation(() => os['arch']);
     execSpy = jest.spyOn(cp, 'execSync');
+    execFileSpy = jest.spyOn(cp, 'execFileSync');
+    execFileSpy.mockImplementation(() => {
+      throw new Error('ENOENT');
+    });
 
     // switch path join behaviour based on set os.platform
     joinSpy = jest.spyOn(path, 'join');
@@ -129,8 +134,9 @@ describe('setup-go', () => {
   });
 
   afterEach(() => {
-    // clear out env var set during 'run'
+    // clear out env vars set during 'run'
     delete process.env[im.GOTOOLCHAIN_ENV_VAR];
+    delete process.env['GO_DOWNLOAD_BASE_URL'];
 
     //jest.resetAllMocks();
     jest.clearAllMocks();
@@ -389,7 +395,7 @@ describe('setup-go', () => {
 
     const expPath = path.win32.join(toolPath, 'bin');
     expect(dlSpy).toHaveBeenCalledWith(
-      'https://storage.googleapis.com/golang/go1.13.1.windows-amd64.zip',
+      'https://go.dev/dl/go1.13.1.windows-amd64.zip',
       'C:\\temp\\go1.13.1.windows-amd64.zip',
       undefined
     );
@@ -866,6 +872,9 @@ exclude example.com/thismodule v1.3.0
 
 use .
 
+`;
+
+    const toolVersionsContents = `golang 1.23
 `;
 
     it('reads version from go.mod', async () => {
@@ -892,6 +901,18 @@ use .
       expect(logSpy).toHaveBeenCalledWith('matching 1.19...');
     });
 
+    it('reads version from .tool-versions', async () => {
+      inputs['go-version-file'] = '.tool-versions';
+      existsSpy.mockImplementation(() => true);
+      readFileSpy.mockImplementation(() => Buffer.from(toolVersionsContents));
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith('Setup go version spec 1.23');
+      expect(logSpy).toHaveBeenCalledWith('Attempting to download 1.23...');
+      expect(logSpy).toHaveBeenCalledWith('matching 1.23...');
+    });
+
     it('reads version from .go-version', async () => {
       inputs['go-version-file'] = '.go-version';
       existsSpy.mockImplementation(() => true);
@@ -946,7 +967,7 @@ use .
         const expectedUrl =
           platform === 'win32'
             ? `https://github.com/actions/go-versions/releases/download/${version}/go-${version}-${platform}-${arch}.${fileExtension}`
-            : `https://storage.googleapis.com/golang/go${version}.${osSpec}-${arch}.${fileExtension}`;
+            : `https://go.dev/dl/go${version}.${osSpec}-${arch}.${fileExtension}`;
 
         // ... but not in the local cache
         findSpy.mockImplementation(() => '');
@@ -1090,4 +1111,456 @@ use .
     expect(vars).toStrictEqual({GOTOOLCHAIN: 'local'});
     expect(process.env).toHaveProperty('GOTOOLCHAIN', 'local');
   });
+
+  describe('go-download-base-url', () => {
+    it('downloads a version from custom base URL using version listing', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.13.1';
+      const customBaseUrl = 'https://example.com/golang';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = customBaseUrl;
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      const toolPath = path.normalize('/cache/go/1.13.1/x64');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      const expPath = path.join(toolPath, 'bin');
+      expect(logSpy).toHaveBeenCalledWith(
+        `Using custom Go download base URL: ${customBaseUrl}`
+      );
+      expect(logSpy).toHaveBeenCalledWith('Install from custom download URL');
+      // Version listing should use custom base URL, not go.dev
+      expect(getSpy).toHaveBeenCalledWith(
+        `${customBaseUrl}/?mode=json&include=all`
+      );
+      expect(dlSpy).toHaveBeenCalled();
+      expect(extractTarSpy).toHaveBeenCalled();
+      expect(cnSpy).toHaveBeenCalledWith(`::add-path::${expPath}${osm.EOL}`);
+    });
+
+    it('skips version listing for known direct-download URL (aka.ms)', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.25.0';
+      const customBaseUrl = 'https://aka.ms/golang/release/latest';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = customBaseUrl;
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      const toolPath = path.normalize('/cache/go/1.25.0/x64');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      const expPath = path.join(toolPath, 'bin');
+      expect(logSpy).toHaveBeenCalledWith(
+        'Skipping version listing for known direct-download URL. Constructing download URL directly.'
+      );
+      expect(logSpy).toHaveBeenCalledWith(
+        `Constructed direct download URL: ${customBaseUrl}/go1.25.0.linux-amd64.tar.gz`
+      );
+      expect(logSpy).toHaveBeenCalledWith('Install from custom download URL');
+      expect(getSpy).not.toHaveBeenCalled();
+      expect(dlSpy).toHaveBeenCalled();
+      expect(cnSpy).toHaveBeenCalledWith(`::add-path::${expPath}${osm.EOL}`);
+    });
+
+    it('constructs correct direct download URL for windows (aka.ms)', async () => {
+      os.platform = 'win32';
+      os.arch = 'x64';
+
+      const versionSpec = '1.25.0';
+      const customBaseUrl = 'https://aka.ms/golang/release/latest';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = customBaseUrl;
+      process.env['RUNNER_TEMP'] = 'C:\\temp\\';
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => 'C:\\temp\\some\\path');
+      extractZipSpy.mockImplementation(() => 'C:\\temp\\some\\other\\path');
+      const toolPath = path.normalize('C:\\cache\\go\\1.25.0\\x64');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      expect(getSpy).not.toHaveBeenCalled();
+      expect(dlSpy).toHaveBeenCalledWith(
+        `${customBaseUrl}/go1.25.0.windows-amd64.zip`,
+        'C:\\temp\\go1.25.0.windows-amd64.zip',
+        undefined
+      );
+    });
+
+    it('skips manifest and downloads directly from custom URL', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.12.16';
+      const customBaseUrl = 'https://example.com/golang';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = customBaseUrl;
+      inputs['token'] = 'faketoken';
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      const toolPath = path.normalize('/cache/go/1.12.16/x64');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      // Should not try to use the manifest at all
+      expect(logSpy).not.toHaveBeenCalledWith(
+        expect.stringContaining('Not found in manifest')
+      );
+      expect(logSpy).toHaveBeenCalledWith('Install from custom download URL');
+    });
+
+    it('strips trailing slashes from custom base URL', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.13.1';
+      const customBaseUrl = 'https://example.com/golang/';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = customBaseUrl;
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      const toolPath = path.normalize('/cache/go/1.13.1/x64');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith(
+        `Acquiring go1.13.1 from https://example.com/golang/go1.13.1.linux-amd64.tar.gz`
+      );
+    });
+
+    it('reads custom base URL from environment variable', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.13.1';
+      const customBaseUrl = 'https://example.com/golang';
+
+      inputs['go-version'] = versionSpec;
+      process.env['GO_DOWNLOAD_BASE_URL'] = customBaseUrl;
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      const toolPath = path.normalize('/cache/go/1.13.1/x64');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith(
+        `Using custom Go download base URL: ${customBaseUrl}`
+      );
+      expect(logSpy).toHaveBeenCalledWith('Install from custom download URL');
+    });
+
+    it('input takes precedence over environment variable', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.13.1';
+      const inputUrl = 'https://input.example.com/golang';
+      const envUrl = 'https://env.example.com/golang';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = inputUrl;
+      process.env['GO_DOWNLOAD_BASE_URL'] = envUrl;
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      const toolPath = path.normalize('/cache/go/1.13.1/x64');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith(
+        `Using custom Go download base URL: ${inputUrl}`
+      );
+      expect(logSpy).toHaveBeenCalledWith(
+        `Acquiring go1.13.1 from ${inputUrl}/go1.13.1.linux-amd64.tar.gz`
+      );
+    });
+
+    it('errors when stable alias is used with custom URL', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      inputs['go-version'] = 'stable';
+      inputs['go-download-base-url'] = 'https://example.com/golang';
+
+      findSpy.mockImplementation(() => '');
+      await main.run();
+
+      expect(cnSpy).toHaveBeenCalledWith(
+        `::error::Version aliases 'stable' are not supported with a custom download base URL. Please specify an exact Go version.${osm.EOL}`
+      );
+    });
+
+    it('logs info when check-latest is used with custom URL', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.13.1';
+      const customBaseUrl = 'https://example.com/golang';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = customBaseUrl;
+      inputs['check-latest'] = true;
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      const toolPath = path.normalize('/cache/go/1.13.1/x64');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith(
+        'check-latest is not supported with a custom download base URL. Using the provided version spec directly.'
+      );
+    });
+
+    it('constructs direct download info correctly', () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const info = im.getInfoFromDirectDownload(
+        '1.25.0',
+        'x64',
+        'https://aka.ms/golang/release/latest'
+      );
+
+      expect(info.type).toBe('dist');
+      expect(info.downloadUrl).toBe(
+        'https://aka.ms/golang/release/latest/go1.25.0.linux-amd64.tar.gz'
+      );
+      expect(info.fileName).toBe('go1.25.0.linux-amd64.tar.gz');
+      expect(info.resolvedVersion).toBe('1.25.0');
+    });
+
+    it('constructs direct download info for windows', () => {
+      os.platform = 'win32';
+      os.arch = 'x64';
+
+      const info = im.getInfoFromDirectDownload(
+        '1.25.0',
+        'x64',
+        'https://aka.ms/golang/release/latest'
+      );
+
+      expect(info.type).toBe('dist');
+      expect(info.downloadUrl).toBe(
+        'https://aka.ms/golang/release/latest/go1.25.0.windows-amd64.zip'
+      );
+      expect(info.fileName).toBe('go1.25.0.windows-amd64.zip');
+    });
+
+    it('constructs direct download info for arm64', () => {
+      os.platform = 'darwin';
+      os.arch = 'arm64';
+
+      const info = im.getInfoFromDirectDownload(
+        '1.25.0',
+        'arm64',
+        'https://aka.ms/golang/release/latest'
+      );
+
+      expect(info.type).toBe('dist');
+      expect(info.downloadUrl).toBe(
+        'https://aka.ms/golang/release/latest/go1.25.0.darwin-arm64.tar.gz'
+      );
+      expect(info.fileName).toBe('go1.25.0.darwin-arm64.tar.gz');
+    });
+
+    it('caches under actual installed version when it differs from input spec', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.20';
+      const customBaseUrl = 'https://aka.ms/golang/release/latest';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = customBaseUrl;
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+
+      // Mock the installed Go binary reporting a different patch version
+      execFileSpy.mockImplementation(() => 'go version go1.20.14 linux/amd64');
+
+      const expectedToolName = im.customToolCacheName(customBaseUrl);
+      const toolPath = path.normalize(`/cache/${expectedToolName}/1.20.14/x64`);
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      expect(logSpy).toHaveBeenCalledWith(
+        "Requested version '1.20' resolved to installed version '1.20.14'"
+      );
+      // Cache key should use actual version, not the input spec
+      expect(cacheSpy).toHaveBeenCalledWith(
+        expect.any(String),
+        expectedToolName,
+        '1.20.14',
+        'x64'
+      );
+    });
+
+    it('shows clear error with platform/arch and URL on 404', async () => {
+      os.platform = 'linux';
+      os.arch = 'arm64';
+
+      const versionSpec = '1.25.0';
+      const customBaseUrl = 'https://example.com/golang';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = customBaseUrl;
+
+      getSpy.mockImplementationOnce(() => {
+        throw new Error('Not a JSON endpoint');
+      });
+
+      findSpy.mockImplementation(() => '');
+      const httpError = new tc.HTTPError(404);
+      dlSpy.mockImplementation(() => {
+        throw httpError;
+      });
+
+      await main.run();
+
+      expect(cnSpy).toHaveBeenCalledWith(
+        expect.stringContaining(
+          'The requested Go version 1.25.0 is not available for platform linux/arm64'
+        )
+      );
+      expect(cnSpy).toHaveBeenCalledWith(expect.stringContaining('HTTP 404'));
+    });
+
+    it('shows clear error with platform/arch and URL on download failure', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.25.0';
+      const customBaseUrl = 'https://example.com/golang';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = customBaseUrl;
+
+      getSpy.mockImplementationOnce(() => {
+        throw new Error('Not a JSON endpoint');
+      });
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(() => {
+        throw new Error('connection refused');
+      });
+
+      await main.run();
+
+      expect(cnSpy).toHaveBeenCalledWith(
+        expect.stringContaining(
+          'Failed to download Go 1.25.0 for platform linux/x64'
+        )
+      );
+      expect(cnSpy).toHaveBeenCalledWith(
+        expect.stringContaining(customBaseUrl)
+      );
+    });
+
+    it.each(['^1.25.0', '~1.25', '>=1.25.0', '<1.26.0', '1.25.x', '1.x'])(
+      'errors on version range "%s" when version listing is unavailable',
+      async versionSpec => {
+        os.platform = 'linux';
+        os.arch = 'x64';
+
+        inputs['go-version'] = versionSpec;
+        inputs['go-download-base-url'] = 'https://example.com/golang';
+
+        // Simulate version listing not available
+        getSpy.mockImplementationOnce(() => {
+          throw new Error('Not a JSON endpoint');
+        });
+
+        findSpy.mockImplementation(() => '');
+
+        await main.run();
+
+        expect(cnSpy).toHaveBeenCalledWith(
+          expect.stringContaining(
+            `Version range '${versionSpec}' is not supported with a custom download base URL`
+          )
+        );
+      }
+    );
+
+    it('rejects version range in getInfoFromDirectDownload', () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      expect(() =>
+        im.getInfoFromDirectDownload(
+          '^1.25.0',
+          'x64',
+          'https://example.com/golang'
+        )
+      ).toThrow(
+        "Version range '^1.25.0' is not supported with a custom download base URL"
+      );
+    });
+
+    it('passes token as auth header for custom URL downloads', async () => {
+      os.platform = 'linux';
+      os.arch = 'x64';
+
+      const versionSpec = '1.25.0';
+      const customBaseUrl = 'https://private-mirror.example.com/golang';
+
+      inputs['go-version'] = versionSpec;
+      inputs['go-download-base-url'] = customBaseUrl;
+      inputs['token'] = 'ghp_testtoken123';
+
+      getSpy.mockImplementationOnce(() => {
+        throw new Error('Not a JSON endpoint');
+      });
+
+      findSpy.mockImplementation(() => '');
+      dlSpy.mockImplementation(async () => '/some/temp/path');
+      extractTarSpy.mockImplementation(async () => '/some/other/temp/path');
+      const expectedToolName = im.customToolCacheName(customBaseUrl);
+      const toolPath = path.normalize(`/cache/${expectedToolName}/1.25.0/x64`);
+      cacheSpy.mockImplementation(async () => toolPath);
+
+      await main.run();
+
+      expect(dlSpy).toHaveBeenCalledWith(
+        `${customBaseUrl}/go1.25.0.linux-amd64.tar.gz`,
+        undefined,
+        'token ghp_testtoken123'
+      );
+    });
+  });
 });

action.yml

@@ -5,7 +5,7 @@ inputs:
   go-version:
     description: 'The Go version to download (if necessary) and use. Supports semver spec and ranges. Be sure to enclose this option in single quotation marks.'
   go-version-file:
-    description: 'Path to the go.mod or go.work file.'
+    description: 'Path to the go.mod, go.work, .go-version, or .tool-versions file.'
   check-latest:
     description: 'Set this option to true if you want the action to always check for the latest available version that satisfies the version spec'
     default: false
@@ -16,16 +16,18 @@ inputs:
     description: Used to specify whether caching is needed. Set to true, if you'd like to enable caching.
     default: true
   cache-dependency-path:
-    description: 'Used to specify the path to a dependency file - go.sum'
+    description: 'Used to specify the path to a dependency file (e.g., go.mod, go.sum)'
   architecture:
     description: 'Target architecture for Go to use. Examples: x86, x64. Will use system architecture by default.'
+  go-download-base-url:
+    description: 'Custom base URL for downloading Go distributions. Use this to download Go from a mirror or custom source. Defaults to "https://go.dev/dl". Can also be set via the GO_DOWNLOAD_BASE_URL environment variable. The input takes precedence over the environment variable.'
 outputs:
   go-version:
     description: 'The installed Go version. Useful when given a version range as input.'
   cache-hit:
     description: 'A boolean value to indicate if a cache was hit'
 runs:
-  using: 'node20'
+  using: 'node24'
   main: 'dist/setup/index.js'
   post: 'dist/cache-save/index.js'
   post-if: success()

docs/advanced-usage.md

@@ -0,0 +1,498 @@
+# Advanced Usage
+- [Using the go-version input](advanced-usage.md#using-the-go-version-input)
+  - [Specifying a go version](advanced-usage.md#specifying-a-go-version)
+  - [Matrix testing](advanced-usage.md#matrix-testing)
+- [Using the go-version-file input](advanced-usage.md#using-the-go-version-file-input)
+- [Check latest version](advanced-usage.md#check-latest-version)
+- [Caching](advanced-usage.md#caching)
+  - [Caching in monorepos](advanced-usage.md#caching-in-monorepos)
+  - [Caching in multi-module repositories](advanced-usage.md#caching-in-multi-module-repositories)
+  - [Multi-target builds](advanced-usage.md#multi-target-builds)
+  - [Cache invalidation on source changes](advanced-usage.md#cache-invalidation-on-source-changes)
+  - [Restore-only caches](advanced-usage.md#restore-only-caches)
+  - [Parallel builds](advanced-usage.md#parallel-builds)
+- [Outputs](advanced-usage.md#outputs)
+- [Custom download URL](advanced-usage.md#custom-download-url)
+- [Using `setup-go` on GHES](advanced-usage.md#using-setup-go-on-ghes)
+
+## Using the `go-version` input
+
+### Specifying a Go version
+
+For repeatable builds, specify the **exact major, minor, and patch version** (such as `1.25.5`):
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25.5'
+  - run: go run hello.go
+```
+
+- The only downside is that setup may take a little longer. If the exact version is not already installed on the runner due to more recent versions, the exact version will have to be downloaded.
+
+You can specify **only a major and minor version** if you are okay with the most recent patch version being used:
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25'
+  - run: go run hello.go
+```
+
+- There will be a single patch version already installed on each runner for every minor version of Go that is supported.
+- The preinstalled patch version is generally the latest available. When a new patch is released, it replaces the previously preinstalled version on the runner.
+- Using the most recent patch version speeds up setup because the required Go version is already installed on the runner and no download is needed.
+
+To try a **pre-release**:
+Download and use beta or RC Go versions as needed.
+
+```yaml
+# RC version
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25.0-rc.2'
+  - run: go version
+```
+
+```yaml
+# Beta version
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.19.0-beta.1'
+  - run: go version
+```
+
+Using **stable/oldstable aliases**:
+
+If `stable` is provided, the action will get the latest stable version from the [`go-versions`](https://github.com/actions/go-versions/blob/main/versions-manifest.json) repository manifest.
+
+If `oldstable` is provided, the action resolves it to the latest patch release of the previous stable Go minor version (for example, if the latest stable is `1.25.x`, `oldstable` resolves to `1.24.x`, where `x` is the latest patch release).
+
+**Note:** Using these aliases will result in the same version as when using the corresponding minor release with the `check-latest` input set to `true`.  
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: 'stable'
+  - run: go run hello.go
+```
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: 'oldstable'
+  - run: go run hello.go
+```
+
+You can also use **SemVer's version range syntax**, for instance:
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '^1.25.1'
+  - run: go version
+```
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '>=1.24.0-rc.1'
+  - run: go version
+```
+
+### Matrix testing
+
+Using `setup-go` it's possible to use the [matrix syntax](https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstrategymatrix) to install several versions of Go:
+
+```yaml
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        go: [ '1.24', '1.25' ]
+    name: Go ${{ matrix.go }} sample
+    steps:
+      - uses: actions/checkout@v6
+      - name: Setup go
+        uses: actions/setup-go@v6
+        with:
+          go-version: ${{ matrix.go }}
+      - run: go run hello.go
+```
+
+Exclude a specific Go version:
+
+```yaml
+jobs:
+  build:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        go: [ '1.22', '1.24', '1.25']
+        exclude:
+          - os: macos-latest
+            go: '1.22'
+          - os: windows-latest
+            go: '1.25'
+    steps:
+      - uses: actions/checkout@v6
+      - name: Setup go
+        uses: actions/setup-go@v6
+        with:
+          go-version: ${{ matrix.go }}
+      - run: go run hello.go
+```
+
+## Using the `go-version-file` input
+
+`setup-go` action can read the Go version from a version file. `go-version-file` input is used for specifying the path to the version file. If the file supplied to the `go-version-file` input doesn't exist, the action will fail with an error. This input supports go.mod, go.work, .go-version, and .tool-versions files.
+
+If both the `go-version` and the `go-version-file` inputs are provided then the `go-version` input is used. The `.tool-versions` file supports version specifications in accordance with asdf standards, adhering to Semantic Versioning ([semver](https://semver.org)).
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version-file: 'path/to/go.mod'  # Read Go version from go.mod
+  - run: go version
+```
+
+- Uses the `toolchain` directive if present, otherwise the action falls back to the `go` directive.
+
+- The `go` directive in `go.mod` can specify a patch version or omit it altogether (e.g., `go 1.25.0` or `go 1.25`). If a patch version is specified, that specific patch version will be used. If no patch version is specified, it will search for the latest available patch version in the cache,
+[versions-manifest.json](https://github.com/actions/go-versions/blob/main/versions-manifest.json), and the
+[official Go language website](https://go.dev/dl/?mode=json&include=all), in that order.
+
+> The action will search for the `go.mod` file relative to the repository root.
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version-file: '.go-version' # Read Go version from .go-version
+  - run: go version
+```
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version-file: '.tool-versions' # Read Go version from .tool-versions
+  - run: go version
+```
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version-file: 'go.work' # Read Go version from go.work
+  - run: go version
+```
+
+## Check latest version
+
+The `check-latest` flag defaults to `false`. Use the default or set `check-latest` to `false` if you prefer stability
+and if you want to ensure a specific Go version is always used.
+
+If `check-latest` is set to `true`, the action first checks if the cached version is the latest one. If the locally
+cached version is not the most up-to-date, a Go version will then be downloaded. Set `check-latest` to `true` if you
+want the most up-to-date Go version to always be used. It supports major (e.g., "1") and major.minor (e.g., "1.25") version selectors, always resolving to the latest matching patch release.
+
+> Setting `check-latest` to `true` has performance implications as downloading Go versions is slower than using cached
+> versions.
+>
+> `check-latest` is ignored when `go-download-base-url` is set. See [Custom download URL](#custom-download-url) for details.
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25'
+      check-latest: true
+  - run: go run hello.go
+```
+
+## Caching
+ 
+### Caching in monorepos
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25'
+      cache-dependency-path: subdir/go.sum
+  - run: go run hello.go
+```
+
+### Caching in multi-module repositories
+
+`cache-dependency-path` input accepts glob patterns and multi-line values:
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25'
+      cache-dependency-path: '**/go.sum'
+  - run: go run hello.go
+```
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25'
+      cache-dependency-path: |
+        subdir/go.sum
+        tools/go.sum
+  - run: go run hello.go
+```
+
+### Multi-target builds
+
+`cache-dependency-path` isn’t limited to dependency files (like `go.sum`). It can also include files that capture build settings (for example, `GOOS`/`GOARCH`). This allows separate caches per target platform (OS/architecture) and helps avoid reusing caches across incompatible builds.
+
+```yaml
+env:
+  GOOS: ...
+  GOARCH: ...
+
+steps:
+  - run: echo "$GOOS $GOARCH" > env.txt
+
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25'
+      cache-dependency-path: |
+        go.sum
+        env.txt
+  - run: go run hello.go    
+```
+
+### Cache invalidation on source changes
+
+Besides dependencies, the action can also cache build outputs (the [`GOCACHE`](https://pkg.go.dev/cmd/go#hdr-Build_and_test_caching) directory). By default, this cache is not updated based on source changes to help avoid unpredictable and frequent cache invalidation. To invalidate the cache when source files change, include source files in the `cache-dependency-path` input.
+
+> **Note:** Including patterns like `**/*.go` can create new caches on many commits, increasing cache storage and potentially slowing workflows due to more frequent uploads/downloads.
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25'
+      cache-dependency-path: |
+        go.sum
+        **/*.go
+  - run: go run hello.go
+```
+
+### Restore-only caches
+
+Restore caches without saving new entries. This can help reduce cache writes and storage usage in workflows that only need to read from the cache:
+
+```yaml
+jobs:
+  build:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+    steps:
+      - uses: actions/checkout@v6
+      - name: Setup go
+        id: setup-go
+        uses: actions/setup-go@v6
+        with:
+          go-version: '1.25.5'
+          cache: false
+      # Capture Go cache locations
+      - name: Set Go cache variables (Linux/macOS)
+        if: runner.os != 'Windows'
+        run: |
+          echo "GO_MOD_CACHE=$(go env GOMODCACHE)" >> $GITHUB_ENV
+          echo "GO_BUILD_CACHE=$(go env GOCACHE)" >> $GITHUB_ENV
+      - name: Set Go cache variables (Windows)
+        if: runner.os == 'Windows'
+        shell: pwsh
+        run: |
+          echo "GO_MOD_CACHE=$(go env GOMODCACHE)" | Out-File $env:GITHUB_ENV -Append
+          echo "GO_BUILD_CACHE=$(go env GOCACHE)"   | Out-File $env:GITHUB_ENV -Append
+      # Normalize runner.arch to lowercase to ensure consistent cache keys
+      - name: Normalize runner architecture (Linux/macOS)
+        if: runner.os != 'Windows'
+        shell: bash
+        run: echo "ARCH=$(echo '${{ runner.arch }}' | tr '[:upper:]' '[:lower:]')" >> $GITHUB_ENV
+      - name: Normalize runner architecture (Windows)
+        if: runner.os == 'Windows'
+        shell: pwsh
+        run: |
+          $arch = "${{ runner.arch }}".ToLower()
+          echo "ARCH=$arch" | Out-File $env:GITHUB_ENV -Append
+      - name: Set cache OS suffix for Linux
+        if: runner.os == 'Linux'
+        shell: bash
+        run: echo "CACHE_OS_SUFFIX=$ImageOS-" >> $GITHUB_ENV
+      - name: Restore Go cache
+        id: go-cache
+        uses: actions/cache/restore@v5
+        with:
+          path: |
+            ${{ env.GO_MOD_CACHE }}
+            ${{ env.GO_BUILD_CACHE }}
+          key: setup-go-${{ runner.os }}-${{ env.ARCH }}-${{ env.CACHE_OS_SUFFIX }}go-${{ steps.setup-go.outputs.go-version }}-${{ hashFiles('**/go.mod') }}
+      - name: Download modules
+        run: go mod download
+      - name: Build
+        run: go build ./...
+```
+
+> If there are several builds on the same repo, it may make sense to create a cache in one build and use it in others. The action [actions/cache/restore](https://github.com/actions/cache/tree/main/restore#only-restore-cache)
+should be used in this case.
+
+### Parallel builds
+
+To avoid race conditions during parallel builds, either use distinct cache keys with [actions/cache](https://github.com/actions/cache/blob/main/examples.md#go---modules), or create the cache in only one build and [restore](#restore-only-caches) it in the other builds.
+
+## Outputs
+
+### `go-version`
+
+Using **go-version** output, it's possible to get the precise Go version installed by the action. This output is useful when the input `go-version` is given as a range, but down the line you need to operate (such as in an `if:` statement) with the exact installed version (e.g. 1.24.11). 
+
+```yaml
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+      - uses: actions/setup-go@v6
+        id: go124
+        with:
+          go-version: '^1.24'
+      - run: echo "Installed Go version: ${{ steps.go124.outputs.go-version }}"
+```
+
+### `cache-hit`
+
+**cache-hit** output is available with a boolean value that indicates whether a cache hit occurred on the primary key:
+
+```yaml
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+      - uses: actions/setup-go@v6
+        id: go124
+        with:
+          go-version: '1.24'
+          cache: true
+      - run: echo "Was the Go cache restored? ${{ steps.go124.outputs.cache-hit }}" # true if cache-hit occurred
+```
+
+## Custom download URL
+
+The `go-download-base-url` input lets you download Go from a mirror or alternative source instead of the default `https://go.dev/dl`. This can also be set via the `GO_DOWNLOAD_BASE_URL` environment variable; the input takes precedence over the environment variable.
+
+When a custom base URL is provided, the action skips the `actions/go-versions` manifest lookup and downloads directly from the specified URL.
+
+**Using the [Microsoft build of Go](https://github.com/microsoft/go):**
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25'
+      go-download-base-url: 'https://aka.ms/golang/release/latest'
+  - run: go version
+```
+
+**Using an environment variable:**
+
+```yaml
+env:
+  GO_DOWNLOAD_BASE_URL: 'https://aka.ms/golang/release/latest'
+
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25'
+  - run: go version
+```
+
+> **Note:** Version range syntax (`^1.25`, `~1.24`, `>=1.25.0`) and aliases (`stable`, `oldstable`) are not supported with custom download URLs. Use exact versions such as `1.25`, `1.25.0`, or `1.25.0-1` (for sources that use revision numbers). If the custom server provides a version listing endpoint (`/?mode=json&include=all`), semver ranges will work; otherwise only exact versions are accepted.
+
+> **Note:** The `check-latest` option is ignored when a custom download base URL is set. The action cannot query the custom server for the latest version, so it uses the version you specify directly. If you provide a partial version like `1.25`, the server determines which patch release to serve.
+
+**Authenticated downloads:**
+
+If your custom download source requires authentication, the `token` input is forwarded as an `Authorization` header. For example, to download from a private mirror:
+
+```yaml
+steps:
+  - uses: actions/checkout@v6
+  - uses: actions/setup-go@v6
+    with:
+      go-version: '1.25'
+      go-download-base-url: 'https://private-mirror.example.com/golang'
+      token: ${{ secrets.MIRROR_TOKEN }}
+  - run: go version
+```
+
+## Using `setup-go` on GHES
+
+### Avoiding rate limit issues
+
+`setup-go` comes pre-installed on the appliance with GHES if Actions is enabled.
+When dynamically downloading Go distributions, `setup-go` downloads distributions from [`actions/go-versions`](https://github.com/actions/go-versions) on github.com (outside of the appliance).
+
+These calls to `actions/go-versions` are made via unauthenticated requests, which are limited to [60 requests per hour per IP](https://docs.github.com/en/rest/overview/resources-in-the-rest-api#rate-limiting).
+If more requests are made within the time frame, then the action leverages the `raw API` to retrieve the version-manifest. This approach does not impose a rate limit and hence facilitates unrestricted consumption. This is particularly beneficial for GHES runners, which often share the same IP, to avoid the quick exhaustion of the unauthenticated rate limit.
+If that fails as well the action will try to download versions directly from [go.dev](https://go.dev/dl).
+
+If that fails as well you can get a higher rate limit with [generating a personal access token on github.com](https://github.com/settings/tokens/new) and passing it as the `token` input to the action:
+
+```yaml
+uses: actions/setup-go@v6
+with:
+  token: ${{ secrets.GH_DOTCOM_TOKEN }}
+  go-version: '1.25'
+```
+
+### No access to github.com
+
+If the runner is not able to access github.com, any Go versions requested during a workflow run must come from the runner's tool cache.
+See "[Setting up the tool cache on self-hosted runners without internet access](https://docs.github.com/en/enterprise-server@3.2/admin/github-actions/managing-access-to-actions-from-githubcom/setting-up-the-tool-cache-on-self-hosted-runners-without-internet-access)"
+for more information.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "setup-go",
-  "version": "6.0.0",
+  "version": "6.5.0",
   "private": true,
   "description": "setup go action",
   "main": "lib/setup-go.js",
@@ -28,24 +28,24 @@
   "author": "GitHub",
   "license": "MIT",
   "dependencies": {
-    "@actions/cache": "^4.0.3",
+    "@actions/cache": "^5.1.0",
-    "@actions/core": "^1.11.1",
+    "@actions/core": "^2.0.3",
-    "@actions/exec": "^1.1.1",
+    "@actions/exec": "^2.0.0",
-    "@actions/glob": "^0.5.0",
+    "@actions/glob": "^0.5.1",
-    "@actions/http-client": "^2.2.1",
+    "@actions/http-client": "^3.0.2",
-    "@actions/io": "^1.0.2",
+    "@actions/io": "^2.0.0",
-    "@actions/tool-cache": "^2.0.2",
+    "@actions/tool-cache": "^3.0.1",
-    "semver": "^7.6.3"
+    "semver": "^7.7.3"
   },
   "devDependencies": {
     "@types/jest": "^29.5.14",
-    "@types/node": "^24.1.0",
+    "@types/node": "^25.9.3",
-    "@types/semver": "^7.5.8",
+    "@types/semver": "^7.7.1",
-    "@typescript-eslint/eslint-plugin": "^8.31.1",
+    "@typescript-eslint/eslint-plugin": "^8.61.0",
-    "@typescript-eslint/parser": "^8.35.1",
+    "@typescript-eslint/parser": "^8.61.0",
     "@vercel/ncc": "^0.38.1",
     "eslint": "^8.57.0",
-    "eslint-config-prettier": "^10.0.1",
+    "eslint-config-prettier": "^10.1.8",
     "eslint-plugin-jest": "^29.0.1",
     "eslint-plugin-node": "^11.1.0",
     "jest": "^29.7.0",

src/cache-restore.ts

@@ -55,8 +55,8 @@ const findDependencyFile = (packageManager: PackageManagerInfo) => {
   const workspace = process.env.GITHUB_WORKSPACE!;
   const rootContent = fs.readdirSync(workspace);
 
-  const goSumFileExists = rootContent.includes(dependencyFile);
+  const goModFileExists = rootContent.includes(dependencyFile);
-  if (!goSumFileExists) {
+  if (!goModFileExists) {
     throw new Error(
       `Dependencies file is not found in ${workspace}. Supported file pattern: ${dependencyFile}`
     );

src/cache-save.ts

@@ -15,6 +15,7 @@ process.on('uncaughtException', e => {
 // Added early exit to resolve issue with slow post action step:
 // - https://github.com/actions/setup-node/issues/878
 // https://github.com/actions/cache/pull/1217
+
 export async function run(earlyExit?: boolean) {
   try {
     const cacheInput = core.getBooleanInput('cache');
@@ -80,6 +81,10 @@ const cachePackages = async () => {
 
   const cacheId = await cache.saveCache(cachePaths, primaryKey);
   if (cacheId === -1) {
+    // saveCache returns -1 without throwing when the cache was not saved, e.g.
+    // a reserve collision or a read-only token (fork PR). @actions/cache has
+    // already logged the reason at the appropriate severity, so just trace it.
+    core.debug(`Cache was not saved for the key: ${primaryKey}`);
     return;
   }
   core.info(`Cache saved with the key: ${primaryKey}`);

src/installer.ts

@@ -4,6 +4,8 @@ import * as path from 'path';
 import * as semver from 'semver';
 import * as httpm from '@actions/http-client';
 import * as sys from './system';
+import crypto from 'crypto';
+import cp from 'child_process';
 import fs from 'fs';
 import os from 'os';
 import {StableReleaseAlias, isSelfHosted} from './utils';
@@ -15,9 +17,17 @@ const MANIFEST_REPO_OWNER = 'actions';
 const MANIFEST_REPO_NAME = 'go-versions';
 const MANIFEST_REPO_BRANCH = 'main';
 const MANIFEST_URL = `https://raw.githubusercontent.com/${MANIFEST_REPO_OWNER}/${MANIFEST_REPO_NAME}/${MANIFEST_REPO_BRANCH}/versions-manifest.json`;
+const DEFAULT_GO_DOWNLOAD_BASE_URL = 'https://go.dev/dl';
 
 type InstallationType = 'dist' | 'manifest';
 
+const GOLANG_DOWNLOAD_URL = 'https://go.dev/dl/?mode=json&include=all';
+
+// Base URLs known to not serve a version listing JSON endpoint.
+// For these URLs we skip the getInfoFromDist() call entirely and construct
+// the download URL directly, avoiding a guaranteed-404 HTTP request.
+const NO_VERSION_LISTING_BASE_URLS = ['https://aka.ms/golang/release/latest'];
+
 export interface IGoVersionFile {
   filename: string;
   // darwin, linux, windows
@@ -42,15 +52,23 @@ export async function getGo(
   versionSpec: string,
   checkLatest: boolean,
   auth: string | undefined,
-  arch: Architecture = os.arch() as Architecture
+  arch: Architecture = os.arch() as Architecture,
+  goDownloadBaseUrl?: string
 ) {
   let manifest: tc.IToolRelease[] | undefined;
   const osPlat: string = os.platform();
+  const customBaseUrl = goDownloadBaseUrl?.replace(/\/+$/, '');
 
   if (
     versionSpec === StableReleaseAlias.Stable ||
     versionSpec === StableReleaseAlias.OldStable
   ) {
+    if (customBaseUrl) {
+      throw new Error(
+        `Version aliases '${versionSpec}' are not supported with a custom download base URL. Please specify an exact Go version.`
+      );
+    }
+
     manifest = await getManifest(auth);
     let stableVersion = await resolveStableVersionInput(
       versionSpec,
@@ -74,7 +92,14 @@ export async function getGo(
   }
 
   if (checkLatest) {
-    core.info('Attempting to resolve the latest version from the manifest...');
+    if (customBaseUrl) {
+      core.info(
+        'check-latest is not supported with a custom download base URL. Using the provided version spec directly.'
+      );
+    } else {
+      core.info(
+        'Attempting to resolve the latest version from the manifest...'
+      );
       const resolvedVersion = await resolveVersionFromManifest(
         versionSpec,
         true,
@@ -89,9 +114,16 @@ export async function getGo(
         core.info(`Failed to resolve version ${versionSpec} from manifest`);
       }
     }
+  }
+
+  // Use a distinct tool cache name for custom downloads to avoid
+  // colliding with the runner's pre-installed Go
+  const toolCacheName = customBaseUrl
+    ? customToolCacheName(customBaseUrl)
+    : 'go';
 
   // check cache
-  const toolPath = tc.find('go', versionSpec, arch);
+  const toolPath = tc.find(toolCacheName, versionSpec, arch);
   // If not found in cache, download
   if (toolPath) {
     core.info(`Found in cache @ ${toolPath}`);
@@ -101,6 +133,49 @@ export async function getGo(
   let downloadPath = '';
   let info: IGoVersionInfo | null = null;
 
+  if (customBaseUrl) {
+    //
+    // Download from custom base URL
+    //
+    const skipVersionListing = NO_VERSION_LISTING_BASE_URLS.some(
+      url => customBaseUrl.toLowerCase() === url.toLowerCase()
+    );
+
+    if (skipVersionListing) {
+      core.info(
+        'Skipping version listing for known direct-download URL. Constructing download URL directly.'
+      );
+      info = getInfoFromDirectDownload(versionSpec, arch, customBaseUrl);
+    } else {
+      try {
+        info = await getInfoFromDist(versionSpec, arch, customBaseUrl);
+      } catch {
+        core.info(
+          'Version listing not available from custom URL. Constructing download URL directly.'
+        );
+      }
+      if (!info) {
+        info = getInfoFromDirectDownload(versionSpec, arch, customBaseUrl);
+      }
+    }
+
+    try {
+      core.info('Install from custom download URL');
+      downloadPath = await installGoVersion(info, auth, arch, toolCacheName);
+    } catch (err) {
+      const downloadUrl = info?.downloadUrl || customBaseUrl;
+      if (err instanceof tc.HTTPError && err.httpStatusCode === 404) {
+        throw new Error(
+          `The requested Go version ${versionSpec} is not available for platform ${osPlat}/${arch}. ` +
+            `Download URL returned HTTP 404: ${downloadUrl}`
+        );
+      }
+      throw new Error(
+        `Failed to download Go ${versionSpec} for platform ${osPlat}/${arch} ` +
+          `from ${downloadUrl}: ${err}`
+      );
+    }
+  } else {
     //
     // Try download from internal distribution (popular versions only)
     //
@@ -146,6 +221,7 @@ export async function getGo(
         throw new Error(`Failed to download version ${versionSpec}: ${err}`);
       }
     }
+  }
 
   return downloadPath;
 }
@@ -227,20 +303,26 @@ async function cacheWindowsDir(
 async function addExecutablesToToolCache(
   extPath: string,
   info: IGoVersionInfo,
-  arch: string
+  arch: string,
+  toolName: string = 'go'
 ): Promise<string> {
-  const tool = 'go';
   const version = makeSemver(info.resolvedVersion);
   return (
-    (await cacheWindowsDir(extPath, tool, version, arch)) ||
+    (await cacheWindowsDir(extPath, toolName, version, arch)) ||
-    (await tc.cacheDir(extPath, tool, version, arch))
+    (await tc.cacheDir(extPath, toolName, version, arch))
   );
 }
 
+export function customToolCacheName(baseUrl: string): string {
+  const hash = crypto.createHash('sha256').update(baseUrl).digest('hex');
+  return `go-${hash.substring(0, 8)}`;
+}
+
 async function installGoVersion(
   info: IGoVersionInfo,
   auth: string | undefined,
-  arch: string
+  arch: string,
+  toolName: string = 'go'
 ): Promise<string> {
   core.info(`Acquiring ${info.resolvedVersion} from ${info.downloadUrl}`);
 
@@ -258,13 +340,48 @@ async function installGoVersion(
     extPath = path.join(extPath, 'go');
   }
 
+  // For custom downloads, detect the actual installed version so the cache
+  // key reflects the real patch level (e.g. input "1.20" may install 1.20.14).
+  if (toolName !== 'go') {
+    const actualVersion = detectInstalledGoVersion(extPath);
+    if (actualVersion && actualVersion !== info.resolvedVersion) {
+      core.info(
+        `Requested version '${info.resolvedVersion}' resolved to installed version '${actualVersion}'`
+      );
+      info.resolvedVersion = actualVersion;
+    }
+  }
+
   core.info('Adding to the cache ...');
-  const toolCacheDir = await addExecutablesToToolCache(extPath, info, arch);
+  const toolCacheDir = await addExecutablesToToolCache(
+    extPath,
+    info,
+    arch,
+    toolName
+  );
   core.info(`Successfully cached go to ${toolCacheDir}`);
 
   return toolCacheDir;
 }
 
+function detectInstalledGoVersion(goDir: string): string | null {
+  try {
+    const goBin = path.join(
+      goDir,
+      'bin',
+      os.platform() === 'win32' ? 'go.exe' : 'go'
+    );
+    const output = cp.execFileSync(goBin, ['version'], {encoding: 'utf8'});
+    const match = output.match(/go version go(\S+)/);
+    return match ? match[1] : null;
+  } catch (err) {
+    core.debug(
+      `Failed to detect installed Go version: ${(err as Error).message}`
+    );
+    return null;
+  }
+}
+
 export async function extractGoArchive(archivePath: string): Promise<string> {
   const platform = os.platform();
   let extPath: string;
@@ -382,14 +499,23 @@ export async function getInfoFromManifest(
 
 async function getInfoFromDist(
   versionSpec: string,
-  arch: Architecture
+  arch: Architecture,
+  goDownloadBaseUrl?: string
 ): Promise<IGoVersionInfo | null> {
-  const version: IGoVersion | undefined = await findMatch(versionSpec, arch);
+  const dlUrl = goDownloadBaseUrl
+    ? `${goDownloadBaseUrl}/?mode=json&include=all`
+    : GOLANG_DOWNLOAD_URL;
+  const version: IGoVersion | undefined = await findMatch(
+    versionSpec,
+    arch,
+    dlUrl
+  );
   if (!version) {
     return null;
   }
 
-  const downloadUrl = `https://storage.googleapis.com/golang/${version.files[0].filename}`;
+  const baseUrl = goDownloadBaseUrl || DEFAULT_GO_DOWNLOAD_BASE_URL;
+  const downloadUrl = `${baseUrl}/${version.files[0].filename}`;
 
   return <IGoVersionInfo>{
     type: 'dist',
@@ -399,9 +525,43 @@ async function getInfoFromDist(
   };
 }
 
+export function getInfoFromDirectDownload(
+  versionSpec: string,
+  arch: Architecture,
+  goDownloadBaseUrl: string
+): IGoVersionInfo {
+  // Reject version specs that can't map to an artifact filename
+  if (/[~^>=<|*x]/.test(versionSpec)) {
+    throw new Error(
+      `Version range '${versionSpec}' is not supported with a custom download base URL ` +
+        `when version listing is unavailable. Please specify an exact version (e.g., '1.25.0').`
+    );
+  }
+
+  const archStr = sys.getArch(arch);
+  const platStr = sys.getPlatform();
+  const extension = platStr === 'windows' ? 'zip' : 'tar.gz';
+  // Ensure version has the 'go' prefix for the filename
+  const goVersion = versionSpec.startsWith('go')
+    ? versionSpec
+    : `go${versionSpec}`;
+  const fileName = `${goVersion}.${platStr}-${archStr}.${extension}`;
+  const downloadUrl = `${goDownloadBaseUrl}/${fileName}`;
+
+  core.info(`Constructed direct download URL: ${downloadUrl}`);
+
+  return <IGoVersionInfo>{
+    type: 'dist',
+    downloadUrl: downloadUrl,
+    resolvedVersion: versionSpec.replace(/^go/, ''),
+    fileName: fileName
+  };
+}
+
 export async function findMatch(
   versionSpec: string,
-  arch: Architecture = os.arch() as Architecture
+  arch: Architecture = os.arch() as Architecture,
+  dlUrl: string = GOLANG_DOWNLOAD_URL
 ): Promise<IGoVersion | undefined> {
   const archFilter = sys.getArch(arch);
   const platFilter = sys.getPlatform();
@@ -409,7 +569,6 @@ export async function findMatch(
   let result: IGoVersion | undefined;
   let match: IGoVersion | undefined;
 
-  const dlUrl = 'https://golang.org/dl/?mode=json&include=all';
   const candidates: IGoVersion[] | null = await module.exports.getVersionsDist(
     dlUrl
   );
@@ -513,6 +672,9 @@ export function parseGoVersionFile(versionFilePath: string): string {
     // go directive: https://go.dev/ref/mod#go-mod-file-go
     const matchGo = contents.match(/^go (\d+(\.\d+)*)/m);
     return matchGo ? matchGo[1] : '';
+  } else if (path.basename(versionFilePath) === '.tool-versions') {
+    const match = contents.match(/^golang\s+([^\n#]+)/m);
+    return match ? match[1].trim() : '';
   }
 
   return contents.trim();
@@ -524,9 +686,8 @@ async function resolveStableVersionDist(
 ) {
   const archFilter = sys.getArch(arch);
   const platFilter = sys.getPlatform();
-  const dlUrl = 'https://golang.org/dl/?mode=json&include=all';
   const candidates: IGoVersion[] | null = await module.exports.getVersionsDist(
-    dlUrl
+    GOLANG_DOWNLOAD_URL
   );
   if (!candidates) {
     throw new Error(`golang download url did not return results`);

src/main.ts

@@ -34,11 +34,21 @@ export async function run() {
 
       const checkLatest = core.getBooleanInput('check-latest');
 
+      const goDownloadBaseUrl =
+        core.getInput('go-download-base-url') ||
+        process.env['GO_DOWNLOAD_BASE_URL'] ||
+        undefined;
+
+      if (goDownloadBaseUrl) {
+        core.info(`Using custom Go download base URL: ${goDownloadBaseUrl}`);
+      }
+
       const installDir = await installer.getGo(
         versionSpec,
         checkLatest,
         auth,
-        arch
+        arch,
+        goDownloadBaseUrl
       );
 
       const installDirVersion = path.basename(path.dirname(installDir));

src/package-managers.ts

@@ -9,7 +9,7 @@ export interface PackageManagerInfo {
 
 export const supportedPackageManagers: SupportedPackageManagers = {
   default: {
-    dependencyFilePattern: 'go.sum',
+    dependencyFilePattern: 'go.mod',
     cacheFolderCommandList: ['go env GOMODCACHE', 'go env GOCACHE']
   }
 };