Fix for #2677 (#2705)

* Update docs given https://github.com/yaml/go-yaml/pull/348

* Fix for https://github.com/mikefarah/yq/issues/2677

Depends on https://github.com/yaml/go-yaml/pull/348

* Test for https://github.com/mikefarah/yq/issues/2677

* Remove redundant check and add test case for explicit `!!merge` on `*+` traversal

* Bump go.yaml.in/yaml/v4 from 4.0.0-rc.4 to 4.0.0-rc.5

go.mod

@@ -19,7 +19,7 @@ require (
 	github.com/spf13/pflag v1.0.10
 	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
+	go.yaml.in/yaml/v4 v4.0.0-rc.5
 	golang.org/x/mod v0.36.0
 	golang.org/x/net v0.55.0
 	golang.org/x/text v0.37.0

go.sum

@@ -68,8 +68,8 @@ github.com/zclconf/go-cty v1.18.1/go.mod h1:qpnV6EDNgC1sns/AleL1fvatHw72j+S+nS+M
 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.4 h1:UP4+v6fFrBIb1l934bDl//mmnoIZEDK0idg1+AIvX5U=
+go.yaml.in/yaml/v4 v4.0.0-rc.5 h1:JVliQq9EGOYaTgMi+k8BhUJyqcGk4ZqeuiN1Cirba9c=
-go.yaml.in/yaml/v4 v4.0.0-rc.4/go.mod h1:aZqd9kCMsGL7AuUv/m/PvWLdg5sjJsZ4oHDEnfPPfY0=
+go.yaml.in/yaml/v4 v4.0.0-rc.5/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 v0.55.0 h1:bcvxaJn3e1U6InsFWt1JUq1aSjnRxLzT2rtD2KfkDF8=

pkg/yqlib/candidate_node.go

@@ -46,7 +46,11 @@ const (
 func createStringScalarNode(stringValue string) *CandidateNode {
 	var node = &CandidateNode{Kind: ScalarNode}
 	node.Value = stringValue
-	node.Tag = "!!str"
+	if stringValue == "<<" {
+		node.Tag = "!!merge"
+	} else {
+		node.Tag = "!!str"
+	}
 	return node
 }
 

pkg/yqlib/doc/operators/anchor-and-alias-operators.md

@@ -32,7 +32,7 @@ Given a sample.yml file of:
   r: 10
 - &SMALL
   r: 1
-- !!merge <<: *CENTRE
+- <<: *CENTRE
   r: 10
 ```
 then
@@ -213,10 +213,10 @@ item_value: &item_value
   value: true
 thingOne:
   name: item_1
-  !!merge <<: *item_value
+  <<: *item_value
 thingTwo:
   name: item_2
-  !!merge <<: *item_value
+  <<: *item_value
 ```
 then
 ```bash
@@ -231,7 +231,7 @@ thingOne:
   value: false
 thingTwo:
   name: item_2
-  !!merge <<: *item_value
+  <<: *item_value
 ```
 
 ## LEGACY: Explode with merge anchors
@@ -249,13 +249,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -298,7 +298,7 @@ Given a sample.yml file of:
   r: 10
 - &SMALL
   r: 1
-- !!merge <<:
+- <<:
     - *CENTRE
     - *BIG
 ```
@@ -328,7 +328,7 @@ Given a sample.yml file of:
   r: 10
 - &SMALL
   r: 1
-- !!merge <<:
+- <<:
     - *BIG
     - *LEFT
     - *SMALL
@@ -361,13 +361,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -411,7 +411,7 @@ Given a sample.yml file of:
   r: 10
 - &SMALL
   r: 1
-- !!merge <<:
+- <<:
     - *CENTRE
     - *BIG
 ```
@@ -442,7 +442,7 @@ Given a sample.yml file of:
   r: 10
 - &SMALL
   r: 1
-- !!merge <<:
+- <<:
     - *BIG
     - *LEFT
     - *SMALL
@@ -467,7 +467,7 @@ Given a sample.yml file of:
 ```yaml
 a:
   b: &b 42
-!!merge <<:
+<<:
   c: *b
 ```
 then

pkg/yqlib/doc/operators/divide.md

@@ -55,7 +55,7 @@ yq '.a = .a / 0 | .b = .b / 0' sample.yml
 ```
 will output
 ```yaml
-a: !!float +Inf
+a: +Inf
-b: !!float -Inf
+b: -Inf
 ```
 

pkg/yqlib/doc/operators/modulo.md

@@ -34,7 +34,7 @@ yq '.a = .a % .b' sample.yml
 ```
 will output
 ```yaml
-a: !!float 2
+a: 2
 b: 2.5
 ```
 
@@ -69,7 +69,7 @@ yq '.a = .a % .b' sample.yml
 ```
 will output
 ```yaml
-a: !!float NaN
+a: NaN
 b: 0
 ```
 

pkg/yqlib/doc/operators/multiply-merge.md

@@ -471,13 +471,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -487,7 +487,7 @@ yq '.foobar * .foobarList' sample.yml
 will output
 ```yaml
 c: foobarList_c
-!!merge <<:
+<<:
   - *foo
   - *bar
 thing: foobar_thing

pkg/yqlib/doc/operators/recursive-descent-glob.md

@@ -131,13 +131,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -147,7 +147,7 @@ yq '.foobar | [..]' sample.yml
 will output
 ```yaml
 - c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 - foobar_c
 - *foo

pkg/yqlib/doc/operators/traverse-read.md

@@ -294,13 +294,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -325,13 +325,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -376,13 +376,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -409,13 +409,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -442,13 +442,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -477,13 +477,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -513,13 +513,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -546,13 +546,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -579,13 +579,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then
@@ -614,13 +614,13 @@ bar: &bar
   c: bar_c
 foobarList:
   b: foobarList_b
-  !!merge <<:
+  <<:
     - *foo
     - *bar
   c: foobarList_c
 foobar:
   c: foobar_c
-  !!merge <<: *foo
+  <<: *foo
   thing: foobar_thing
 ```
 then

pkg/yqlib/goccy_yaml_test.go

@@ -230,8 +230,7 @@ var goccyYamlFormatScenarios = []formatScenario{
 		description: "merge anchor",
 		skipDoc:     true,
 		input:       "a: &remember\n  c: mike\nb:\n  <<: *remember",
-		// fine to have !!merge as that's what the current impl does
+		expected: "a: &remember\n  c: mike\nb:\n  <<: *remember\n",
-		expected: "a: &remember\n  c: mike\nb:\n  !!merge <<: *remember\n",
 	},
 	{
 		description: "custom tag",

pkg/yqlib/lib_test.go

@@ -24,7 +24,7 @@ type parseSnippetScenario struct {
 var parseSnippetScenarios = []parseSnippetScenario{
 	{
 		snippet:       ":",
-		expectedError: "yaml: while parsing a block mapping at <unknown position>: did not find expected key",
+		expectedError: "go-yaml load error in parser (while parsing a block mapping) at L1.C1: did not find expected key",
 	},
 	{
 		snippet: "",

pkg/yqlib/operator_anchors_aliases_test.go

@@ -31,7 +31,7 @@ thingOne:
     value: false
 thingTwo:
     name: item_2
-    !!merge <<: *item_value
+    <<: *item_value
 `
 
 var explodeMergeAnchorsFixedExpected = `D0, P[], (!!map)::foo:
@@ -288,7 +288,63 @@ var badAnchorOperatorScenarios = []expressionScenario{
 	},
 }
 
+var mixedMergeTagStyleDocument = `
+constants:
+    errorResponse: &errorResponse
+        status: 200
+endpoints:
+    - condition: true
+      !!merge <<: *errorResponse
+    - condition: false
+      <<: *errorResponse
+other:
+    !!merge <<: *errorResponse
+somethingElse:
+    <<: *errorResponse
+`
+
+var mixedMergeTagStyleExplodedDocument = `
+constants:
+    errorResponse:
+        status: 200
+endpoints:
+    - condition: true
+      status: 200
+    - condition: false
+      status: 200
+other:
+    status: 200
+somethingElse:
+    status: 200
+`
+
 var anchorOperatorScenarios = []expressionScenario{
+	{
+		// mergeObjects previously skipped all !!merge-tagged nodes. Since !!merge only appears on
+		// << map keys, this meant applyAssignment was never called for the << key. It was later
+		// autocreated by createStringScalarNode("<<") with tag !!str, silently dropping !!merge.
+		// DontFollowAlias:true already prevents aliases being followed, so the skip was redundant.
+		// Old (buggy) output: "D0, P[], (!!map)::base: &base\n    x: 1\ndest:\n    <<: *base\n"
+		skipDoc:     true,
+		description: "direct *+ preserves explicit !!merge tag on << key (regression for issue 2677)",
+		document:    "base: &base\n    x: 1\ndest:\n    !!merge <<: *base\n",
+		expression:  `. as $d | {} *+ $d`,
+		expected:    []string{"D0, P[], (!!map)::base: &base\n    x: 1\ndest:\n    !!merge <<: *base\n"},
+	},
+	{
+		skipDoc:     true,
+		description: "explicit !!merge tag on << key is preserved through ireduce merge",
+		document:    mixedMergeTagStyleDocument,
+		expression:  `. as $item ireduce ({}; . *+ $item)`,
+		expected:    []string{"D0, P[], (!!map)::" + mixedMergeTagStyleDocument},
+	},
+	{
+		skipDoc:     true,
+		description: "explode expands << merge keys regardless of explicit tag style (!!merge or plain)",
+		document:    mixedMergeTagStyleDocument,
+		expression:  `explode(.)`,
+		expected:    []string{"D0, P[], (!!map)::" + mixedMergeTagStyleExplodedDocument},
+	},
 	{
 		skipDoc:     true,
 		description: "merge anchor to alias alias",

pkg/yqlib/operator_divide_test.go

@@ -45,7 +45,7 @@ var divideOperatorScenarios = []expressionScenario{
 		document:       `{a: 1, b: -1}`,
 		expression:     `.a = .a / 0 | .b = .b / 0`,
 		expected: []string{
-			"D0, P[], (!!map)::{a: !!float +Inf, b: !!float -Inf}\n",
+			"D0, P[], (!!map)::{a: +Inf, b: -Inf}\n",
 		},
 	},
 	{

pkg/yqlib/operator_load_test.go

@@ -77,7 +77,7 @@ var loadScenarios = []expressionScenario{
 		document:       `{something: {file: "thing.yml"}, over: {here: [{file: "thing.yml"}]}}`,
 		expression:     `(.. | select(has("file"))) |= load("../../examples/" + .file)`,
 		expected: []string{
-			"D0, P[], (!!map)::{something: {a: apple is included, b: cool.}, over: {here: [{a: apple is included, b: cool.}]}}\n",
+			"D0, P[], (!!map)::{something: {a: apple is included, b: cool.}, over: {here: [{a: apple is included,\n                b: cool.}]}}\n",
 		},
 	},
 	{

pkg/yqlib/operator_modulo_test.go

@@ -37,7 +37,7 @@ var moduloOperatorScenarios = []expressionScenario{
 		document:       `{a: 12, b: 2.5}`,
 		expression:     `.a = .a % .b`,
 		expected: []string{
-			"D0, P[], (!!map)::{a: !!float 2, b: 2.5}\n",
+			"D0, P[], (!!map)::{a: 2, b: 2.5}\n",
 		},
 	},
 	{
@@ -53,7 +53,7 @@ var moduloOperatorScenarios = []expressionScenario{
 		document:       `{a: 1.1, b: 0}`,
 		expression:     `.a = .a % .b`,
 		expected: []string{
-			"D0, P[], (!!map)::{a: !!float NaN, b: 0}\n",
+			"D0, P[], (!!map)::{a: NaN, b: 0}\n",
 		},
 	},
 	{
@@ -70,7 +70,7 @@ var moduloOperatorScenarios = []expressionScenario{
 		document:   "a: 2\nb: !goat 2.3",
 		expression: `.a = .a % .b`,
 		expected: []string{
-			"D0, P[], (!!map)::a: !!float 2\nb: !goat 2.3\n",
+			"D0, P[], (!!map)::a: 2\nb: !goat 2.3\n",
 		},
 	},
 	{

pkg/yqlib/operator_multiply.go

@@ -189,10 +189,6 @@ func mergeObjects(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs
 
 		log.Debugf("going to applied assignment to LHS: %v with RHS: %v", NodeToString(lhs), NodeToString(candidate))
 
-		if candidate.Tag == "!!merge" {
-			continue
-		}
-
 		err := applyAssignment(d, context, pathIndexToStartFrom, lhs, candidate, preferences)
 		if err != nil {
 			return nil, err

pkg/yqlib/operator_multiply_test.go

@@ -121,7 +121,7 @@ var multiplyOperatorScenarios = []expressionScenario{
 		document:   mergeArrayWithAnchors,
 		expression: `. * .`,
 		expected: []string{
-			"D0, P[], (!!map)::sample:\n    - &a\n    - !!merge <<: *a\n",
+			"D0, P[], (!!map)::sample:\n    - &a\n    - <<: *a\n",
 		},
 	},
 	{
@@ -514,7 +514,7 @@ var multiplyOperatorScenarios = []expressionScenario{
 		environmentVariables: map[string]string{"originalPath": ".myArray", "otherPath": ".newArray", "idPath": ".a"},
 		expression:           mergeExpression,
 		expected: []string{
-			"D0, P[], (!!map)::{myArray: [{a: apple, b: appleB2}, {a: kiwi, b: kiwiB}, {a: banana, b: bananaB, c: bananaC}, {a: dingo, c: dingoC}], something: else}\n",
+			"D0, P[], (!!map)::{myArray: [{a: apple, b: appleB2}, {a: kiwi, b: kiwiB}, {a: banana, b: bananaB, c: bananaC},\n        {a: dingo, c: dingoC}], something: else}\n",
 		},
 	},
 	{
@@ -546,7 +546,7 @@ var multiplyOperatorScenarios = []expressionScenario{
 		document:    mergeDocSample,
 		expression:  `.foobar * .foobarList`,
 		expected: []string{
-			"D0, P[foobar], (!!map)::c: foobarList_c\n!!merge <<: [*foo, *bar]\nthing: foobar_thing\nb: foobarList_b\n",
+			"D0, P[foobar], (!!map)::c: foobarList_c\n<<: [*foo, *bar]\nthing: foobar_thing\nb: foobarList_b\n",
 		},
 	},
 	{
@@ -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",
 		},
 	},
 	{
@@ -581,7 +581,7 @@ var multiplyOperatorScenarios = []expressionScenario{
 		document:    "a: 2\nb: !goat 3.5",
 		expression:  ".a = .a * .b",
 		expected: []string{
-			"D0, P[], (!!map)::a: !!float 7\nb: !goat 3.5\n",
+			"D0, P[], (!!map)::a: 7\nb: !goat 3.5\n",
 		},
 	},
 	{

pkg/yqlib/operator_recursive_descent_test.go

@@ -187,7 +187,7 @@ var recursiveDescentOperatorScenarios = []expressionScenario{
 		document:    mergeDocSample,
 		expression:  `.foobar | [..]`,
 		expected: []string{
-			"D0, P[foobar], (!!seq)::- c: foobar_c\n  !!merge <<: *foo\n  thing: foobar_thing\n- foobar_c\n- *foo\n- foobar_thing\n",
+			"D0, P[foobar], (!!seq)::- c: foobar_c\n  <<: *foo\n  thing: foobar_thing\n- foobar_c\n- *foo\n- foobar_thing\n",
 		},
 	},
 	{
@@ -195,7 +195,7 @@ var recursiveDescentOperatorScenarios = []expressionScenario{
 		document:   mergeDocSample,
 		expression: `.foobar | [...]`,
 		expected: []string{
-			"D0, P[foobar], (!!seq)::- c: foobar_c\n  !!merge <<: *foo\n  thing: foobar_thing\n- c\n- foobar_c\n- !!merge <<\n- *foo\n- thing\n- foobar_thing\n",
+			"D0, P[foobar], (!!seq)::- c: foobar_c\n  <<: *foo\n  thing: foobar_thing\n- c\n- foobar_c\n- <<\n- *foo\n- thing\n- foobar_thing\n",
 		},
 	},
 	{
@@ -203,7 +203,7 @@ var recursiveDescentOperatorScenarios = []expressionScenario{
 		document:   mergeDocSample,
 		expression: `.foobarList | ..`,
 		expected: []string{
-			"D0, P[foobarList], (!!map)::b: foobarList_b\n!!merge <<: [*foo, *bar]\nc: foobarList_c\n",
+			"D0, P[foobarList], (!!map)::b: foobarList_b\n<<: [*foo, *bar]\nc: foobarList_c\n",
 			"D0, P[foobarList b], (!!str)::foobarList_b\n",
 			"D0, P[foobarList <<], (!!seq)::[*foo, *bar]\n",
 			"D0, P[foobarList << 0], (alias)::*foo\n",
@@ -216,7 +216,7 @@ var recursiveDescentOperatorScenarios = []expressionScenario{
 		document:   mergeDocSample,
 		expression: `.foobarList | ...`,
 		expected: []string{
-			"D0, P[foobarList], (!!map)::b: foobarList_b\n!!merge <<: [*foo, *bar]\nc: foobarList_c\n",
+			"D0, P[foobarList], (!!map)::b: foobarList_b\n<<: [*foo, *bar]\nc: foobarList_c\n",
 			"D0, P[foobarList b], (!!str)::b\n",
 			"D0, P[foobarList b], (!!str)::foobarList_b\n",
 			"D0, P[foobarList <<], (!!merge)::<<\n",

pkg/yqlib/operator_select_test.go

@@ -98,7 +98,7 @@ var selectOperatorScenarios = []expressionScenario{
 		document:    `[{animal: cat, legs: {cool: true}}, {animal: fish}]`,
 		expression:  `(.[] | select(.legs.cool == true).canWalk) = true | (.[] | .alive.things) = "yes"`,
 		expected: []string{
-			"D0, P[], (!!seq)::[{animal: cat, legs: {cool: true}, canWalk: true, alive: {things: yes}}, {animal: fish, alive: {things: yes}}]\n",
+			"D0, P[], (!!seq)::[{animal: cat, legs: {cool: true}, canWalk: true, alive: {things: yes}}, {animal: fish,\n        alive: {things: yes}}]\n",
 		},
 	},
 	{

pkg/yqlib/operator_sort_keys_test.go

@@ -37,7 +37,7 @@ var sortKeysOperatorScenarios = []expressionScenario{
 		document:       `{bParent: {c: dog, array: [3,1,2]}, aParent: {z: donkey, x: [{c: yum, b: delish}, {b: ew, a: apple}]}}`,
 		expression:     `sort_keys(..)`,
 		expected: []string{
-			"D0, P[], (!!map)::{aParent: {x: [{b: delish, c: yum}, {a: apple, b: ew}], z: donkey}, bParent: {array: [3, 1, 2], c: dog}}\n",
+			"D0, P[], (!!map)::{aParent: {x: [{b: delish, c: yum}, {a: apple, b: ew}], z: donkey}, bParent: {array: [\n            3, 1, 2], c: dog}}\n",
 		},
 	},
 }

pkg/yqlib/operator_style_test.go

@@ -50,7 +50,7 @@ var styleOperatorScenarios = []expressionScenario{
 		document:   "bing: &foo {x: z}\na:\n  c: cat\n  <<: [*foo]",
 		expression: `(... | select(tag=="!!str")) style="single"`,
 		expected: []string{
-			"D0, P[], (!!map)::'bing': &foo {'x': 'z'}\n'a':\n    'c': 'cat'\n    !!merge <<: [*foo]\n",
+			"D0, P[], (!!map)::'bing': &foo {'x': 'z'}\n'a':\n    'c': 'cat'\n    <<: [*foo]\n",
 		},
 	},
 	{

pkg/yqlib/operator_traverse_path_test.go

@@ -494,7 +494,7 @@ var traversePathOperatorScenarios = []expressionScenario{
 		document:   mergeDocSample,
 		expression: `.foobar`,
 		expected: []string{
-			"D0, P[foobar], (!!map)::c: foobar_c\n!!merge <<: *foo\nthing: foobar_thing\n",
+			"D0, P[foobar], (!!map)::c: foobar_c\n<<: *foo\nthing: foobar_thing\n",
 		},
 	},
 	{
@@ -518,7 +518,7 @@ var traversePathOperatorScenarios = []expressionScenario{
 		document:   mergeDocSample,
 		expression: `.foobarList`,
 		expected: []string{
-			"D0, P[foobarList], (!!map)::b: foobarList_b\n!!merge <<: [*foo, *bar]\nc: foobarList_c\n",
+			"D0, P[foobarList], (!!map)::b: foobarList_b\n<<: [*foo, *bar]\nc: foobarList_c\n",
 		},
 	},
 	{