mikefarah · mikefarah · Sep 9, 2025 · Sep 9, 2025
diff --git a/go.mod b/go.mod
@@ -17,7 +17,7 @@ require (
 	github.com/spf13/cobra v1.10.1
 	github.com/spf13/pflag v1.0.10
 	github.com/yuin/gopher-lua v1.1.1
-	go.yaml.in/yaml/v3 v3.0.4
+	go.yaml.in/yaml/v4 v4.0.0-rc.2
 	golang.org/x/net v0.43.0
 	golang.org/x/text v0.28.0
 	gopkg.in/op/go-logging.v1 v1.0.0-20160211212156-b2cb9fa56473

diff --git a/go.sum b/go.sum
@@ -50,16 +50,15 @@ github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5Cc
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/yuin/gopher-lua v1.1.1 h1:kYKnWBjvbNP4XLT3+bPEwAXJx262OhaHDWDVOPjL46M=
 github.com/yuin/gopher-lua v1.1.1/go.mod h1:GBR0iDaNXjAgGg9zfCvksxSRnQx76gclCIb7kdAd1Pw=
-go.yaml.in/yaml/v3 v3.0.4 h1:tfq32ie2Jv2UxXFdLJdh3jXuOzWiL1fo0bu/FbuKpbc=
-go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
+go.yaml.in/yaml/v4 v4.0.0-rc.2 h1:/FrI8D64VSr4HtGIlUtlFMGsm7H7pWTbj6vOLVZcA6s=
+go.yaml.in/yaml/v4 v4.0.0-rc.2/go.mod h1:aZqd9kCMsGL7AuUv/m/PvWLdg5sjJsZ4oHDEnfPPfY0=
 golang.org/x/net v0.43.0 h1:lat02VYK2j4aLzMzecihNvTlJNQUq316m2Mr9rnM6YE=
 golang.org/x/net v0.43.0/go.mod h1:vhO1fvI4dGsIjh73sWfUVjj3N7CA9WkKJNQm2svM6Jg=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.35.0 h1:vz1N37gP5bs89s7He8XuIYXpyY0+QlsKmzipCbUtyxI=
 golang.org/x/sys v0.35.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
 golang.org/x/text v0.28.0 h1:rhazDwis8INMIwQ4tpjLDzUhx6RlXqZNPEM0huQojng=
 golang.org/x/text v0.28.0/go.mod h1:U8nCwOR8jO/marOQ0QbDiOngZVEBB7MAiitBuMjXiNU=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/op/go-logging.v1 v1.0.0-20160211212156-b2cb9fa56473 h1:6D+BvnJ/j6e222UW8s2qTSe3wGBtvo0MbVQG/c5k8RE=
 gopkg.in/op/go-logging.v1 v1.0.0-20160211212156-b2cb9fa56473/go.mod h1:N1eN2tsCx0Ydtgjl4cqmbRCsY4/+z4cYDeqwZTk6zog=

diff --git a/pkg/yqlib/candidate_node_yaml.go b/pkg/yqlib/candidate_node_yaml.go
@@ -3,7 +3,7 @@ package yqlib
 import (
 	"fmt"
 
-	yaml "go.yaml.in/yaml/v3"
+	yaml "go.yaml.in/yaml/v4"
 )
 
 func MapYamlStyle(original yaml.Style) Style {

diff --git a/pkg/yqlib/decoder_yaml.go b/pkg/yqlib/decoder_yaml.go
@@ -8,7 +8,7 @@ import (
 	"regexp"
 	"strings"
 
-	yaml "go.yaml.in/yaml/v3"
+	yaml "go.yaml.in/yaml/v4"
 )
 
 type yamlDecoder struct {

diff --git a/pkg/yqlib/doc/operators/anchor-and-alias-operators.md b/pkg/yqlib/doc/operators/anchor-and-alias-operators.md
@@ -198,12 +198,6 @@ then
 yq 'explode(.f)' sample.yml
 ```
 will output
-```yaml
-f:
-  a: cat
-  cat: b
-```
-
 ## Dereference and update a field
 Use explode with multiply to dereference an object
 
@@ -345,139 +339,3 @@ x: 1
 y: 2
 ```
 
-## FIXED: Explode with merge anchors
-Set `--yaml-fix-merge-anchor-to-spec=true` to get this correct merge behaviour (flag will default to true in late 2025).
-Observe that foobarList.b property is still foobarList_b.
-
-Given a sample.yml file of:
-```yaml
-foo: &foo
-  a: foo_a
-  thing: foo_thing
-  c: foo_c
-bar: &bar
-  b: bar_b
-  thing: bar_thing
-  c: bar_c
-foobarList:
-  b: foobarList_b
-  !!merge <<:
-    - *foo
-    - *bar
-  c: foobarList_c
-foobar:
-  c: foobar_c
-  !!merge <<: *foo
-  thing: foobar_thing
-```
-then
-```bash
-yq 'explode(.)' sample.yml
-```
-will output
-```yaml
-foo:
-  a: foo_a
-  thing: foo_thing
-  c: foo_c
-bar:
-  b: bar_b
-  thing: bar_thing
-  c: bar_c
-foobarList:
-  b: foobarList_b
-  a: foo_a
-  thing: foo_thing
-  c: foobarList_c
-foobar:
-  c: foobar_c
-  a: foo_a
-  thing: foobar_thing
-```
-
-## FIXED: Merge multiple maps
-Set `--yaml-fix-merge-anchor-to-spec=true` to get this correct merge behaviour (flag will default to true in late 2025).
-Taken from https://yaml.org/type/merge.html. Same values as legacy, but with the correct key order.
-
-Given a sample.yml file of:
-```yaml
-- &CENTER
-  x: 1
-  y: 2
-- &LEFT
-  x: 0
-  y: 2
-- &BIG
-  r: 10
-- &SMALL
-  r: 1
-- !!merge <<:
-    - *CENTER
-    - *BIG
-```
-then
-```bash
-yq '.[4] | explode(.)' sample.yml
-```
-will output
-```yaml
-x: 1
-y: 2
-r: 10
-```
-
-## FIXED: Override
-Set `--yaml-fix-merge-anchor-to-spec=true` to get this correct merge behaviour (flag will default to true in late 2025).
-Taken from https://yaml.org/type/merge.html. Same values as legacy, but with the correct key order.
-
-Given a sample.yml file of:
-```yaml
-- &CENTER
-  x: 1
-  y: 2
-- &LEFT
-  x: 0
-  y: 2
-- &BIG
-  r: 10
-- &SMALL
-  r: 1
-- !!merge <<:
-    - *BIG
-    - *LEFT
-    - *SMALL
-  x: 1
-```
-then
-```bash
-yq '.[4] | explode(.)' sample.yml
-```
-will output
-```yaml
-r: 10
-y: 2
-x: 1
-```
-
-## Exploding inline merge anchor
-Set `--yaml-fix-merge-anchor-to-spec=true` to get this correct merge behaviour (flag will default to true in late 2025).
-
-
-Given a sample.yml file of:
-```yaml
-a:
-  b: &b 42
-!!merge <<:
-  c: *b
-```
-then
-```bash
-yq 'explode(.) | sort_keys(.)' sample.yml
-```
-will output
-```yaml
-a:
-  b: 42
-c: 42
-```
-
diff --git a/pkg/yqlib/encoder_yaml.go b/pkg/yqlib/encoder_yaml.go
@@ -9,7 +9,7 @@ import (
 	"strings"
 
 	"github.com/fatih/color"
-	"go.yaml.in/yaml/v3"
+	"go.yaml.in/yaml/v4"
 )
 
 type yamlEncoder struct {

diff --git a/pkg/yqlib/operator_anchors_aliases_test.go b/pkg/yqlib/operator_anchors_aliases_test.go
@@ -464,7 +464,7 @@ var anchorOperatorScenarios = []expressionScenario{
 	},
 	{
 		skipDoc:    true,
-		document:   `{f : {a: &a cat, b: &b {foo: *a}, *a: *b}}`,
+		document:   `{f : {a: &a cat, b: &b {foo: *a}, *a : *b}}`,
 		expression: `explode(.f)`,
 		expected: []string{
 			"D0, P[], (!!map)::{f: {a: cat, b: {foo: cat}, cat: {foo: cat}}}\n",

diff --git a/pkg/yqlib/operators_test.go b/pkg/yqlib/operators_test.go
@@ -385,13 +385,13 @@ func documentOutput(t *testing.T, w *bufio.Writer, s expressionScenario, formatt
 
 		inputs, err = readDocument(formattedDoc, "sample.yml", 0)
 		if err != nil {
-			t.Error(err, s.document, s.expression)
+			t.Error(err, formattedDoc, "exp: "+s.expression)
 			return
 		}
 		if s.document2 != "" {
 			moreInputs, err := readDocument(formattedDoc2, "another.yml", 1)
 			if err != nil {
-				t.Error(err, s.document, s.expression)
+				t.Error(err, formattedDoc2, "exp: "+s.expression)
 				return
 			}
 			inputs.PushBackList(moreInputs)

diff --git a/pkg/yqlib/printer_node_info.go b/pkg/yqlib/printer_node_info.go
@@ -5,7 +5,7 @@ import (
 	"container/list"
 	"io"
 
-	"go.yaml.in/yaml/v3"
+	"go.yaml.in/yaml/v4"
 )
 
 type nodeInfoPrinter struct {