fix: use compact indent for sequences

We had some grumbles from developers after the goyaml.v3 upgrade that
this changed the sequence indent used by kustomize, kubectl etc.

There was a whole thread about this when the goyaml.v3 upgrade happened
in kustomize itself: kubernetes-sigs/kustomize#3946
and the result was that kubesigs forked goyaml.

In order to more closely match what the kubernetes tools do, this commit
switches to the forked version, which has a compact option on the
encoder:
https://github.com/kubernetes-sigs/yaml/blob/56d672052dcff7362af5b66f6424976539cddd78/goyaml.v3/patch.go#L25-L28

When I first tried this I also changed the code to guess if compact
was the preferred style from the yaml. However, it turns out that
the yaml formatter misbehaves when told to use "compact" and an indent
other than 2; if set to 3 and compact it produces code like this:

    mapping:
     - list item

Instead of:

    mapping:
       - list item

This meant I couldn't get the "guess indentation" code to work, so
I've removed that and its test to avoid raising a fault expectation.

Signed-off-by: Brian Ewins <bewins@nerdwallet.com>

Author: bewinsnw

go.mod

@@ -24,12 +24,12 @@ require (
 	golang.org/x/oauth2 v0.27.0
 	golang.org/x/sync v0.11.0
 	google.golang.org/grpc v1.70.0
-	gopkg.in/yaml.v3 v3.0.1
 	k8s.io/api v0.31.0
 	k8s.io/apimachinery v0.31.0
 	k8s.io/client-go v0.31.0
 	sigs.k8s.io/kustomize/api v0.17.2
 	sigs.k8s.io/kustomize/kyaml v0.17.1
+	sigs.k8s.io/yaml v1.4.0
 )
 
 require (
@@ -153,6 +153,7 @@ require (
 	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/warnings.v0 v0.1.2 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 	k8s.io/apiextensions-apiserver v0.31.2 // indirect
 	k8s.io/apiserver v0.31.0 // indirect
 	k8s.io/cli-runtime v0.31.0 // indirect
@@ -167,7 +168,6 @@ require (
 	oras.land/oras-go/v2 v2.5.0 // indirect
 	sigs.k8s.io/json v0.0.0-20221116044647-bc3834ca7abd // indirect
 	sigs.k8s.io/structured-merge-diff/v4 v4.4.1 // indirect
-	sigs.k8s.io/yaml v1.4.0 // indirect
 )
 
 replace (

pkg/argocd/update.go

@@ -22,7 +22,7 @@ import (
 
 	"github.com/argoproj/argo-cd/v2/pkg/apiclient/application"
 	"github.com/argoproj/argo-cd/v2/pkg/apis/application/v1alpha1"
-	"gopkg.in/yaml.v3"
+	yaml "sigs.k8s.io/yaml/goyaml.v3"
 )
 
 // Stores some statistics about the results of a run
@@ -61,6 +61,8 @@ const (
 	WriteBackGit         WriteBackMethod = 1
 )
 
+const defaultIndent = 2
+
 // WriteBackConfig holds information on how to write back the changes to an Application
 type WriteBackConfig struct {
 	Method     WriteBackMethod
@@ -425,6 +427,7 @@ func marshalWithIndent(in interface{}, indent int) (out []byte, err error) {
 	defer encoder.Close()
 	// note: yaml.v3 will only respect indents from 1 to 9 inclusive.
 	encoder.SetIndent(indent)
+	encoder.CompactSeqIndent()
 	if err = encoder.Encode(in); err != nil {
 		return nil, err
 	}
@@ -434,30 +437,6 @@ func marshalWithIndent(in interface{}, indent int) (out []byte, err error) {
 	return b.Bytes(), nil
 }
 
-func guessIndent(root *yaml.Node) int {
-	node := root
-	if root.Kind == yaml.DocumentNode {
-		if len(node.Content) == 0 {
-			return 2
-		}
-		node = root.Content[0]
-	}
-	// anything other than a map at the root makes guessing difficult
-	if node.Kind != yaml.MappingNode || len(node.Content) == 0 {
-		return 2
-	}
-	// first level map entries that are themselves mappings or sequences,
-	// in block style, and are indented, allow guessing the preferred indent.
-	for i, child := range node.Content {
-		if i%2 == 1 && child.Column > 1 && child.Column < 10 && child.Style != yaml.FlowStyle {
-			if child.Kind == yaml.MappingNode || child.Kind == yaml.SequenceNode {
-				return child.Column - 1
-			}
-		}
-	}
-	return 2
-}
-
 // marshalParamsOverride marshals the parameter overrides of a given application
 // into YAML bytes
 func marshalParamsOverride(app *v1alpha1.Application, originalData []byte) ([]byte, error) {
@@ -481,16 +460,16 @@ func marshalParamsOverride(app *v1alpha1.Application, originalData []byte) ([]by
 		}
 
 		if len(originalData) == 0 {
-			override, err = marshalWithIndent(newParams, 2)
+			override, err = marshalWithIndent(newParams, defaultIndent)
 			break
 		}
 		err = yaml.Unmarshal(originalData, &params)
 		if err != nil {
-			override, err = marshalWithIndent(newParams, 2)
+			override, err = marshalWithIndent(newParams, defaultIndent)
 			break
 		}
 		mergeKustomizeOverride(&params, &newParams)
-		override, err = marshalWithIndent(params, 2)
+		override, err = marshalWithIndent(params, defaultIndent)
 	case ApplicationTypeHelm:
 		if appSource.Helm == nil {
 			return []byte{}, nil
@@ -504,7 +483,6 @@ func marshalParamsOverride(app *v1alpha1.Application, originalData []byte) ([]by
 			if err != nil {
 				return nil, err
 			}
-			indent := guessIndent(&helmNewValues)
 
 			for _, c := range images {
 				if c.ImageAlias == "" {
@@ -546,7 +524,7 @@ func marshalParamsOverride(app *v1alpha1.Application, originalData []byte) ([]by
 				}
 			}
 
-			override, err = marshalWithIndent(&helmNewValues, indent)
+			override, err = marshalWithIndent(&helmNewValues, defaultIndent)
 		} else {
 			var params helmOverride
 			newParams := helmOverride{
@@ -559,16 +537,16 @@ func marshalParamsOverride(app *v1alpha1.Application, originalData []byte) ([]by
 			log.WithContext().AddField("application", app).Debugf("values: '%s'", outputParams)
 
 			if len(originalData) == 0 {
-				override, err = marshalWithIndent(newParams, 2)
+				override, err = marshalWithIndent(newParams, defaultIndent)
 				break
 			}
 			err = yaml.Unmarshal(originalData, &params)
 			if err != nil {
-				override, err = marshalWithIndent(newParams, 2)
+				override, err = marshalWithIndent(newParams, defaultIndent)
 				break
 			}
 			mergeHelmOverride(&params, &newParams)
-			override, err = marshalWithIndent(params, 2)
+			override, err = marshalWithIndent(params, defaultIndent)
 		}
 	default:
 		err = fmt.Errorf("unsupported application type")