Improve output format

go.mod

@@ -8,7 +8,7 @@ require (
 	github.com/stretchr/testify v1.10.0
 )
 
-require golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
+require golang.org/x/xerrors v0.0.0-20240903120638-7835f813f4da // indirect
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect

go.sum

@@ -35,8 +35,8 @@ golang.org/x/crypto v0.7.0/go.mod h1:pYwdfH91IfpZVANVyUOhSIPZaFoJGxTFbZhFTx+dXZU
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.29.0 h1:TPYlXGxvx1MGTn2GiZDhnjPA9wZzZeGKHHmKhHYvgaU=
 golang.org/x/sys v0.29.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20240903120638-7835f813f4da h1:noIWHXmPHxILtqtCOPIhSt0ABwskkZKjD3bXGnZGpNY=
+golang.org/x/xerrors v0.0.0-20240903120638-7835f813f4da/go.mod h1:NDW/Ps6MPRej6fsCIbMTohpP40sJ/P/vI1MoTEGwX90=
 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/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

pkg/diff/ast_compare.go

@@ -1,9 +1,6 @@
 package diff
 
 import (
-	"fmt"
-	"strings"
-
 	"github.com/goccy/go-yaml/ast"
 )
 
@@ -176,32 +173,3 @@ func ignoreIndexes(diffs []*Diff, opts DiffOptions) []*Diff {
 
 	return resultDiffs
 }
-
-func nodePathString(n ast.Node) string {
-	path := n.GetPath()[2:]
-	// Path of the MappingNode points to the first key in the map.
-	if n.Type() == ast.MappingType {
-		path = path[:strings.LastIndex(path, ".")]
-	}
-	return path
-}
-
-func nodeValueString(n ast.Node) string {
-	switch n.Type() {
-	case ast.MappingType, ast.SequenceType:
-		indent := n.GetToken().Position.IndentNum
-		s := n.String()
-		lines := strings.Split(s, "\n")
-		for i, line := range lines {
-			lines[i] = fmt.Sprintf("  %s", line[indent:])
-		}
-		s = strings.Join(lines, "\n")
-		return fmt.Sprintf("\n%s", s)
-	default:
-		return n.String()
-	}
-}
-
-func nodeMetadata(n ast.Node) string {
-	return fmt.Sprintf("[line:%d <%s>]", n.GetToken().Position.Line, n.Type())
-}

pkg/diff/diff.go

@@ -20,13 +20,13 @@ func (d *Diff) Format(opts FormatOptions) string {
 	if d.leftNode == nil { // Added
 		sign := "+"
 		path := nodePathString(d.rightNode)
-		value := nodeValueString(d.rightNode)
+		value, _ := nodeValueString(d.rightNode, 4)
 		metadata := nodeMetadata(d.rightNode)
 
 		if !opts.Plain {
 			sign = color.HiGreenString(sign)
 			path = color.HiGreenString(path)
-			value = color.HiWhiteString(value)
+			value = colorize(value)
 			metadata = color.HiCyanString(metadata)
 		}
 
@@ -43,13 +43,13 @@ func (d *Diff) Format(opts FormatOptions) string {
 	} else if d.rightNode == nil { //Deleted
 		sign := "-"
 		path := nodePathString(d.leftNode)
-		value := nodeValueString(d.leftNode)
+		value, _ := nodeValueString(d.leftNode, 4)
 		metadata := nodeMetadata(d.leftNode)
 
 		if !opts.Plain {
 			sign = color.HiRedString(sign)
 			path = color.HiRedString(path)
-			value = color.HiWhiteString(value)
+			value = colorize(value)
 			metadata = color.HiCyanString(metadata)
 		}
 
@@ -65,16 +65,32 @@ func (d *Diff) Format(opts FormatOptions) string {
 	} else { //Modified
 		sign := "~"
 		path := nodePathString(d.leftNode)
-		leftValue := nodeValueString(d.leftNode)
-		rightValue := nodeValueString(d.rightNode)
+		leftValue, leftMultiLine := nodeValueString(d.leftNode, 4)
+		rightValue, rightMultiLine := nodeValueString(d.rightNode, 4)
 		leftMetadata := nodeMetadata(d.leftNode)
 		rightMetadata := nodeMetadata(d.rightNode)
 
+		symbol := "->"
+
+		multiline := leftMultiLine || rightMultiLine
+
+		if multiline && !leftMultiLine {
+			leftValue = fmt.Sprintf("\n    %s", leftValue)
+		}
+
+		if multiline && !rightMultiLine {
+			rightValue = fmt.Sprintf("\n    %s", rightValue)
+		}
+
+		if multiline {
+			symbol = "\n    ↓"
+		}
+
 		if !opts.Plain {
 			sign = color.HiYellowString(sign)
 			path = color.HiYellowString(path)
-			leftValue = color.HiWhiteString(leftValue)
-			rightValue = color.HiWhiteString(rightValue)
+			leftValue = colorize(leftValue)
+			rightValue = colorize(rightValue)
 			leftMetadata = color.HiCyanString(leftMetadata)
 			rightMetadata = color.HiCyanString(rightMetadata)
 		}
@@ -83,9 +99,9 @@ func (d *Diff) Format(opts FormatOptions) string {
 			b.WriteString(fmt.Sprintf("%s %s", sign, path))
 		} else {
 			if opts.Metadata {
-				b.WriteString(fmt.Sprintf("%s %s: %s %s -> %s %s", sign, path, leftMetadata, leftValue, rightMetadata, rightValue))
+				b.WriteString(fmt.Sprintf("%s %s: %s %s %s %s %s", sign, path, leftMetadata, leftValue, symbol, rightMetadata, rightValue))
 			} else {
-				b.WriteString(fmt.Sprintf("%s %s: %s -> %s", sign, path, leftValue, rightValue))
+				b.WriteString(fmt.Sprintf("%s %s: %s %s %s", sign, path, leftValue, symbol, rightValue))
 			}
 		}
 	}

pkg/diff/format.go

@@ -0,0 +1,111 @@
+package diff
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/fatih/color"
+	"github.com/goccy/go-yaml/ast"
+	"github.com/goccy/go-yaml/lexer"
+	"github.com/goccy/go-yaml/printer"
+)
+
+func nodePathString(n ast.Node) string {
+	path := n.GetPath()[2:]
+	// Path of the MappingNode points to the first key in the map.
+	if n.Type() == ast.MappingType {
+		path = path[:strings.LastIndex(path, ".")]
+	}
+	return path
+}
+
+func nodeValueString(n ast.Node, indent int) (string, bool) {
+	s := n.String()
+	lines := strings.Split(s, "\n")
+	if len(lines) == 1 {
+		return s, false
+	}
+
+	nodeIndentLevel := 0
+	for i, line := range lines {
+		if i == 0 {
+			nodeIndentLevel = findIndentLevel(line)
+			lines[i] = fmt.Sprintf("%s%s%s", "\n", strings.Repeat(" ", indent), line[nodeIndentLevel:])
+		} else {
+			lines[i] = fmt.Sprintf("%s%s", strings.Repeat(" ", indent), line[nodeIndentLevel:])
+		}
+	}
+
+	return strings.Join(lines, "\n"), true
+}
+
+func nodeMetadata(n ast.Node) string {
+	return fmt.Sprintf("[line:%d <%s>]", n.GetToken().Position.Line, n.Type())
+}
+
+func findIndentLevel(s string) int {
+	for i, c := range s {
+		if c != ' ' {
+			return i
+		}
+	}
+	return 0
+}
+
+var p printer.Printer
+
+func init() {
+	p = printer.Printer{}
+	//p.LineNumber = true
+	//p.LineNumberFormat = func(num int) string {
+	//	fn := color.New(color.Bold, color.FgHiWhite).SprintFunc()
+	//	return fn(fmt.Sprintf("%2d | ", num))
+	//}
+	p.Bool = func() *printer.Property {
+		return &printer.Property{
+			Prefix: format(color.FgHiMagenta),
+			Suffix: format(color.Reset),
+		}
+	}
+	p.Number = func() *printer.Property {
+		return &printer.Property{
+			Prefix: format(color.FgHiMagenta),
+			Suffix: format(color.Reset),
+		}
+	}
+	p.MapKey = func() *printer.Property {
+		return &printer.Property{
+			Prefix: format(color.FgHiCyan),
+			Suffix: format(color.Reset),
+		}
+	}
+	p.Anchor = func() *printer.Property {
+		return &printer.Property{
+			Prefix: format(color.FgHiYellow),
+			Suffix: format(color.Reset),
+		}
+	}
+	p.Alias = func() *printer.Property {
+		return &printer.Property{
+			Prefix: format(color.FgHiYellow),
+			Suffix: format(color.Reset),
+		}
+	}
+	p.String = func() *printer.Property {
+		return &printer.Property{
+			Prefix: format(color.FgHiGreen),
+			Suffix: format(color.Reset),
+		}
+	}
+}
+
+const escape = "\x1b"
+
+func format(attr color.Attribute) string {
+	return fmt.Sprintf("%s[%dm", escape, attr)
+}
+
+func colorize(s string) string {
+	tokens := lexer.Tokenize(s)
+	return p.PrintTokens(tokens)
+}