Try branch color patterns in the order they are written

If several patterns in gui.branchColorPatterns match a branch, the color
it gets is picked at random, and it can change from one render to the
next. The patterns are kept in a Go map, and Go randomizes the order in
which a map is iterated.

Keep the patterns in a list instead, in the order in which they are
written, and let the first match win. If a repo's config file has
patterns too, put them in front of those of the global config file,
because they are more specific.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

docs-master/Config.md

@@ -1069,6 +1069,8 @@ gui:
 
 Note that the regular expressions are not implicitly anchored to the beginning/end of the branch name. If you want to do that, add leading `^` and/or trailing `$` as needed.
 
+If several patterns match a branch, the first one wins.
+
 ## Custom Files Icon & Color
 
 You can customize the icon and color of files based on filenames or extensions:

pkg/config/color_patterns.go

@@ -0,0 +1,69 @@
+package config
+
+import (
+	"slices"
+
+	"github.com/karimkhaleel/jsonschema"
+	"github.com/samber/lo"
+	"gopkg.in/yaml.v3"
+)
+
+// ColorPatterns assigns colors to the names that match regular expressions.
+// It's written in YAML as a mapping from pattern to color, and keeps the
+// patterns in the order in which they are written, so that the first pattern
+// that matches a name can decide its color.
+type ColorPatterns []ColorPattern
+
+type ColorPattern struct {
+	Pattern string
+	Color   string
+}
+
+// UnmarshalYAML puts the patterns it reads in front of the ones that are there
+// already, which come from config files that were loaded earlier.
+func (p *ColorPatterns) UnmarshalYAML(node *yaml.Node) error {
+	// Decoding into a map reports malformed input the same way as for the
+	// other maps in the config.
+	var colors map[string]string
+	if err := node.Decode(&colors); err != nil {
+		return err
+	}
+
+	patterns := make(ColorPatterns, 0, len(colors))
+	for i := 0; i < len(node.Content)-1; i += 2 {
+		var pattern string
+		if err := node.Content[i].Decode(&pattern); err != nil {
+			return err
+		}
+		patterns = append(patterns, ColorPattern{Pattern: pattern, Color: colors[pattern]})
+	}
+
+	*p = patterns.over(*p)
+	return nil
+}
+
+func (p ColorPatterns) MarshalYAML() (any, error) {
+	node := &yaml.Node{Kind: yaml.MappingNode}
+	for _, pattern := range p {
+		node.Content = append(node.Content,
+			&yaml.Node{Kind: yaml.ScalarNode, Tag: "!!str", Value: pattern.Pattern},
+			&yaml.Node{Kind: yaml.ScalarNode, Tag: "!!str", Value: pattern.Color},
+		)
+	}
+	return node, nil
+}
+
+// JSONSchema describes the patterns as the mapping they are written as.
+func (ColorPatterns) JSONSchema() *jsonschema.Schema {
+	return &jsonschema.Schema{
+		Type:                 "object",
+		AdditionalProperties: &jsonschema.Schema{Type: "string"},
+	}
+}
+
+// over returns p followed by the patterns of lower that p doesn't have.
+func (p ColorPatterns) over(lower ColorPatterns) ColorPatterns {
+	return slices.Concat(p, lo.Reject(lower, func(l ColorPattern, _ int) bool {
+		return slices.ContainsFunc(p, func(c ColorPattern) bool { return c.Pattern == l.Pattern })
+	}))
+}

pkg/config/color_patterns_test.go

@@ -0,0 +1,64 @@
+package config
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"gopkg.in/yaml.v3"
+)
+
+type colorPatternsConfig struct {
+	Patterns ColorPatterns `yaml:"patterns"`
+}
+
+func TestColorPatternsKeepTheirOrder(t *testing.T) {
+	var config colorPatternsConfig
+	err := yaml.Unmarshal([]byte("patterns:\n"+
+		"  '^b': red\n"+
+		"  '^a': '#00ff00'\n"+
+		"  '^c': blue\n"), &config)
+	assert.NoError(t, err)
+	assert.Equal(t, ColorPatterns{
+		{Pattern: "^b", Color: "red"},
+		{Pattern: "^a", Color: "#00ff00"},
+		{Pattern: "^c", Color: "blue"},
+	}, config.Patterns)
+}
+
+func TestColorPatternsOfALaterFileComeFirst(t *testing.T) {
+	var config colorPatternsConfig
+	err := yaml.Unmarshal([]byte("patterns:\n"+
+		"  '^a': red\n"+
+		"  '^b': green\n"), &config)
+	assert.NoError(t, err)
+	err = yaml.Unmarshal([]byte("patterns:\n"+
+		"  '^c': blue\n"+
+		"  '^b': yellow\n"), &config)
+	assert.NoError(t, err)
+	assert.Equal(t, ColorPatterns{
+		{Pattern: "^c", Color: "blue"},
+		{Pattern: "^b", Color: "yellow"},
+		{Pattern: "^a", Color: "red"},
+	}, config.Patterns)
+}
+
+func TestColorPatternsMustBeAMapping(t *testing.T) {
+	var config colorPatternsConfig
+	err := yaml.Unmarshal([]byte("patterns: 5\n"), &config)
+	assert.ErrorContains(t, err, "cannot unmarshal !!int `5` into map[string]string")
+}
+
+func TestColorPatternsSurviveMarshalling(t *testing.T) {
+	config := colorPatternsConfig{Patterns: ColorPatterns{
+		{Pattern: "^b", Color: "red"},
+		{Pattern: "^a", Color: "#00ff00"},
+		{Pattern: "true", Color: "blue"},
+	}}
+	content, err := yaml.Marshal(config)
+	assert.NoError(t, err)
+
+	var roundTripped colorPatternsConfig
+	err = yaml.Unmarshal(content, &roundTripped)
+	assert.NoError(t, err)
+	assert.Equal(t, config, roundTripped)
+}

pkg/config/user_config.go

@@ -71,7 +71,7 @@ type GuiConfig struct {
 	// See https://github.com/jesseduffield/lazygit/blob/master/docs/Config.md#custom-author-color
 	AuthorColors map[string]string `yaml:"authorColors"`
 	// See https://github.com/jesseduffield/lazygit/blob/master/docs/Config.md#custom-branch-color
-	BranchColorPatterns map[string]string `yaml:"branchColorPatterns"`
+	BranchColorPatterns ColorPatterns `yaml:"branchColorPatterns"`
 	// Custom icons for filenames and file extensions
 	// See https://github.com/jesseduffield/lazygit/blob/master/docs/Config.md#custom-files-icon--color
 	CustomIcons CustomIconsConfig `yaml:"customIcons"`

pkg/gui/presentation/branches.go

@@ -19,11 +19,12 @@ import (
 	"github.com/samber/lo"
 )
 
-type colorMatcher struct {
-	patterns map[string]*style.TextStyle
+type branchColorPattern struct {
+	pattern string
+	style   style.TextStyle
 }
 
-var colorPatterns *colorMatcher
+var branchColorPatterns []branchColorPattern
 
 func GetBranchListDisplayStrings(
 	branches []*models.Branch,
@@ -192,21 +193,13 @@ func getBranchDisplayStrings(
 
 // GetBranchTextStyle branch color
 func GetBranchTextStyle(name string) style.TextStyle {
-	if style, ok := colorPatterns.match(name); ok {
-		return *style
-	}
-
-	return theme.DefaultTextColor
-}
-
-func (m *colorMatcher) match(name string) (*style.TextStyle, bool) {
-	for pattern, style := range m.patterns {
-		if matched, _ := regexp.MatchString(pattern, name); matched {
-			return style, true
+	for _, p := range branchColorPatterns {
+		if matched, _ := regexp.MatchString(p.pattern, name); matched {
+			return p.style
 		}
 	}
 
-	return nil, false
+	return theme.DefaultTextColor
 }
 
 func BranchStatus(
@@ -262,10 +255,10 @@ func divergenceStr(
 	return result
 }
 
-func SetCustomBranches(customBranchColors map[string]string) {
-	colorPatterns = &colorMatcher{
-		patterns: utils.SetCustomColors(customBranchColors),
-	}
+func SetCustomBranches(patterns config.ColorPatterns) {
+	branchColorPatterns = lo.Map(patterns, func(p config.ColorPattern, _ int) branchColorPattern {
+		return branchColorPattern{pattern: p.Pattern, style: utils.CustomColorStyle(p.Color)}
+	})
 }
 
 func WithPrColor(state string, text string, isBg bool) string {

pkg/gui/presentation/branches_test.go

@@ -2,6 +2,7 @@ package presentation
 
 import (
 	"fmt"
+	"slices"
 	"sync/atomic"
 	"testing"
 	"time"
@@ -9,10 +10,12 @@ import (
 	"github.com/gookit/color"
 	"github.com/jesseduffield/lazygit/pkg/commands/models"
 	"github.com/jesseduffield/lazygit/pkg/common"
+	"github.com/jesseduffield/lazygit/pkg/config"
 	"github.com/jesseduffield/lazygit/pkg/gui/presentation/icons"
 	"github.com/jesseduffield/lazygit/pkg/gui/style"
 	"github.com/jesseduffield/lazygit/pkg/gui/types"
 	"github.com/jesseduffield/lazygit/pkg/i18n"
+	"github.com/jesseduffield/lazygit/pkg/theme"
 	"github.com/samber/lo"
 	"github.com/stretchr/testify/assert"
 	"github.com/xo/terminfo"
@@ -436,3 +439,21 @@ func Test_getBranchDisplayStrings(t *testing.T) {
 		})
 	}
 }
+
+func TestGetBranchTextStyle(t *testing.T) {
+	defer SetCustomBranches(nil)
+
+	patterns := config.ColorPatterns{
+		{Pattern: "^feature/", Color: "green"},
+		{Pattern: `ISSUE-\d+`, Color: "red"},
+	}
+
+	SetCustomBranches(patterns)
+	assert.Equal(t, style.FgGreen, GetBranchTextStyle("feature/ISSUE-1"))
+	assert.Equal(t, style.FgRed, GetBranchTextStyle("fix/ISSUE-1"))
+	assert.Equal(t, theme.DefaultTextColor, GetBranchTextStyle("main"))
+
+	slices.Reverse(patterns)
+	SetCustomBranches(patterns)
+	assert.Equal(t, style.FgRed, GetBranchTextStyle("feature/ISSUE-1"))
+}

schema-master/config.json

@@ -3,6 +3,13 @@
   "$id": "https://github.com/jesseduffield/lazygit/pkg/config/user-config",
   "$ref": "#/$defs/UserConfig",
   "$defs": {
+    "ColorPatterns": {
+      "additionalProperties": {
+        "type": "string"
+      },
+      "type": "object",
+      "description": "See https://github.com/jesseduffield/lazygit/blob/master/docs/Config.md#custom-branch-color"
+    },
     "CommitConfig": {
       "properties": {
         "signOff": {
@@ -538,10 +545,7 @@
           "description": "See https://github.com/jesseduffield/lazygit/blob/master/docs/Config.md#custom-author-color"
         },
         "branchColorPatterns": {
-          "additionalProperties": {
-            "type": "string"
-          },
-          "type": "object",
+          "$ref": "#/$defs/ColorPatterns",
           "description": "See https://github.com/jesseduffield/lazygit/blob/master/docs/Config.md#custom-branch-color"
         },
         "customIcons": {