Only add commit prefix if branch name matches regex pattern (#3703)

- **PR Description**
Currently if a branch name does not match a regex pattern defined in the
config.yaml (commitPrefix/es) the commit message box is populated with
the branch name as is - this does not match expectations. A prefix
should only be added if there is a match on the regex pattern.

This PR seeks to change that by checking for a match before calling
ReplaceAllString - see Issue #3695

- **Please check if the PR fulfills these requirements**

* [x] Cheatsheets are up-to-date (run `go generate ./...`)
* [x] Code has been formatted (see
[here](https://github.com/jesseduffield/lazygit/blob/master/CONTRIBUTING.md#code-formatting))
* [x] Tests have been added/updated (see
[here](https://github.com/jesseduffield/lazygit/blob/master/pkg/integration/README.md)
for the integration test guide)
* [-] Text is internationalised (see
[here](https://github.com/jesseduffield/lazygit/blob/master/CONTRIBUTING.md#internationalisation))
* [-] Docs have been updated if necessary
* [x] You've read through your own file changes for silly mistakes etc

pkg/gui/controllers/helpers/working_tree_helper.go

@@ -152,12 +152,16 @@ func (self *WorkingTreeHelper) HandleCommitPress() error {
 		if commitPrefixConfig != nil {
 			prefixPattern := commitPrefixConfig.Pattern
 			prefixReplace := commitPrefixConfig.Replace
+			branchName := self.refHelper.GetCheckedOutRef().Name
 			rgx, err := regexp.Compile(prefixPattern)
 			if err != nil {
 				return fmt.Errorf("%s: %s", self.c.Tr.CommitPrefixPatternError, err.Error())
 			}
-			prefix := rgx.ReplaceAllString(self.refHelper.GetCheckedOutRef().Name, prefixReplace)
-			message = prefix
+
+			if rgx.MatchString(branchName) {
+				prefix := rgx.ReplaceAllString(branchName, prefixReplace)
+				message = prefix
+			}
 		}
 	}
 

pkg/integration/tests/commit/commit_with_non_matching_branch_name.go

@@ -0,0 +1,35 @@
+package commit
+
+import (
+	"github.com/jesseduffield/lazygit/pkg/config"
+	. "github.com/jesseduffield/lazygit/pkg/integration/components"
+)
+
+var CommitWithNonMatchingBranchName = NewIntegrationTest(NewIntegrationTestArgs{
+	Description:  "Commit with defined config commitPrefixes",
+	ExtraCmdArgs: []string{},
+	Skip:         false,
+	SetupConfig: func(testConfig *config.AppConfig) {
+		testConfig.UserConfig.Git.CommitPrefix = &config.CommitPrefixConfig{
+			Pattern: "^\\w+\\/(\\w+-\\w+).*",
+			Replace: "[$1]: ",
+		}
+	},
+	SetupRepo: func(shell *Shell) {
+		shell.NewBranch("branchnomatch")
+		shell.CreateFile("test-commit-prefix", "This is foo bar")
+	},
+	Run: func(t *TestDriver, keys config.KeybindingConfig) {
+		t.Views().Commits().
+			IsEmpty()
+
+		t.Views().Files().
+			IsFocused().
+			PressPrimaryAction().
+			Press(keys.Files.CommitChanges)
+
+		t.ExpectPopup().CommitMessagePanel().
+			Title(Equals("Commit summary")).
+			InitialText(Equals(""))
+	},
+})

pkg/integration/tests/test_list.go

@@ -80,6 +80,7 @@ var tests = []*components.IntegrationTest{
 	commit.CommitSwitchToEditor,
 	commit.CommitWipWithPrefix,
 	commit.CommitWithGlobalPrefix,
+	commit.CommitWithNonMatchingBranchName,
 	commit.CommitWithPrefix,
 	commit.CreateAmendCommit,
 	commit.CreateTag,