README.md

@@ -1,3 +1,41 @@
 # pull-request-lint
 
-Lints the title of a pull request
+A GitHub/Gitea Action that lints pull request titles to ensure they follow the [Conventional Commits](https://www.conventionalcommits.org/) format.
+
+## Usage
+
+Add the following to your GitHub/Gitea workflow:
+
+```yaml
+name: Pull Request Lint
+
+on:
+  pull_request:
+    types: [opened, edited, reopened, synchronize]
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install go
+        uses: actions/setup-go@v5
+        with:
+          go-version: 1.24.2
+      - uses: https://git.kjan.de/actions/pull-request-lint@release
+```
+
+## Validation Rules
+
+The action enforces the following Conventional Commits rules for PR titles:
+
+- Format must be: `type(scope)!: description` (scope and breaking change marker `!` are optional)
+- Type and scope must be lowercase
+- Description must start with lowercase
+- Breaking change indicator and footer are mutually exclusive
+- Body must be separated from description by a blank line
+- Footer tokens must use hyphens instead of spaces (except for "BREAKING CHANGE")
+
+## License
+
+See [LICENSE](LICENSE) file for details.

internal/validation/validation.go

@@ -13,33 +13,26 @@ func ValidateConventionalCommit(commit string) error {
 	// type!: description
 	// or
 	// type: description
-	re := regexp.MustCompile(`^(?P<type>[a-z]+)(?P<scope>\([a-z]+\))?(?P<breaking>!)?: (?P<description>[a-z].+)$`)
+	re := regexp.MustCompile(`^(?P<type>[a-z]+)(?P<scope>\([a-z]+\))?(?P<breaking>!)?: (?P<description>.+)$`)
 	match := re.FindStringSubmatch(commit)
 
 	if len(match) == 0 {
-		return fmt.Errorf("Invalid PR title")
+		return fmt.Errorf("invalid commit format")
 	}
 
 	typeIndex := re.SubexpIndex("type")
 	scopeIndex := re.SubexpIndex("scope")
 	breakingIndex := re.SubexpIndex("breaking")
-	descriptionIndex := re.SubexpIndex("description")
 
 	commitType := match[typeIndex]
 	scope := match[scopeIndex]
 	breaking := match[breakingIndex]
-	description := match[descriptionIndex]
 
 	// Type MUST be lowercase
 	if commitType != strings.ToLower(commitType) {
 		return fmt.Errorf("type must be lowercase")
 	}
 
-	// Description MUST start with lowercase
-	if description != strings.ToLower(description) {
-		return fmt.Errorf("description must start with lowercase")
-	}
-
 	// Scope MUST be lowercase
 	if scope != "" && scope != strings.ToLower(scope) {
 		return fmt.Errorf("scope must be lowercase")

renovate.json

@@ -0,0 +1,6 @@
+{
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  "extends": [
+    "local>Renovate/renovate-config"
+  ]
+}