[actions-gh-release] Add labels option in commitCategories

tool/actions-gh-release/release.go

@@ -67,6 +67,7 @@ type ReleaseCommitMatcherConfig struct {
 	ParentOfMergeCommit bool     `json:"parentOfMergeCommit,omitempty"`
 	Prefixes            []string `json:"prefixes,omitempty"`
 	Contains            []string `json:"contains,omitempty"`
+	Labels              []string `json:"labels,omitempty"`
 }
 
 func (c ReleaseCommitMatcherConfig) Empty() bool {
@@ -92,6 +93,17 @@ func (c ReleaseCommitMatcherConfig) Match(commit Commit, mergeCommit *Commit) bo
 	return false
 }
 
+func (c ReleaseCommitMatcherConfig) MatchLabels(labels []*github.Label) bool {
+	for _, cl := range c.Labels {
+		for _, l := range labels {
+			if l.GetName() == cl {
+				return true
+			}
+		}
+	}
+	return false
+}
+
 func (c *ReleaseConfig) Validate() error {
 	if c.Tag == "" {
 		return fmt.Errorf("tag must be specified")
@@ -279,6 +291,14 @@ func buildReleaseCommits(ctx context.Context, ghClient *githubClient, commits []
 		return pr, nil
 	}
 
+	// Whether commitCategory is decided by PR's labels or not.
+	useLabels := false
+	for _, ctg := range cfg.CommitCategories {
+		if len(ctg.Labels) > 0 {
+			useLabels = true
+			break
+		}
+	}
 	out := make([]ReleaseCommit, 0, len(commits))
 	for _, commit := range commits {
 
@@ -298,17 +318,22 @@ func buildReleaseCommits(ctx context.Context, ghClient *githubClient, commits []
 			CategoryName: determineCommitCategory(commit, mergeCommits[commit.Hash], cfg.CommitCategories),
 		}
 
-		if gen.UsePullRequestMetadata {
+		if gen.UsePullRequestMetadata || useLabels {
 			pr, err := getPullRequest(commit)
 			if err != nil {
 				// only error logging, ignore error
 				log.Printf("Failed to get pull request: %v\n", err)
 			}
-			if pr != nil {
+
+			if pr != nil && gen.UsePullRequestMetadata {
 				c.PullRequestNumber = pr.GetNumber()
 				c.PullRequestOwner = pr.GetUser().GetLogin()
 				c.ReleaseNote = extractReleaseNote(pr.GetTitle(), pr.GetBody(), gen.UseReleaseNoteBlock)
 			}
+
+			if pr != nil && useLabels {
+				c.CategoryName = determineCommitCategoryOfPR(pr, cfg.CommitCategories)
+			}
 		}
 
 		out = append(out, c)
@@ -343,6 +368,15 @@ func determineCommitCategory(commit Commit, mergeCommit *Commit, categories []Re
 	return ""
 }
 
+func determineCommitCategoryOfPR(pr *github.PullRequest, categories []ReleaseCommitCategoryConfig) string {
+	for _, c := range categories {
+		if c.ReleaseCommitMatcherConfig.MatchLabels(pr.Labels) {
+			return c.ID
+		}
+	}
+	return ""
+}
+
 func renderReleaseNote(p ReleaseProposal, cfg ReleaseConfig) []byte {
 	var b strings.Builder
 	b.WriteString(fmt.Sprintf("## Release %s with changes since %s\n\n", p.Tag, p.PreTag))

tool/actions-gh-release/release_test.go

@@ -19,6 +19,7 @@ import (
 	"fmt"
 	"testing"
 
+	"github.com/google/go-github/v39/github"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -306,6 +307,79 @@ func TestBuildReleaseCommits(t *testing.T) {
 	}
 }
 
+func TestBuildReleaseCommitsForCategoryLabel(t *testing.T) {
+	t.Parallel()
+
+	cfgs := []ReleaseCommitCategoryConfig{
+		{
+			ID:    "breaking-change",
+			Title: "Breaking Changes",
+			ReleaseCommitMatcherConfig: ReleaseCommitMatcherConfig{
+				Labels: []string{"change-category/breaking-change"},
+			},
+		},
+		{
+			ID:    "notable-change",
+			Title: "Notable Changes",
+			ReleaseCommitMatcherConfig: ReleaseCommitMatcherConfig{
+				Labels: []string{"change-category/notable-change"},
+			},
+		},
+		{
+			ID:                         "internal-change",
+			Title:                      "Internal Changes",
+			ReleaseCommitMatcherConfig: ReleaseCommitMatcherConfig{},
+		},
+	}
+
+	testcases := []struct {
+		title            string
+		labels           []*github.Label
+		categories       []ReleaseCommitCategoryConfig
+		expectedCategory string
+	}{
+		{
+			title:            "no categories config provided",
+			labels:           []*github.Label{},
+			categories:       []ReleaseCommitCategoryConfig{},
+			expectedCategory: "",
+		},
+		{
+			title:            "breaking-change",
+			labels:           []*github.Label{{Name: github.String("change-category/breaking-change")}},
+			categories:       cfgs,
+			expectedCategory: "breaking-change",
+		},
+		{
+			title:            "not match any category",
+			labels:           []*github.Label{{Name: github.String("foo")}},
+			categories:       cfgs,
+			expectedCategory: "",
+		},
+		{
+			title: "matching multiple labels results in the first one defined in config",
+			labels: []*github.Label{
+				{Name: github.String("change-category/notable-change")},
+				{Name: github.String("change-category/breaking-change")},
+			},
+			categories:       cfgs,
+			expectedCategory: "breaking-change",
+		},
+	}
+
+	for _, tc := range testcases {
+		t.Run(tc.title, func(t *testing.T) {
+			t.Parallel()
+
+			pr := &github.PullRequest{
+				Labels: tc.labels,
+			}
+			got := determineCommitCategoryOfPR(pr, tc.categories)
+			assert.Equal(t, tc.expectedCategory, got)
+		})
+	}
+}
+
 func TestRenderReleaseNote(t *testing.T) {
 	testcases := []struct {
 		name     string