fix(librarian): filter commits by library id (#2537)

Fixes #2529

Author: parthea

internal/librarian/commit_version_analyzer.go

@@ -96,6 +96,25 @@ func shouldIncludeForGeneration(files, apiPaths []string) bool {
 	return false
 }
 
+// libraryFilter filters a list of conventional commits by library ID.
+func libraryFilter(commits []*conventionalcommits.ConventionalCommit, libraryID string) []*conventionalcommits.ConventionalCommit {
+	var filteredCommits []*conventionalcommits.ConventionalCommit
+	for _, commit := range commits {
+		if libraryIDs, ok := commit.Footers["Library-IDs"]; ok {
+			ids := strings.Split(libraryIDs, ",")
+			for _, id := range ids {
+				if strings.TrimSpace(id) == libraryID {
+					filteredCommits = append(filteredCommits, commit)
+					break
+				}
+			}
+		} else if commit.LibraryID == libraryID {
+			filteredCommits = append(filteredCommits, commit)
+		}
+	}
+	return filteredCommits
+}
+
 // convertToConventionalCommits converts a list of commits in a git repo into a list
 // of conventional commits. The filesFilter parameter is custom filter out non-matching
 // files depending on a generation or a release change.
@@ -116,6 +135,9 @@ func convertToConventionalCommits(repo gitrepo.Repository, library *config.Libra
 		if parsedCommits == nil {
 			continue
 		}
+
+		parsedCommits = libraryFilter(parsedCommits, library.ID)
+
 		for _, pc := range parsedCommits {
 			pc.CommitHash = commit.Hash.String()
 		}

internal/librarian/commit_version_analyzer_test.go

@@ -180,7 +180,9 @@ func TestShouldIncludeForGeneration(t *testing.T) {
 }
 
 func TestGetConventionalCommitsSinceLastRelease(t *testing.T) {
+
 	t.Parallel()
+
 	pathAndMessages := []pathAndMessage{
 		{
 			path:    "foo/a.txt",
@@ -202,8 +204,46 @@ func TestGetConventionalCommitsSinceLastRelease(t *testing.T) {
 			path:    "foo/c.txt",
 			message: "feat(foo): another feature for foo",
 		},
+		{
+			path: "foo/something.txt",
+			message: `BEGIN_COMMIT_OVERRIDE 
+
+BEGIN_NESTED_COMMIT
+fix: a bug1 fix
+
+This is another body.
+
+PiperOrigin-RevId: 573342
+Library-IDs: foo
+Source-link: [googleapis/googleapis@fedcba0](https://github.com/googleapis/googleapis/commit/fedcba0)
+END_NESTED_COMMIT
+
+BEGIN_NESTED_COMMIT
+fix: a bug2 fix
+
+This is another body.
+
+PiperOrigin-RevId: 573342
+Library-IDs: bar
+Source-link: [googleapis/googleapis@fedcba0](https://github.com/googleapis/googleapis/commit/fedcba0)
+END_NESTED_COMMIT
+
+BEGIN_NESTED_COMMIT
+fix: a bug3 fix
+
+This is another body.
+
+PiperOrigin-RevId: 573342
+Library-IDs: foo, bar
+Source-link: [googleapis/googleapis@fedcba0](https://github.com/googleapis/googleapis/commit/fedcba0)
+END_NESTED_COMMIT
+
+END_COMMIT_OVERRIDE`,
+		},
 	}
+
 	repoWithCommits := setupRepoForGetCommits(t, pathAndMessages, []string{"foo-v1.0.0"})
+
 	for _, test := range []struct {
 		name          string
 		repo          gitrepo.Repository
@@ -223,6 +263,28 @@ func TestGetConventionalCommitsSinceLastRelease(t *testing.T) {
 				ReleaseExcludePaths: []string{"foo/README.md"},
 			},
 			want: []*conventionalcommits.ConventionalCommit{
+				{
+					Type:      "fix",
+					Subject:   "a bug1 fix",
+					LibraryID: "foo",
+					Footers: map[string]string{
+						"PiperOrigin-RevId": "573342",
+						"Library-IDs":       "foo",
+						"Source-link":       "[googleapis/googleapis@fedcba0](https://github.com/googleapis/googleapis/commit/fedcba0)",
+					},
+					IsNested: true,
+				},
+				{
+					Type:      "fix",
+					Subject:   "a bug3 fix",
+					LibraryID: "foo",
+					Footers: map[string]string{
+						"PiperOrigin-RevId": "573342",
+						"Library-IDs":       "foo, bar",
+						"Source-link":       "[googleapis/googleapis@fedcba0](https://github.com/googleapis/googleapis/commit/fedcba0)",
+					},
+					IsNested: true,
+				},
 				{
 					Type:      "feat",
 					Scope:     "foo",
@@ -574,3 +636,75 @@ func TestNextVersion(t *testing.T) {
 		})
 	}
 }
+
+func TestLibraryFilter(t *testing.T) {
+	t.Parallel()
+	commits := []*conventionalcommits.ConventionalCommit{
+		{
+			LibraryID: "foo",
+			Footers:   map[string]string{},
+		},
+		{
+			LibraryID: "bar",
+			Footers:   map[string]string{},
+		},
+		{
+			Footers: map[string]string{
+				"Library-IDs": "foo",
+			},
+		},
+		{
+			Footers: map[string]string{
+				"Library-IDs": "bar",
+			},
+		},
+		{
+			Footers: map[string]string{
+				"Library-IDs": "foo, bar",
+			},
+		},
+		{
+			Footers: map[string]string{
+				"Library-IDs": "foo,bar",
+			},
+		},
+	}
+	for _, test := range []struct {
+		name      string
+		libraryID string
+		want      []*conventionalcommits.ConventionalCommit
+	}{
+		{
+			name:      "filter by foo",
+			libraryID: "foo",
+			want: []*conventionalcommits.ConventionalCommit{
+				commits[0],
+				commits[2],
+				commits[4],
+				commits[5],
+			},
+		},
+		{
+			name:      "filter by bar",
+			libraryID: "bar",
+			want: []*conventionalcommits.ConventionalCommit{
+				commits[1],
+				commits[3],
+				commits[4],
+				commits[5],
+			},
+		},
+		{
+			name:      "filter by baz",
+			libraryID: "baz",
+			want:      nil,
+		},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			got := libraryFilter(commits, test.libraryID)
+			if diff := cmp.Diff(test.want, got); diff != "" {
+				t.Errorf("libraryFilter() mismatch (-want +got):\n%s", diff)
+			}
+		})
+	}
+}