refactor: move changelog file to updater interface (#15)

changelog.go

@@ -3,14 +3,8 @@ package rp
 import (
 	"bytes"
 	_ "embed"
-	"fmt"
 	"html/template"
-	"io"
 	"log"
-	"os"
-	"regexp"
-
-	"github.com/go-git/go-git/v5"
 )
 
 const (
@@ -20,8 +14,6 @@ const (
 
 var (
 	changelogTemplate *template.Template
-
-	headerRegex = regexp.MustCompile(`^# Changelog\n`)
 )
 
 //go:embed changelog.md.tpl
@@ -35,60 +27,6 @@ func init() {
 	}
 }
 
-func UpdateChangelogFile(wt *git.Worktree, newEntry string) error {
-	file, err := wt.Filesystem.OpenFile(ChangelogFile, os.O_RDWR|os.O_CREATE, 0644)
-	if err != nil {
-		return err
-	}
-	defer file.Close()
-
-	content, err := io.ReadAll(file)
-	if err != nil {
-		return err
-	}
-
-	headerIndex := headerRegex.FindIndex(content)
-	if headerIndex == nil && len(content) != 0 {
-		return fmt.Errorf("unexpected format of CHANGELOG.md, header does not match")
-	}
-	if headerIndex != nil {
-		// Remove the header from the content
-		content = content[headerIndex[1]:]
-	}
-
-	err = file.Truncate(0)
-	if err != nil {
-		return err
-	}
-	_, err = file.Seek(0, io.SeekStart)
-	if err != nil {
-		return err
-	}
-
-	_, err = file.Write([]byte(ChangelogHeader + "\n\n" + newEntry))
-	if err != nil {
-		return err
-	}
-
-	_, err = file.Write(content)
-	if err != nil {
-		return err
-	}
-
-	// Close file to make sure it is written to disk.
-	err = file.Close()
-	if err != nil {
-		return err
-	}
-
-	_, err = wt.Add(ChangelogFile)
-	if err != nil {
-		return err
-	}
-
-	return nil
-}
-
 func NewChangelogEntry(commits []AnalyzedCommit, version, link, prefix, suffix string) (string, error) {
 	features := make([]AnalyzedCommit, 0)
 	fixes := make([]AnalyzedCommit, 0)

changelog_test.go

@@ -1,99 +1,15 @@
 package rp
 
 import (
-	"io"
 	"testing"
 
-	"github.com/go-git/go-git/v5"
 	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/apricote/releaser-pleaser/internal/testutils"
 )
 
 func ptr[T any](input T) *T {
 	return &input
 }
 
-func TestUpdateChangelogFile(t *testing.T) {
-	tests := []struct {
-		name            string
-		repoFn          testutils.Repo
-		entry           string
-		expectedContent string
-		wantErr         assert.ErrorAssertionFunc
-	}{
-		{
-			name:            "empty repo",
-			repoFn:          testutils.WithTestRepo(),
-			entry:           "## v1.0.0\n",
-			expectedContent: "# Changelog\n\n## v1.0.0\n",
-			wantErr:         assert.NoError,
-		},
-		{
-			name: "repo with well-formatted changelog",
-			repoFn: testutils.WithTestRepo(testutils.WithCommit("feat: add changelog", testutils.WithFile(ChangelogFile, `# Changelog
-
-## v0.0.1
-
-- Bazzle
-
-## v0.1.0
-
-### Bazuuum
-`))),
-			entry: "## v1.0.0\n\n- Version 1, juhu.\n",
-			expectedContent: `# Changelog
-
-## v1.0.0
-
-- Version 1, juhu.
-
-## v0.0.1
-
-- Bazzle
-
-## v0.1.0
-
-### Bazuuum
-`,
-			wantErr: assert.NoError,
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			repo := tt.repoFn(t)
-			wt, err := repo.Worktree()
-			require.NoError(t, err, "failed to get worktree")
-
-			err = UpdateChangelogFile(wt, tt.entry)
-			if !tt.wantErr(t, err) {
-				return
-			}
-
-			wtStatus, err := wt.Status()
-			require.NoError(t, err, "failed to get worktree status")
-
-			assert.Len(t, wtStatus, 1, "worktree status does not have the expected entry number")
-
-			changelogFileStatus := wtStatus.File(ChangelogFile)
-
-			assert.Equal(t, git.Unmodified, changelogFileStatus.Worktree, "unexpected file status in worktree")
-			assert.Equal(t, git.Added, changelogFileStatus.Staging, "unexpected file status in staging")
-
-			changelogFile, err := wt.Filesystem.Open(ChangelogFile)
-			require.NoError(t, err)
-			defer changelogFile.Close()
-
-			changelogFileContent, err := io.ReadAll(changelogFile)
-			require.NoError(t, err)
-
-			assert.Equal(t, tt.expectedContent, string(changelogFileContent))
-		})
-	}
-}
-
 func Test_NewChangelogEntry(t *testing.T) {
 	type args struct {
 		analyzedCommits []AnalyzedCommit

releaserpleaser.go

@@ -250,11 +250,6 @@ func (rp *ReleaserPleaser) runReconcileReleasePR(ctx context.Context) error {
 	// Info for updaters
 	info := ReleaseInfo{Version: nextVersion, ChangelogEntry: changelogEntry}
 
-	err = UpdateChangelogFile(worktree, changelogEntry)
-	if err != nil {
-		return fmt.Errorf("failed to update changelog file: %w", err)
-	}
-
 	updateFile := func(path string, updaters []Updater) error {
 		file, err := worktree.Filesystem.OpenFile(path, os.O_RDWR, 0)
 		if err != nil {
@@ -297,6 +292,11 @@ func (rp *ReleaserPleaser) runReconcileReleasePR(ctx context.Context) error {
 		return nil
 	}
 
+	err = updateFile(ChangelogFile, []Updater{&ChangelogUpdater{}})
+	if err != nil {
+		return fmt.Errorf("failed to update changelog file: %w", err)
+	}
+
 	for _, path := range rp.extraFiles {
 		_, err = worktree.Filesystem.Stat(path)
 		if err != nil {

updater.go

@@ -1,12 +1,14 @@
 package rp
 
 import (
+	"fmt"
 	"regexp"
 	"strings"
 )
 
 var (
 	GenericUpdaterSemVerRegex   = regexp.MustCompile(`\d+\.\d+\.\d+(-[\w.]+)?(.*x-releaser-pleaser-version)`)
+	ChangelogUpdaterHeaderRegex = regexp.MustCompile(`^# Changelog\n`)
 )
 
 type ReleaseInfo struct {
@@ -26,3 +28,20 @@ func (u *GenericUpdater) UpdateContent(content string, info ReleaseInfo) (string
 
 	return GenericUpdaterSemVerRegex.ReplaceAllString(content, version+"${2}"), nil
 }
+
+type ChangelogUpdater struct{}
+
+func (u *ChangelogUpdater) UpdateContent(content string, info ReleaseInfo) (string, error) {
+	headerIndex := ChangelogUpdaterHeaderRegex.FindStringIndex(content)
+	if headerIndex == nil && len(content) != 0 {
+		return "", fmt.Errorf("unexpected format of CHANGELOG.md, header does not match")
+	}
+	if headerIndex != nil {
+		// Remove the header from the content
+		content = content[headerIndex[1]:]
+	}
+
+	content = ChangelogHeader + "\n\n" + info.ChangelogEntry + content
+
+	return content, nil
+}

updater_test.go

@@ -72,3 +72,58 @@ func TestGenericUpdater_UpdateContent(t *testing.T) {
 		})
 	}
 }
+
+func TestChangelogUpdater_UpdateContent(t *testing.T) {
+	updater := &ChangelogUpdater{}
+
+	tests := []updaterTestCase{
+		{
+			name:    "empty file",
+			content: "",
+			info:    ReleaseInfo{ChangelogEntry: "## v1.0.0\n"},
+			want:    "# Changelog\n\n## v1.0.0\n",
+			wantErr: assert.NoError,
+		},
+		{
+			name: "well-formatted changelog",
+			content: `# Changelog
+
+## v0.0.1
+
+- Bazzle
+
+## v0.1.0
+
+### Bazuuum
+`,
+			info: ReleaseInfo{ChangelogEntry: "## v1.0.0\n\n- Version 1, juhu.\n"},
+			want: `# Changelog
+
+## v1.0.0
+
+- Version 1, juhu.
+
+## v0.0.1
+
+- Bazzle
+
+## v0.1.0
+
+### Bazuuum
+`,
+			wantErr: assert.NoError,
+		},
+		{
+			name:    "error on invalid header",
+			content: "What even is this file?",
+			info:    ReleaseInfo{ChangelogEntry: "## v1.0.0\n\n- Version 1, juhu.\n"},
+			want:    "",
+			wantErr: assert.Error,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			runUpdaterTest(t, updater, tt)
+		})
+	}
+}