refactor: move things to packages

internal/updater/changelog.go

@@ -0,0 +1,32 @@
+package updater
+
+import (
+	"fmt"
+	"regexp"
+)
+
+const (
+	ChangelogHeader = "# Changelog"
+	ChangelogFile   = "CHANGELOG.md"
+)
+
+var (
+	ChangelogUpdaterHeaderRegex = regexp.MustCompile(`^# Changelog\n`)
+)
+
+func Changelog(info ReleaseInfo) Updater {
+	return func(content string) (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
+	}
+}

internal/updater/changelog_test.go

@@ -0,0 +1,60 @@
+package updater
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestChangelogUpdater_UpdateContent(t *testing.T) {
+	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, Changelog, tt)
+		})
+	}
+}

internal/updater/generic.go

@@ -0,0 +1,17 @@
+package updater
+
+import (
+	"regexp"
+	"strings"
+)
+
+var GenericUpdaterSemVerRegex = regexp.MustCompile(`\d+\.\d+\.\d+(-[\w.]+)?(.*x-releaser-pleaser-version)`)
+
+func Generic(info ReleaseInfo) Updater {
+	return func(content string) (string, error) {
+		// We strip the "v" prefix to avoid adding/removing it from the users input.
+		version := strings.TrimPrefix(info.Version, "v")
+
+		return GenericUpdaterSemVerRegex.ReplaceAllString(content, version+"${2}"), nil
+	}
+}

internal/updater/generic_test.go

@@ -0,0 +1,53 @@
+package updater
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGenericUpdater_UpdateContent(t *testing.T) {
+	tests := []updaterTestCase{
+		{
+			name:    "single line",
+			content: "v1.0.0 // x-releaser-pleaser-version",
+			info: ReleaseInfo{
+				Version: "v1.2.0",
+			},
+			want:    "v1.2.0 // x-releaser-pleaser-version",
+			wantErr: assert.NoError,
+		},
+		{
+			name:    "multiline line",
+			content: "Foooo\n\v1.2.0\nv1.0.0 // x-releaser-pleaser-version\n",
+			info: ReleaseInfo{
+				Version: "v1.2.0",
+			},
+			want:    "Foooo\n\v1.2.0\nv1.2.0 // x-releaser-pleaser-version\n",
+			wantErr: assert.NoError,
+		},
+		{
+			name:    "invalid existing version",
+			content: "1.0 // x-releaser-pleaser-version",
+			info: ReleaseInfo{
+				Version: "v1.2.0",
+			},
+			want:    "1.0 // x-releaser-pleaser-version",
+			wantErr: assert.NoError,
+		},
+		{
+			name:    "complicated line",
+			content: "version: v1.2.0-alpha.1 => Awesome, isnt it? x-releaser-pleaser-version foobar",
+			info: ReleaseInfo{
+				Version: "v1.2.0",
+			},
+			want:    "version: v1.2.0 => Awesome, isnt it? x-releaser-pleaser-version foobar",
+			wantErr: assert.NoError,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			runUpdaterTest(t, Generic, tt)
+		})
+	}
+}

internal/updater/updater.go

@@ -0,0 +1,19 @@
+package updater
+
+type ReleaseInfo struct {
+	Version        string
+	ChangelogEntry string
+}
+
+type Updater func(string) (string, error)
+
+type NewUpdater func(ReleaseInfo) Updater
+
+func WithInfo(info ReleaseInfo, constructors ...NewUpdater) []Updater {
+	updaters := make([]Updater, 0, len(constructors))
+	for _, constructor := range constructors {
+		updaters = append(updaters, constructor(info))
+	}
+
+	return updaters
+}

internal/updater/updater_test.go

@@ -0,0 +1,26 @@
+package updater
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type updaterTestCase struct {
+	name    string
+	content string
+	info    ReleaseInfo
+	want    string
+	wantErr assert.ErrorAssertionFunc
+}
+
+func runUpdaterTest(t *testing.T, constructor NewUpdater, tt updaterTestCase) {
+	t.Helper()
+
+	got, err := constructor(tt.info)(tt.content)
+	if !tt.wantErr(t, err, fmt.Sprintf("Updater(%v, %v)", tt.content, tt.info)) {
+		return
+	}
+	assert.Equalf(t, tt.want, got, "Updater(%v, %v)", tt.content, tt.info)
+}