commit 2060af6a7869d24e23b80dcda907bdc417d70e89
Author: Micheal Wilkinson <micheal.wilkinson@createfuture.com>
Date:   Fri Mar 20 18:22:45 2026 +0000

    test(releaseprep): add failing migration test suite

diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..41c7b56
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,13 @@
+module git.hrafn.xyz/aether/vociferate
+
+go 1.26
+
+toolchain go1.26.1
+
+require github.com/stretchr/testify v1.10.0
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..713a0b4
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,10 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
+github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/internal/releaseprep/releaseprep_test.go b/internal/releaseprep/releaseprep_test.go
new file mode 100644
index 0000000..5b2af8b
--- /dev/null
+++ b/internal/releaseprep/releaseprep_test.go
@@ -0,0 +1,166 @@
+package releaseprep_test
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"git.hrafn.xyz/aether/vociferate/internal/releaseprep"
+	"github.com/stretchr/testify/require"
+	"github.com/stretchr/testify/suite"
+)
+
+type PrepareSuite struct {
+	suite.Suite
+	rootDir string
+}
+
+func TestPrepareSuite(t *testing.T) {
+	suite.Run(t, new(PrepareSuite))
+}
+
+func (s *PrepareSuite) SetupTest() {
+	s.rootDir = s.T().TempDir()
+	versionDir := filepath.Join(s.rootDir, "internal", "releaseprep", "version")
+	require.NoError(s.T(), os.MkdirAll(versionDir, 0o755))
+
+	require.NoError(s.T(), os.WriteFile(
+		filepath.Join(versionDir, "version.go"),
+		[]byte("package version\n\nconst String = \"1.1.6\"\n"),
+		0o644,
+	))
+
+	require.NoError(s.T(), os.WriteFile(
+		filepath.Join(s.rootDir, "changelog.md"),
+		[]byte("# Changelog\n\n## [Unreleased]\n\n### Breaking\n\n### Added\n\n- New thing.\n\n### Fixed\n\n- Old thing.\n\n## [1.1.6] - 2017-12-20\n\n### Fixed\n\n- Historical note.\n"),
+		0o644,
+	))
+}
+
+func (s *PrepareSuite) TestPrepare_UpdatesVersionAndPromotesUnreleasedNotes() {
+	err := releaseprep.Prepare(s.rootDir, "v1.1.7", "2026-03-20", releaseprep.Options{})
+
+	require.NoError(s.T(), err)
+
+	versionBytes, err := os.ReadFile(filepath.Join(s.rootDir, "internal", "releaseprep", "version", "version.go"))
+	require.NoError(s.T(), err)
+	require.Equal(s.T(), "package version\n\nconst String = \"1.1.7\"\n", string(versionBytes))
+
+	changelogBytes, err := os.ReadFile(filepath.Join(s.rootDir, "changelog.md"))
+	require.NoError(s.T(), err)
+	require.Equal(s.T(), "# Changelog\n\n## [Unreleased]\n\n## [1.1.7] - 2026-03-20\n\n### Breaking\n\n### Added\n\n- New thing.\n\n### Fixed\n\n- Old thing.\n\n## [1.1.6] - 2017-12-20\n\n### Fixed\n\n- Historical note.\n", string(changelogBytes))
+}
+
+func (s *PrepareSuite) TestPrepare_ReturnsErrorWhenUnreleasedSectionMissing() {
+	require.NoError(s.T(), os.WriteFile(
+		filepath.Join(s.rootDir, "changelog.md"),
+		[]byte("# Changelog\n\n## [1.1.6] - 2017-12-20\n"),
+		0o644,
+	))
+
+	err := releaseprep.Prepare(s.rootDir, "1.1.7", "2026-03-20", releaseprep.Options{})
+
+	require.ErrorContains(s.T(), err, "unreleased section")
+}
+
+func (s *PrepareSuite) TestPrepare_ReturnsErrorWhenUnreleasedSectionIsEmpty() {
+	require.NoError(s.T(), os.WriteFile(
+		filepath.Join(s.rootDir, "changelog.md"),
+		[]byte("# Changelog\n\n## [Unreleased]\n\n## [1.1.6] - 2017-12-20\n"),
+		0o644,
+	))
+
+	err := releaseprep.Prepare(s.rootDir, "1.1.7", "2026-03-20", releaseprep.Options{})
+
+	require.ErrorContains(s.T(), err, "unreleased section is empty")
+}
+
+func (s *PrepareSuite) TestRecommendedTag_UsesMinorBumpWhenAddedEntriesExist() {
+	tag, err := releaseprep.RecommendedTag(s.rootDir, releaseprep.Options{})
+
+	require.NoError(s.T(), err)
+	require.Equal(s.T(), "v1.2.0", tag)
+}
+
+func (s *PrepareSuite) TestRecommendedTag_UsesPatchBumpForFixOnlyChanges() {
+	require.NoError(s.T(), os.WriteFile(
+		filepath.Join(s.rootDir, "changelog.md"),
+		[]byte("# Changelog\n\n## [Unreleased]\n\n### Fixed\n\n- Patch note.\n\n## [1.1.6] - 2017-12-20\n"),
+		0o644,
+	))
+
+	tag, err := releaseprep.RecommendedTag(s.rootDir, releaseprep.Options{})
+
+	require.NoError(s.T(), err)
+	require.Equal(s.T(), "v1.1.7", tag)
+}
+
+func (s *PrepareSuite) TestRecommendedTag_UsesMajorBumpWhenRemovedEntriesExist() {
+	require.NoError(s.T(), os.WriteFile(
+		filepath.Join(s.rootDir, "changelog.md"),
+		[]byte("# Changelog\n\n## [Unreleased]\n\n### Removed\n\n- Breaking removal.\n\n## [1.1.6] - 2017-12-20\n"),
+		0o644,
+	))
+
+	tag, err := releaseprep.RecommendedTag(s.rootDir, releaseprep.Options{})
+
+	require.NoError(s.T(), err)
+	require.Equal(s.T(), "v2.0.0", tag)
+}
+
+func (s *PrepareSuite) TestRecommendedTag_UsesMajorBumpWhenBreakingEntriesExist() {
+	require.NoError(s.T(), os.WriteFile(
+		filepath.Join(s.rootDir, "changelog.md"),
+		[]byte("# Changelog\n\n## [Unreleased]\n\n### Breaking\n\n- Changed API contract.\n\n### Changed\n\n- Updated defaults.\n\n## [1.1.6] - 2017-12-20\n"),
+		0o644,
+	))
+
+	tag, err := releaseprep.RecommendedTag(s.rootDir, releaseprep.Options{})
+
+	require.NoError(s.T(), err)
+	require.Equal(s.T(), "v2.0.0", tag)
+}
+
+func (s *PrepareSuite) TestPrepare_UsesCustomVersionFileAndPattern() {
+	customVersionFile := filepath.Join("custom", "VERSION.txt")
+	require.NoError(s.T(), os.MkdirAll(filepath.Join(s.rootDir, "custom"), 0o755))
+	require.NoError(s.T(), os.WriteFile(
+		filepath.Join(s.rootDir, customVersionFile),
+		[]byte("VERSION=1.1.6\n"),
+		0o644,
+	))
+
+	err := releaseprep.Prepare(s.rootDir, "1.1.8", "2026-03-20", releaseprep.Options{
+		VersionFile:    customVersionFile,
+		VersionPattern: `VERSION=([^\n]+)`,
+	})
+
+	require.NoError(s.T(), err)
+
+	versionBytes, err := os.ReadFile(filepath.Join(s.rootDir, customVersionFile))
+	require.NoError(s.T(), err)
+	require.Equal(s.T(), "VERSION=1.1.8\n", string(versionBytes))
+}
+
+func (s *PrepareSuite) TestRecommendedTag_UsesCustomVersionFileAndPattern() {
+	customVersionFile := filepath.Join("custom", "VERSION.txt")
+	require.NoError(s.T(), os.MkdirAll(filepath.Join(s.rootDir, "custom"), 0o755))
+	require.NoError(s.T(), os.WriteFile(
+		filepath.Join(s.rootDir, customVersionFile),
+		[]byte("VERSION=2.3.4\n"),
+		0o644,
+	))
+	require.NoError(s.T(), os.WriteFile(
+		filepath.Join(s.rootDir, "changelog.md"),
+		[]byte("# Changelog\n\n## [Unreleased]\n\n### Added\n\n- Feature.\n\n## [2.3.4] - 2026-03-10\n"),
+		0o644,
+	))
+
+	tag, err := releaseprep.RecommendedTag(s.rootDir, releaseprep.Options{
+		VersionFile:    customVersionFile,
+		VersionPattern: `VERSION=([^\n]+)`,
+	})
+
+	require.NoError(s.T(), err)
+	require.Equal(s.T(), "v2.4.0", tag)
+}