migrate_test.v

1//! Migration tests, run against a fixture made by the Koh 2 binary itself.2//!3//! The fixture is why these are worth having: it is not a guess at Koh 2's4//! format, it is the format, including the inlined small files and the object5//! store. When `koh` (Koh 2) is not on the machine these tests skip rather6//! than pretend.78module migrate910import json11import os12import src.events13import src.history14import src.snapshot15import src.storage1617struct Fixture {18	dir     string19	first   string20	second  string21	message string22}2324fn koh2_binary() ?string {25	path := os.find_abs_path_of_executable('koh') or { return none }26	return path27}2829fn sh(dir string, command string) !string {30	result := os.execute('cd ${dir} && ${command}')31	if result.exit_code != 0 {32		return error('${command} failed: ${result.output}')33	}34	return result.output35}3637fn make_fixture(koh2 string) !Fixture {38	dir := os.join_path(os.temp_dir(), 'koh3_migrate_${os.getpid()}')39	os.rmdir_all(dir) or {}40	os.mkdir_all(dir, os.MkdirParams{})!41	sh(dir, '${koh2} init')!42	// One file big enough for the object store, one small enough to be inlined.43	os.write_file(os.join_path(dir, 'big.txt'), 'x'.repeat(700))!44	os.write_file(os.join_path(dir, 'small.txt'), 'tiny\n')!45	sh(dir, '${koh2} save "first save"')!46	sh(dir, '${koh2} checkpoint "before something"')!47	os.write_file(os.join_path(dir, 'big.txt'), 'y'.repeat(700))!48	sh(dir, '${koh2} save "second save"')!4950	// Identify the first save by its message: koh2 timestamps are whole seconds,51	// so saves made in a row share one, and a filename is a hash. The head comes52	// from Koh 2's own state for the same reason.53	mut first := ''54	for name in os.ls(os.join_path(dir, '.koh', 'snapshots'))! {55		if !name.ends_with('.json') {56			continue57		}58		record :=59			json.decode(Manifest, os.read_file(os.join_path(dir, '.koh', 'snapshots', name))!)!60		if record.message == 'first save' {61			first = record.id62		}63	}64	assert first != ''65	return Fixture{66		dir:     dir67		first:   first68		second:  koh2_head(dir)69		message: 'first save'70	}71}7273// koh2_head reads the lane head Koh 2 recorded.74fn koh2_head(dir string) string {75	db := storage.connect(os.join_path(dir, '.koh', 'koh.db'), 1000) or { return '' }76	defer {77		db.close()78	}79	mut stmt := db.prepare('SELECT value FROM state WHERE key = ?') or { return '' }80	defer {81		stmt.finalize()82	}83	stmt.bind_text(1, 'head_main') or { return '' }84	if stmt.step() or { return '' } {85		return stmt.text(0)86	}87	return ''88}8990fn test_migrating_a_koh2_repo_keeps_every_save_exactly() {91	koh2 := koh2_binary() or { return }92	fixture := make_fixture(koh2)!93	defer {94		os.rmdir_all(fixture.dir) or {}95	}96	// Flag the first save, so a save-level flag has to become an event.97	sh(fixture.dir, '${koh2} flag ${fixture.first} --reason "sketchy"')!9899	// What the manifests say, read independently of the migration.100	mut manifests := map[string][]string{}101	for name in os.ls(os.join_path(fixture.dir, '.koh', 'snapshots'))! {102		if !name.ends_with('.json') {103			continue104		}105		record := json.decode(Manifest,106			os.read_file(os.join_path(fixture.dir, '.koh', 'snapshots', name))!)!107		mut files := []string{}108		for file in record.files {109			files << '${file.path} ${bare_hash(file.hash)}'110		}111		manifests[record.id] = files112	}113114	report := run(fixture.dir, default_lane)!115	// The fixture lives on main, because that is the lane koh2 starts on.116	assert report.lane == 'main'117	assert report.saves == 3118	assert report.checkpoints == 1119	assert report.flags == 1120	assert report.objects >= 3121122	// The swap happened: `.koh` is a file now and the old data is archived.123	assert os.is_file(os.join_path(fixture.dir, '.koh'))124	assert os.is_dir(os.join_path(fixture.dir, '.koh-v2'))125	assert os.is_file(os.join_path(fixture.dir, '.kohignore'))126127	store := storage.open(fixture.dir)!128	defer {129		store.close()130	}131	// Every save kept its ID, its files and their hashes.132	assert history.save_count(store)! == 3133	for id, expected in manifests {134		save := history.by_id(store, id) or {135			assert false, 'save ${id} did not survive the migration'136			return137		}138		assert save.machine == 'koh2'139		mut actual := []string{}140		for file in history.files_of(store, id)! {141			actual << '${file.path} ${file.hash}'142			// Every object is present and hashes back to its key.143			if _ := store.get_object(file.hash) {144			} else {145				assert false, 'object ${file.hash} is missing or corrupt'146			}147		}148		assert actual == expected149	}150	// The checkpoint mark and the parent chain came across.151	middle := history.by_id(store, fixture.first) or { panic('the first save did not survive') }152	assert (history.head(store) or { panic('no head after migrating') }).id == fixture.second153	assert middle.message == 'first save'154155	// The flag became an event, and the working tree is exactly what Koh 3156	// expects once the carried ignore file is saved.157	assert events.flag_state(store, fixture.first)!.flagged158	assert events.flag_state(store, fixture.first)!.reason == 'sketchy'159	entries := snapshot.walk(store, fixture.dir, snapshot.load(fixture.dir))!160	mut changed := []string{}161	head_files := snapshot.index_files(history.files_of(store, fixture.second)!)162	for entry in entries {163		if entry.path !in head_files {164			changed << entry.path165		} else if head_files[entry.path].hash != entry.hash {166			changed << entry.path167		}168	}169	// The only difference is the ignore file Koh 3 just carried to the root.170	assert changed == ['.kohignore']171}172173fn test_migrate_refuses_a_tree_that_does_not_match_the_last_save() {174	koh2 := koh2_binary() or { return }175	fixture := make_fixture(koh2)!176	defer {177		os.rmdir_all(fixture.dir) or {}178	}179	os.write_file(os.join_path(fixture.dir, 'big.txt'), 'unsaved change\n')!180	if _ := run(fixture.dir, default_lane) {181		assert false, 'a dirty tree must be refused'182	} else {183		assert err.msg().contains('save with koh2 first')184	}185	// Nothing was touched: still a Koh 2 repo, no archive, no staging file.186	assert os.is_dir(os.join_path(fixture.dir, '.koh'))187	assert !os.exists(os.join_path(fixture.dir, '.koh-v2'))188	assert !os.exists(os.join_path(fixture.dir, staging_file))189}