exchange_test.v

1//! Two-machine tests: two repos and one folder remote standing in for the Mac2//! and the PC. This is where offer, steal and combine are actually proven —3//! the folder backend exists so these run offline.45module exchange67import os8import src.events9import src.history10import src.remote11import src.snapshot12import src.storage1314// Machines keep their repo in a folder of the same NAME, because the remote key15// is the folder's name; that is what makes them the same repo to the remote.16fn machine(name string) !string {17	dir := os.join_path(os.temp_dir(), 'koh3_sync_${os.getpid()}_${name}', 'proj')18	os.rmdir_all(os.dir(dir)) or {}19	os.mkdir_all(dir, os.MkdirParams{})!20	return dir21}2223fn scratch(name string) !string {24	dir := os.join_path(os.temp_dir(), 'koh3_sync_${os.getpid()}_${name}')25	os.rmdir_all(dir) or {}26	os.mkdir_all(dir, os.MkdirParams{})!27	return dir28}2930fn open_repo(dir string) !storage.Store {31	mut store := storage.create(dir)!32	os.write_file(os.join_path(dir, '.kohignore'), '*.log\n')!33	return store34}3536fn put(root string, rel string, text string) ! {37	full := os.join_path(root, rel)38	os.mkdir_all(os.dir(full), os.MkdirParams{})!39	os.write_file(full, text)!40}4142fn make_save(store &storage.Store, message string) !history.Save {43	return history.save_worktree(store, store.root, snapshot.load(store.root), history.SaveInput{44		message: message45	})!46}4748fn offer_now(store &storage.Store, mut backend remote.Backend) !OfferReport {49	return offer(store, mut backend)!50}5152fn steal_now(store &storage.Store, mut backend remote.Backend) !StealReport {53	return steal(store, mut backend, StealOptions{54		theirs: true55	})!56}5758fn test_first_offer_publishes_the_whole_line() {59	base := scratch('first')!60	defer {61		os.rmdir_all(base) or {}62	}63	mut a := open_repo(machine('first_a')!)!64	defer {65		a.close()66	}67	put(a.root, 'a.txt', 'one\n')!68	make_save(a, 'first')!69	put(a.root, 'a.txt', 'two\n')!70	make_save(a, 'second')!71	mut backend := remote.new_folder(os.join_path(base, 'remote'))!7273	report := offer_now(a, mut backend)!74	assert report.repo == 'proj'75	assert report.saves == 276	assert report.objects >= 277	assert backend.get(head_key('proj'))!.found78	assert backend.list('proj/saves')!.len == 27980	// A second offer with nothing new uploads nothing and still succeeds.81	again := offer_now(a, mut backend)!82	assert again.saves == 083}8485fn test_the_repo_name_is_remembered_and_head_offered() {86	base := scratch('remember')!87	defer {88		os.rmdir_all(base) or {}89	}90	mut a := open_repo(machine('remember_a')!)!91	defer {92		a.close()93	}94	put(a.root, 'a.txt', 'one\n')!95	make_save(a, 'first')!96	mut backend := remote.new_folder(os.join_path(base, 'remote'))!97	offer_now(a, mut backend)!98	assert a.state('remote_repo') or { '' } == 'proj'99	assert backend.get(head_key('proj'))!.body.bytestr() == head_of(a).id100	// Offer's step 3: the new remote head is recorded in state.101	assert a.state('remote_head') or { '' } == head_of(a).id102103	// A second offer, with the remote already holding our head, must not104	// refuse: the name is remembered, so the remote is ours.105	put(a.root, 'a.txt', 'two\n')!106	make_save(a, 'second')!107	offer_now(a, mut backend)!108	assert backend.get(head_key('proj'))!.body.bytestr() == head_of(a).id109}110111fn test_steal_fast_forwards_a_machine_that_has_nothing_of_its_own() {112	base := scratch('forward')!113	defer {114		os.rmdir_all(base) or {}115	}116	mut backend := remote.new_folder(os.join_path(base, 'remote'))!117	mut a := open_repo(machine('fwd_a')!)!118	defer {119		a.close()120	}121	put(a.root, 'a.txt', 'from A\n')!122	make_save(a, 'A writes')!123	offer_now(a, mut backend)!124125	// B starts empty and pulls the whole repo.126	mut b := open_repo(machine('fwd_b')!)!127	defer {128		b.close()129	}130	fetched := fetch_repo(mut backend, 'proj')!131	b.begin()!132	write_fetched(b, fetched)!133	history.set_head(b, fetched.head)!134	b.commit()!135	snapshot.restore_files(b, b.root, snapshot.load(b.root), history.files_of(b, fetched.head)!, [])!136	assert os.read_file(os.join_path(b.root, 'a.txt'))! == 'from A\n'137	assert head_of(b).id == fetched.head138}139140// A machine that is only ahead has nothing to combine: stealing must leave its141// saves, and their IDs, exactly where they are.142fn test_steal_while_only_ahead_leaves_the_line_alone() {143	base := scratch('ahead')!144	defer {145		os.rmdir_all(base) or {}146	}147	mut backend := remote.new_folder(os.join_path(base, 'remote'))!148	mut a := open_repo(machine('ahead_a')!)!149	defer {150		a.close()151	}152	put(a.root, 'a.txt', 'one\n')!153	make_save(a, 'offered')!154	offer_now(a, mut backend)!155	put(a.root, 'a.txt', 'two\n')!156	ahead := make_save(a, 'not offered yet')!157	report := steal_now(a, mut backend)!158	assert report.replayed == 0159	assert head_of(a).id == ahead.id160	// Nothing was restored, so nothing is left marked as half-restored.161	assert !snapshot.restore_pending(a)162	assert history.all_saves(a)!.len == 2163	offer_now(a, mut backend)!164	assert backend.get(head_key('proj'))!.body.bytestr() == ahead.id165}166167// A link is invisible to the walk, so a tree holding one is clean; the files168// a steal brings in must still never land in the folder it points at.169fn test_steal_never_writes_through_a_symlinked_folder() {170	base := scratch('steal_link')!171	defer {172		os.rmdir_all(base) or {}173	}174	mut backend := remote.new_folder(os.join_path(base, 'remote'))!175	mut a := open_repo(machine('steal_link_a')!)!176	defer {177		a.close()178	}179	mut b := open_repo(machine('steal_link_b')!)!180	defer {181		b.close()182	}183	put(a.root, 'a.txt', 'one\n')!184	make_save(a, 'first')!185	offer_now(a, mut backend)!186	join(b, mut backend)!187	outside := os.join_path(base, 'outside')188	put(outside, 'a.md', 'precious\n')!189	os.symlink(outside, os.join_path(b.root, 'docs'))!190	put(a.root, 'docs/a.md', 'from A\n')!191	make_save(a, 'A adds docs')!192	offer_now(a, mut backend)!193	head_before := head_of(b).id194	if _ := steal_now(b, mut backend) {195		assert false, 'a steal writing through a symlinked folder must refuse'196	} else {197		assert err.msg().contains('docs')198	}199	assert os.read_file(os.join_path(outside, 'a.md'))! == 'precious\n'200	assert head_of(b).id == head_before201}202203// A steal onto a half-restored tree would replay it as somebody's work.204fn test_steal_refuses_after_a_restore_cut_short() {205	base := scratch('steal_cut')!206	defer {207		os.rmdir_all(base) or {}208	}209	mut backend := remote.new_folder(os.join_path(base, 'remote'))!210	mut a := open_repo(machine('steal_cut_a')!)!211	defer {212		a.close()213	}214	put(a.root, 'a.txt', 'one\n')!215	make_save(a, 'first')!216	offer_now(a, mut backend)!217	a.set_state('restoring', 'yes')!218	if _ := steal_now(a, mut backend) {219		assert false, 'steal must refuse while a restore is unfinished'220	} else {221		assert err.msg().contains('koh revert')222	}223}224225// A replayed save keeps its original time but sits on a newer parent, so a226// clone cannot order saves by time.227fn test_a_clone_imports_parents_before_children() {228	base := scratch('clone_order')!229	defer {230		os.rmdir_all(base) or {}231	}232	mut backend := remote.new_folder(os.join_path(base, 'remote'))!233	mut a := open_repo(machine('order_a')!)!234	defer {235		a.close()236	}237	put(a.root, 'a.txt', 'one\n')!238	parent := make_save(a, 'parent')!239	child := history.save_tree(a, '', history.files_of(a, parent.id)!, history.SaveInput{240		message:    'replayed, older than its parent'241		created_at: parent.created_at - 3600242	})!243	offer_now(a, mut backend)!244	mut b := open_repo(machine('order_b')!)!245	defer {246		b.close()247	}248	join(b, mut backend)!249	assert head_of(b).id == child.id250}251252// A chmod is unsaved work too: a steal would restore the old mode over it.253fn test_steal_refuses_an_unsaved_executable_bit_change() {254	base := scratch('chmod')!255	defer {256		os.rmdir_all(base) or {}257	}258	mut backend := remote.new_folder(os.join_path(base, 'remote'))!259	mut a := open_repo(machine('chmod_a')!)!260	defer {261		a.close()262	}263	put(a.root, 'run.sh', 'echo hi\n')!264	make_save(a, 'script')!265	offer_now(a, mut backend)!266	os.chmod(os.join_path(a.root, 'run.sh'), 0o755)!267	if _ := steal_now(a, mut backend) {268		assert false, 'a chmod-only change should make the tree dirty'269	} else {270		assert err.msg() == dirty_tree271	}272}273274fn test_divergence_without_clashes_keeps_both_machines_work() {275	base := scratch('diverge')!276	defer {277		os.rmdir_all(base) or {}278	}279	mut backend := remote.new_folder(os.join_path(base, 'remote'))!280	mut a := open_repo(machine('div_a')!)!281	defer {282		a.close()283	}284	mut b := open_repo(machine('div_b')!)!285	defer {286		b.close()287	}288	put(a.root, 'shared.txt', 'base\n')!289	make_save(a, 'base')!290	offer_now(a, mut backend)!291292	// B joins, then both machines change a different file.293	join(b, mut backend)!294	put(a.root, 'fromA.txt', 'A\n')!295	make_save(a, 'A adds a file')!296	put(b.root, 'fromB.txt', 'B\n')!297	make_save(b, 'B adds a file')!298	offer_now(a, mut backend)!299300	// B's offer is refused: the remote has moved on.301	if _ := offer_now(b, mut backend) {302		assert false, 'offering on top of unknown remote saves should be refused'303	} else {304		assert err.msg().contains('run koh steal')305	}306307	report := steal_now(b, mut backend)!308	assert !report.forward309	assert report.replayed == 1310	assert report.clashes.len == 0311	// Both files are on B's line now, and on disk.312	assert os.read_file(os.join_path(b.root, 'fromA.txt'))! == 'A\n'313	assert os.read_file(os.join_path(b.root, 'fromB.txt'))! == 'B\n'314	assert os.read_file(os.join_path(b.root, 'shared.txt'))! == 'base\n'315	// B's own save was replayed, not erased.316	mut saw_replay := false317	for save in history.all_saves(b)! {318		if save.replayed_from != '' {319			saw_replay = true320		}321	}322	assert saw_replay323	// And the remote now has B's work too.324	offer_now(b, mut backend)!325	line_head := backend.get(head_key('proj'))!.body.bytestr().trim_space()326	assert line_head == head_of(b).id327}328329// An agent that edits a file and then undoes the edit leaves no net change, so330// the file is not a clash when the other machine changed it. Replaying the331// edit itself must not stop the steal: the remote's version simply stands.332// Likewise a file both machines ended up changing the same way.333fn test_a_local_change_undone_does_not_block_a_combine() {334	base := scratch('undone')!335	defer {336		os.rmdir_all(base) or {}337	}338	mut backend := remote.new_folder(os.join_path(base, 'remote'))!339	mut a := open_repo(machine('undone_a')!)!340	defer {341		a.close()342	}343	mut b := open_repo(machine('undone_b')!)!344	defer {345		b.close()346	}347	put(a.root, 'f.txt', 'base\n')!348	put(a.root, 'g.txt', 'base\n')!349	make_save(a, 'base')!350	offer_now(a, mut backend)!351	join(b, mut backend)!352353	put(a.root, 'f.txt', 'from A\n')!354	put(a.root, 'g.txt', 'same\n')!355	make_save(a, 'A edits both')!356	offer_now(a, mut backend)!357358	put(b.root, 'f.txt', 'tried on B\n')!359	put(b.root, 'g.txt', 'first try\n')!360	tried := make_save(b, 'B tries')!361	put(b.root, 'f.txt', 'base\n')!362	put(b.root, 'g.txt', 'same\n')!363	put(b.root, 'h.txt', 'B\n')!364	undone := make_save(b, 'B undoes f, lands on the same g, adds h')!365366	report := steal_now(b, mut backend)!367	assert report.clashes.len == 0368	assert os.read_file(os.join_path(b.root, 'f.txt'))! == 'from A\n'369	assert os.read_file(os.join_path(b.root, 'g.txt'))! == 'same\n'370	assert os.read_file(os.join_path(b.root, 'h.txt'))! == 'B\n'371	// "B tries" only touched files A changed, so it has nothing left to372	// replay; the second save carries h.txt. Both originals stay in history.373	assert report.replayed == 1374	assert head_of(b).replayed_from == undone.id375	ids := history.all_saves(b)!.map(it.id)376	assert tried.id in ids && undone.id in ids377	assert history.files_of(b, tried.id)!.any(it.path == 'f.txt')378}379380// A person deciding a clash may take minutes; the question must come before381// the write lock, or every agent's save on this repo waits and then fails.382fn test_clash_questions_are_asked_before_the_write_lock() {383	base := scratch('ask_unlocked')!384	defer {385		os.rmdir_all(base) or {}386	}387	mut backend := remote.new_folder(os.join_path(base, 'remote'))!388	mut a := open_repo(machine('ask_a')!)!389	defer {390		a.close()391	}392	mut b := open_repo(machine('ask_b')!)!393	defer {394		b.close()395	}396	put(a.root, 'same.txt', 'base\n')!397	make_save(a, 'base')!398	offer_now(a, mut backend)!399	join(b, mut backend)!400	put(a.root, 'same.txt', 'A version\n')!401	make_save(a, 'A edits same')!402	offer_now(a, mut backend)!403	put(b.root, 'same.txt', 'B version\n')!404	make_save(b, 'B edits same')!405	root := b.root406	// An agent saves while the person is still choosing.407	if _ := steal(b, mut backend, StealOptions{408		ask: fn [root] (clash Clash) Side {409			other := storage.open(root) or { panic(err) }410			defer {411				other.close()412			}413			os.write_file(os.join_path(root, 'agent.txt'), 'saved meanwhile\n') or { panic(err) }414			history.save_worktree(other, root, snapshot.load(root), history.SaveInput{415				message: 'agent saves during the question'416			}) or { panic('steal held the write lock while asking: ${err}') }417			return .mine418		}419	})420	{421		assert false, 'a steal whose line moved during the question must refuse'422	} else {423		assert err.msg().contains('changed while')424	}425	// The agent's save is still head, and a second steal combines it too.426	assert head_of(b).message == 'agent saves during the question'427	report := steal(b, mut backend, StealOptions{428		mine: true429	})!430	assert report.kept_mine == 1431	assert os.read_file(os.join_path(b.root, 'agent.txt'))! == 'saved meanwhile\n'432	assert os.read_file(os.join_path(b.root, 'same.txt'))! == 'B version\n'433}434435fn test_clashing_files_are_chosen_one_at_a_time() {436	base := scratch('clash')!437	defer {438		os.rmdir_all(base) or {}439	}440	mut backend := remote.new_folder(os.join_path(base, 'remote'))!441	mut a := open_repo(machine('clash_a')!)!442	defer {443		a.close()444	}445	mut b := open_repo(machine('clash_b')!)!446	defer {447		b.close()448	}449	put(a.root, 'same.txt', 'base\n')!450	put(a.root, 'other.txt', 'quiet\n')!451	make_save(a, 'base')!452	offer_now(a, mut backend)!453	join(b, mut backend)!454455	// Both machines edit the same file, differently.456	put(a.root, 'same.txt', 'A version\n')!457	make_save(a, 'A edits same')!458	offer_now(a, mut backend)!459	put(b.root, 'same.txt', 'B version\n')!460	make_save(b, 'B edits same')!461462	// Without a decision, steal refuses and says which files clash.463	if _ := steal(b, mut backend, StealOptions{}) {464		assert false, 'an undecided clash must be refused'465	} else {466		assert err.msg().contains('--mine') || err.msg().contains('--theirs')467	}468	assert find_clashes(history.files_of(b, head_of(b).id)!, history.files_of(b, head_of(b).id)!, history.files_of(b,469		head_of(b).id)!).len == 0470471	// Choosing the remote's version ends with A's content.472	report := steal_now(b, mut backend)!473	assert report.clashes == ['same.txt']474	assert report.kept_mine == 0475	assert report.kept_versions == ['same.txt:${report.previous_head}']476	assert os.read_file(os.join_path(b.root, 'same.txt'))! == 'A version\n'477	assert os.read_file(os.join_path(b.root, 'other.txt'))! == 'quiet\n'478}479480fn test_choosing_mine_keeps_the_local_version() {481	base := scratch('mine')!482	defer {483		os.rmdir_all(base) or {}484	}485	mut backend := remote.new_folder(os.join_path(base, 'remote'))!486	mut a := open_repo(machine('mine_a')!)!487	defer {488		a.close()489	}490	mut b := open_repo(machine('mine_b')!)!491	defer {492		b.close()493	}494	put(a.root, 'same.txt', 'base\n')!495	make_save(a, 'base')!496	offer_now(a, mut backend)!497	join(b, mut backend)!498	put(a.root, 'same.txt', 'A version\n')!499	make_save(a, 'A edits')!500	offer_now(a, mut backend)!501	put(b.root, 'same.txt', 'B version\n')!502	make_save(b, 'B edits')!503504	report := steal(b, mut backend, StealOptions{505		mine: true506	})!507	assert report.kept_mine == 1508	assert os.read_file(os.join_path(b.root, 'same.txt'))! == 'B version\n'509	// The final save says what it kept.510	assert head_of(b).message.contains('combine: kept mine for 1 file')511	// The pre-combine tree is still reachable in history.512	assert head_of(b).restores == ''513	assert history.all_saves(b)!.len >= 4514}515516fn test_flags_travel_with_the_saves() {517	base := scratch('flags')!518	defer {519		os.rmdir_all(base) or {}520	}521	mut backend := remote.new_folder(os.join_path(base, 'remote'))!522	mut a := open_repo(machine('flag_a')!)!523	defer {524		a.close()525	}526	mut b := open_repo(machine('flag_b')!)!527	defer {528		b.close()529	}530	put(a.root, 'a.txt', 'one\n')!531	save := make_save(a, 'suspect save')!532	events.flag(a, save.id, 'look at this')!533	offer_now(a, mut backend)!534535	// B has nothing yet, so a fetch brings the save and its flag across.536	fetched := fetch_back_to_known(b, mut backend, 'proj')!537	assert fetched.events_out.len == 1538	assert fetched.events_out[0].kind == events.kind_flag539	b.begin()!540	write_fetched(b, fetched)!541	history.set_head(b, fetched.head)!542	b.commit()!543	state := events.flag_state(b, save.id)!544	assert state.flagged545	assert state.reason == 'look at this'546}547548fn test_a_second_offer_racing_head_is_refused_not_forced() {549	base := scratch('race')!550	defer {551		os.rmdir_all(base) or {}552	}553	mut backend := remote.new_folder(os.join_path(base, 'remote'))!554	mut a := open_repo(machine('race_a')!)!555	defer {556		a.close()557	}558	put(a.root, 'a.txt', 'one\n')!559	make_save(a, 'base')!560	offer_now(a, mut backend)!561562	// Someone else replaces head behind our back.563	assert backend.put_if_match(head_key('proj'), 'a-save-we-do-not-have'.bytes(),564		backend.get(head_key('proj'))!.tag)!565566	put(a.root, 'a.txt', 'two\n')!567	make_save(a, 'second')!568	if _ := offer_now(a, mut backend) {569		assert false, 'offering while the remote head moved must be refused'570	} else {571		assert err.msg().contains('run koh steal')572	}573}574575// join makes a brand new machine share the remote's line.576fn join(store &storage.Store, mut backend remote.Backend) ! {577	fetched := fetch_repo(mut backend, 'proj')!578	store.begin()!579	write_fetched(store, fetched)!580	history.set_head(store, fetched.head)!581	store.commit()!582	snapshot.restore_files(store, store.root, snapshot.load(store.root), history.files_of(store,583		fetched.head)!, [])!584	store.set_state('remote_repo', 'proj')!585}586587struct FaultyBackend {588mut:589	inner      remote.Backend590	writes     int591	reads      int592	fail_write int // fail when the write counter reaches this, 0 never593	fail_read  int594	// fail every delete while set595	fail_delete bool596	// race_format stands in for another machine writing the format key first:597	// the first `format` write loses, to a value this koh does not speak.598	race_format bool599	raced       bool600}601602fn (mut f FaultyBackend) get(key string) !remote.Object {603	f.reads++604	if f.fail_read > 0 && f.reads >= f.fail_read {605		return error('injected read failure')606	}607	return f.inner.get(key)!608}609610fn (mut f FaultyBackend) list(prefix string) ![]string {611	return f.inner.list(prefix)!612}613614fn (mut f FaultyBackend) put_if_absent(key string, body []u8) !bool {615	f.writes++616	if f.fail_write > 0 && f.writes >= f.fail_write {617		return error('injected write failure')618	}619	if f.race_format && !f.raced && key.ends_with('/format') {620		f.raced = true621		f.inner.put_if_absent(key, 'koh-remote 2'.bytes())!622		return false623	}624	return f.inner.put_if_absent(key, body)!625}626627fn (mut f FaultyBackend) put_if_match(key string, body []u8, tag string) !bool {628	f.writes++629	if f.fail_write > 0 && f.writes >= f.fail_write {630		return error('injected write failure')631	}632	return f.inner.put_if_match(key, body, tag)!633}634635fn (mut f FaultyBackend) delete(key string) ! {636	if f.fail_delete {637		return error('injected delete failure')638	}639	f.inner.delete(key)!640}641642// Every save offers after it is made, so a one-file change must cost one643// object, not one conditional write per file in the repo: on S3 each of those644// is a round trip.645fn test_an_offer_sends_only_the_objects_a_save_adds() {646	base := scratch('offer_diff')!647	defer {648		os.rmdir_all(base) or {}649	}650	mut a := open_repo(machine('offer_diff_a')!)!651	defer {652		a.close()653	}654	for i in 0 .. 20 {655		put(a.root, 'f${i}.txt', 'file ${i}\n')!656	}657	make_save(a, 'twenty files')!658	mut backend := FaultyBackend{659		inner: remote.new_folder(os.join_path(base, 'remote'))!660	}661	offer(a, mut backend)!662	put(a.root, 'f3.txt', 'changed\n')!663	make_save(a, 'one change')!664	before := backend.writes665	report := offer(a, mut backend)!666	assert report.objects == 1667	// One object, one save record, one head swap.668	assert backend.writes - before == 3669}670671fn test_a_failed_offer_is_safe_to_re_run() {672	base := scratch('fault_offer')!673	defer {674		os.rmdir_all(base) or {}675	}676	remote_dir := os.join_path(base, 'remote')677	mut a := open_repo(machine('fault_a')!)!678	defer {679		a.close()680	}681	put(a.root, 'a.txt', 'one\n')!682	make_save(a, 'first')!683	put(a.root, 'a.txt', 'two\n')!684	make_save(a, 'second')!685686	// The first offer dies after the first write.687	mut flaky := FaultyBackend{688		inner:      remote.new_folder(remote_dir)!689		fail_write: 2690	}691	if _ := offer(a, mut flaky) {692		assert false, 'the injected failure should have surfaced'693	}694695	// Re-running with a healthy remote finishes the job: "already exists" is696	// success, so nothing is lost and nothing is duplicated.697	mut healthy := remote.new_folder(remote_dir)!698	report := offer(a, mut healthy)!699	assert report.saves == 2700	assert healthy.get(head_key('proj'))!.body.bytestr().trim_space() == head_of(a).id701	assert healthy.list('proj/saves')!.len == 2702}703704fn test_a_failed_steal_leaves_nothing_behind() {705	base := scratch('fault_steal')!706	defer {707		os.rmdir_all(base) or {}708	}709	remote_dir := os.join_path(base, 'remote')710	mut a := open_repo(machine('fault_s_a')!)!711	defer {712		a.close()713	}714	mut b := open_repo(machine('fault_s_b')!)!715	defer {716		b.close()717	}718	put(a.root, 'a.txt', 'from A\n')!719	make_save(a, 'A writes')!720	mut healthy := remote.new_folder(remote_dir)!721	offer(a, mut healthy)!722723	// B's fetch fails half way through reading the remote.724	mut flaky := FaultyBackend{725		inner:     remote.new_folder(remote_dir)!726		fail_read: 2727	}728	if _ := fetch_back_to_known(b, mut flaky, 'proj') {729		assert false, 'the injected read failure should have surfaced'730	}731	// Nothing was written: the store is untouched and still has no saves.732	assert history.head(b) == none733	assert b.object_count()! == 0734735	// A healthy retry works.736	fetched := fetch_back_to_known(b, mut healthy, 'proj')!737	b.begin()!738	write_fetched(b, fetched)!739	history.set_head(b, fetched.head)!740	b.commit()!741	snapshot.restore_files(b, b.root, snapshot.load(b.root), history.files_of(b, fetched.head)!, [])!742	assert os.read_file(os.join_path(b.root, 'a.txt'))! == 'from A\n'743}744745fn test_an_interrupted_strip_is_idempotent() {746	// The local half of a strip is one transaction, so an interrupted strip is747	// simply a strip that did not happen; re-running it must land the same748	// result once, not twice.749	base := scratch('fault_strip')!750	defer {751		os.rmdir_all(base) or {}752	}753	mut a := open_repo(machine('fault_strip_a')!)!754	defer {755		a.close()756	}757	put(a.root, 'secret.txt', 'shh\n')!758	put(a.root, 'keep.txt', 'fine\n')!759	save := make_save(a, 'add both')!760761	for _ in 0 .. 2 {762		strip_local(a, 'secret.txt', '')!763	}764	files := history.files_of(a, save.id)!765	// The repo's own `.kohignore` is tracked content, so it stays; only the766	// stripped path goes.767	assert files.map(it.path) == ['.kohignore', 'keep.txt']768	assert events.strip_events(a)!.len == 1769}770771// SQLite's LIKE ignores ASCII case, so a strip of `docs` must not reach into772// `Docs/`, and `a_b` must not reach `aXb`: strip destroys, so it matches exactly.773// The tree is built by hand: on macOS `Docs` and `docs` are one folder on disk,774// but a save made on Linux can hold both.775fn test_a_strip_matches_the_path_exactly() {776	mut a := open_repo(machine('strip_exact')!)!777	defer {778		a.close()779	}780	hash := a.put_object('x\n'.bytes())!781	mut files := []snapshot.FileEntry{}782	for path in ['DOCS.txt', 'Docs/keep.txt', 'a_b/x.txt', 'aXb/y.txt', 'docs/secret.txt'] {783		files << snapshot.FileEntry{784			path: path785			hash: hash786		}787	}788	save := history.save_tree(a, '', files, history.SaveInput{789		message: 'add all'790	})!791	assert strip_scope(a, 'docs', '')!.files == 1792	strip_local(a, 'docs', '')!793	strip_local(a, 'a_b', '')!794	assert history.files_of(a, save.id)!.map(it.path) == ['DOCS.txt', 'Docs/keep.txt', 'aXb/y.txt']795}796797fn test_a_strip_reaches_the_remote_and_other_machines() {798	base := scratch('strip_sync')!799	defer {800		os.rmdir_all(base) or {}801	}802	mut a := open_repo(machine('strip_a')!)!803	defer {804		a.close()805	}806	mut b := open_repo(machine('strip_b')!)!807	defer {808		b.close()809	}810	put(a.root, 'secrets.env', 'api_key=1\n')!811	put(a.root, 'keep.txt', 'fine\n')!812	save := make_save(a, 'add both')!813	mut backend := remote.new_folder(os.join_path(base, 'remote'))!814	offer_now(a, mut backend)!815	join(b, mut backend)!816	assert b.object_count()! > 0817818	// A strips the path locally, the way `koh strip` does, then tells the819	// remote.820	mut secret_hash := ''821	for file in history.files_of(a, save.id)! {822		if file.path == 'secrets.env' {823			secret_hash = file.hash824		}825	}826	assert secret_hash != ''827	strip_local(a, 'secrets.env', '')!828	report := push_strip(a, mut backend, 'secrets.env')!829	assert report.event_sent830	assert report.records == 1831832	// The remote's copy of the save no longer lists the file, and the object is833	// gone from the remote.834	record := decode_save(backend.get(save_key('proj', save.id))!.body)!835	for file in record.files {836		assert file.path != 'secrets.env'837	}838	// The stripped object is gone from the remote; the ones still referenced839	// are not.840	assert !backend.get(object_key('proj', secret_hash))!.found841	assert backend.list('proj/objects')!.len == 2842843	// Another machine hears about it on its next steal and applies it.844	b.begin()!845	fetched := fetch_back_to_known(b, mut backend, 'proj')!846	write_fetched(b, fetched)!847	b.commit()!848	mut paths := []string{}849	for file in history.files_of(b, save.id)! {850		paths << file.path851	}852	assert 'secrets.env' !in paths853	assert 'keep.txt' in paths854855	// The event arrives under its own ID, so it is applied once: B's offer adds856	// no second copy, and a file B saves again after the strip stays saved857	// through B's next steal.858	assert events.strip_events(b)!.map(it.id) == events.strip_events(a)!.map(it.id)859	put(b.root, 'secrets.env', 'rotated\n')!860	readded := make_save(b, 'add the rotated key back')!861	offer_now(b, mut backend)!862	assert backend.list('proj/events')!.len == 1863	b.begin()!864	write_fetched(b, fetch_back_to_known(b, mut backend, 'proj')!)!865	b.commit()!866	assert 'secrets.env' in history.files_of(b, readded.id)!.map(it.path)867}868869// A strip removes a path from the saves that existed when it was made. A key870// rotated and saved again afterwards is new work: a machine that clones the871// repo later must get it, not strip it on arrival.872fn test_a_clone_keeps_a_file_saved_again_after_a_strip() {873	base := scratch('strip_clone')!874	defer {875		os.rmdir_all(base) or {}876	}877	mut backend := remote.new_folder(os.join_path(base, 'remote'))!878	mut a := open_repo(machine('strip_clone_a')!)!879	defer {880		a.close()881	}882	put(a.root, 'secrets.env', 'api_key=1\n')!883	old := make_save(a, 'leak the key')!884	offer_now(a, mut backend)!885	strip_local(a, 'secrets.env', '')!886	push_strip(a, mut backend, 'secrets.env')!887	// Saves after the strip must be later in time, as they would be for real.888	put(a.root, 'secrets.env', 'api_key=2\n')!889	rotated := history.save_tree(a, a.root, snapshot.walk(a, a.root, snapshot.load(a.root))!, history.SaveInput{890		message:    'rotate the key'891		created_at: events.strip_events(a)!.last().created_at + 60892	})!893	offer_now(a, mut backend)!894895	mut c := open_repo(machine('strip_clone_c')!)!896	defer {897		c.close()898	}899	join(c, mut backend)!900	assert 'secrets.env' in history.files_of(c, rotated.id)!.map(it.path)901	assert 'secrets.env' !in history.files_of(c, old.id)!.map(it.path)902	assert os.read_file(os.join_path(c.root, 'secrets.env'))! == 'api_key=2\n'903}904905// The local half commits before the remote hears anything, so a remote failure906// leaves nothing to find locally; the pending note is what lets a re-run907// finish. Objects a remote-only save still needs must survive the strip.908fn test_an_interrupted_remote_strip_finishes_when_re_run() {909	base := scratch('strip_resume')!910	defer {911		os.rmdir_all(base) or {}912	}913	remote_dir := os.join_path(base, 'remote')914	mut backend := remote.new_folder(remote_dir)!915	mut a := open_repo(machine('resume_a')!)!916	defer {917		a.close()918	}919	mut b := open_repo(machine('resume_b')!)!920	defer {921		b.close()922	}923	put(a.root, 'secrets.env', 'api_key=1\n')!924	put(a.root, 'shared.env', 'same bytes on B\n')!925	save := make_save(a, 'add secrets')!926	offer_now(a, mut backend)!927	join(b, mut backend)!928	put(b.root, 'copy.txt', 'same bytes on B\n')!929	b_save := make_save(b, 'B keeps a copy')!930	offer_now(b, mut backend)!931	shared_hash := storage.hash_hex('same bytes on B\n'.bytes())932	secret_hash := storage.hash_hex('api_key=1\n'.bytes())933934	strip_local(a, 'secrets.env', '')!935	// Write 1 uploads the event and write 2 rewrites the first record; B's save,936	// made from A's tree, lists the file too, and its rewrite (write 3) fails.937	mut flaky := FaultyBackend{938		inner:      remote.new_folder(remote_dir)!939		fail_write: 3940	}941	if _ := push_strip(a, mut flaky, 'secrets.env') {942		assert false, 'the injected failure should have surfaced'943	}944	assert strip_pending(a, 'secrets.env')945	assert strip_local(a, 'secrets.env', '')!.files_removed == 0946	report := push_strip(a, mut backend, 'secrets.env')!947	assert report.records == 1948	assert !strip_pending(a, 'secrets.env')949	assert !backend.get(object_key('proj', secret_hash))!.found950	record := decode_save(backend.get(save_key('proj', save.id))!.body)!951	assert 'secrets.env' !in record.files.map(it.path)952	b_record := decode_save(backend.get(save_key('proj', b_save.id))!.body)!953	assert 'secrets.env' !in b_record.files.map(it.path)954955	// B's save still names the shared bytes, so stripping A's copy keeps them.956	strip_local(a, 'shared.env', '')!957	push_strip(a, mut backend, 'shared.env')!958	assert backend.get(object_key('proj', shared_hash))!.found959}960961// A machine that has not heard of a strip must not offer: its records still962// list the stripped path, and nothing would rewrite them on the remote again.963fn test_offer_waits_for_an_unapplied_strip() {964	base := scratch('strip_first')!965	defer {966		os.rmdir_all(base) or {}967	}968	mut backend := remote.new_folder(os.join_path(base, 'remote'))!969	mut a := open_repo(machine('strip_first_a')!)!970	defer {971		a.close()972	}973	mut b := open_repo(machine('strip_first_b')!)!974	defer {975		b.close()976	}977	put(a.root, 'secrets.env', 'api_key=1\n')!978	make_save(a, 'add secrets')!979	offer_now(a, mut backend)!980	join(b, mut backend)!981	strip_local(a, 'secrets.env', '')!982	push_strip(a, mut backend, 'secrets.env')!983	put(b.root, 'more.txt', 'B keeps working\n')!984	later := make_save(b, 'B saves with the secret still in its tree')!985	if _ := offer_now(b, mut backend) {986		assert false, 'B offered records that still list the stripped path'987	}988	steal_now(b, mut backend)!989	offer_now(b, mut backend)!990	record := decode_save(backend.get(save_key('proj', later.id))!.body)!991	assert 'secrets.env' !in record.files.map(it.path)992}993994// A strip whose object deletions failed, followed by a second strip of the same995// path, must still delete the first strip's objects when it finishes.996fn test_a_second_strip_keeps_the_first_ones_unfinished_objects() {997	base := scratch('strip_twice')!998	defer {999		os.rmdir_all(base) or {}1000	}1001	remote_dir := os.join_path(base, 'remote')1002	mut backend := remote.new_folder(remote_dir)!1003	mut a := open_repo(machine('strip_twice_a')!)!1004	defer {1005		a.close()1006	}1007	put(a.root, 'secrets.env', 'first key\n')!1008	make_save(a, 'first key')!1009	offer_now(a, mut backend)!1010	strip_local(a, 'secrets.env', '')!1011	mut flaky := FaultyBackend{1012		inner:       remote.new_folder(remote_dir)!1013		fail_delete: true1014	}1015	if _ := push_strip(a, mut flaky, 'secrets.env') {1016		assert false, 'the injected delete failure should have surfaced'1017	}1018	put(a.root, 'secrets.env', 'second key\n')!1019	make_save(a, 'second key')!1020	offer_now(a, mut backend)!1021	strip_local(a, 'secrets.env', '')!1022	push_strip(a, mut backend, 'secrets.env')!1023	for key in ['first key\n', 'second key\n'] {1024		assert !backend.get(object_key('proj', storage.hash_hex(key.bytes())))!.found1025	}1026}10271028// Unfinished strips of one path in different scopes finish together.1029fn test_unfinished_strips_of_one_path_in_different_saves_finish_together() {1030	base := scratch('strip_scopes')!1031	defer {1032		os.rmdir_all(base) or {}1033	}1034	remote_dir := os.join_path(base, 'remote')1035	mut backend := remote.new_folder(remote_dir)!1036	mut a := open_repo(machine('strip_scopes_a')!)!1037	defer {1038		a.close()1039	}1040	put(a.root, 'secrets.env', 'first key\n')!1041	first := make_save(a, 'first key')!1042	put(a.root, 'secrets.env', 'second key\n')!1043	second := make_save(a, 'second key')!1044	offer_now(a, mut backend)!1045	strip_local(a, 'secrets.env', first.id)!1046	// Write 1 uploads the event; write 2, the record rewrite, fails.1047	mut flaky := FaultyBackend{1048		inner:      remote.new_folder(remote_dir)!1049		fail_write: 21050	}1051	if _ := push_strip(a, mut flaky, 'secrets.env') {1052		assert false, 'the injected failure should have surfaced'1053	}1054	strip_local(a, 'secrets.env', second.id)!1055	push_strip(a, mut backend, 'secrets.env')!1056	assert !strip_pending(a, 'secrets.env')1057	for save in [first, second] {1058		record := decode_save(backend.get(save_key('proj', save.id))!.body)!1059		assert 'secrets.env' !in record.files.map(it.path)1060	}1061	for key in ['first key\n', 'second key\n'] {1062		assert !backend.get(object_key('proj', storage.hash_hex(key.bytes())))!.found1063	}1064}10651066// Stripping a path, re-adding it, and stripping it again is two strips; a1067// machine that heard about the first must still apply the second.1068fn test_a_second_strip_of_the_same_path_reaches_other_machines() {1069	base := scratch('strip_again')!1070	defer {1071		os.rmdir_all(base) or {}1072	}1073	mut backend := remote.new_folder(os.join_path(base, 'remote'))!1074	mut a := open_repo(machine('strip_again_a')!)!1075	defer {1076		a.close()1077	}1078	mut b := open_repo(machine('strip_again_b')!)!1079	defer {1080		b.close()1081	}1082	put(a.root, 'secrets.env', 'first key\n')!1083	make_save(a, 'first key')!1084	offer_now(a, mut backend)!1085	join(b, mut backend)!1086	strip_local(a, 'secrets.env', '')!1087	push_strip(a, mut backend, 'secrets.env')!1088	steal_now(b, mut backend)!1089	// Strip leaves the file on disk; deleting it is the user's part.1090	os.rm(os.join_path(b.root, 'secrets.env'))!1091	put(a.root, 'secrets.env', 'second key\n')!1092	second := make_save(a, 'second key')!1093	offer_now(a, mut backend)!1094	steal_now(b, mut backend)!1095	assert 'secrets.env' in history.files_of(b, second.id)!.map(it.path)1096	strip_local(a, 'secrets.env', '')!1097	push_strip(a, mut backend, 'secrets.env')!1098	steal_now(b, mut backend)!1099	assert 'secrets.env' !in history.files_of(b, second.id)!.map(it.path)1100}11011102// A clash on a path the other machine stripped is no clash: the strip removes1103// the path from every save, so there is nothing to choose.1104fn test_a_stripped_path_is_not_asked_about() {1105	base := scratch('clash_strip')!1106	defer {1107		os.rmdir_all(base) or {}1108	}1109	mut backend := remote.new_folder(os.join_path(base, 'remote'))!1110	mut a := open_repo(machine('clash_strip_a')!)!1111	defer {1112		a.close()1113	}1114	mut b := open_repo(machine('clash_strip_b')!)!1115	defer {1116		b.close()1117	}1118	put(a.root, 'secrets.env', 'key one\n')!1119	make_save(a, 'base')!1120	offer_now(a, mut backend)!1121	join(b, mut backend)!1122	put(a.root, 'secrets.env', 'key two\n')!1123	make_save(a, 'A rotates')!1124	offer_now(a, mut backend)!1125	strip_local(a, 'secrets.env', '')!1126	push_strip(a, mut backend, 'secrets.env')!1127	put(b.root, 'secrets.env', 'key three\n')!1128	mine := make_save(b, 'B rotates')!1129	report := steal(b, mut backend, StealOptions{})!1130	assert report.clashes.len == 01131	for save in history.all_saves(b)! {1132		assert 'secrets.env' !in history.files_of(b, save.id)!.map(it.path)1133	}1134	assert history.by_id(b, mine.id) != none1135}11361137// A strip scoped to the shared base save changes what the replay sees; the1138// clashes must be found on the same trees, or the replay meets a conflict.1139fn test_a_strip_of_the_shared_base_is_seen_before_asking() {1140	base := scratch('clash_base_strip')!1141	defer {1142		os.rmdir_all(base) or {}1143	}1144	mut backend := remote.new_folder(os.join_path(base, 'remote'))!1145	mut a := open_repo(machine('base_strip_a')!)!1146	defer {1147		a.close()1148	}1149	mut b := open_repo(machine('base_strip_b')!)!1150	defer {1151		b.close()1152	}1153	put(a.root, 'notes.txt', 'shared\n')!1154	common := make_save(a, 'base')!1155	offer_now(a, mut backend)!1156	join(b, mut backend)!1157	put(a.root, 'other.txt', 'A moves on\n')!1158	make_save(a, 'A moves on')!1159	offer_now(a, mut backend)!1160	strip_local(a, 'notes.txt', common.id)!1161	push_strip(a, mut backend, 'notes.txt')!1162	put(b.root, 'notes.txt', 'B edits\n')!1163	make_save(b, 'B edits notes')!1164	if _ := steal(b, mut backend, StealOptions{}) {1165		assert false, 'with the base stripped, notes.txt differs on both sides'1166	} else {1167		assert err.msg().contains('notes.txt changed on both machines')1168	}1169	report := steal(b, mut backend, StealOptions{1170		mine: true1171	})!1172	assert report.clashes == ['notes.txt']1173	assert os.read_file(os.join_path(b.root, 'notes.txt'))! == 'B edits\n'1174}11751176// A folder with files but no saves has nothing to combine with; a steal that1177// fast-forwarded into it would overwrite whatever shares a name.1178fn test_steal_into_a_folder_with_unsaved_files_refuses() {1179	base := scratch('steal_unsaved')!1180	defer {1181		os.rmdir_all(base) or {}1182	}1183	mut backend := remote.new_folder(os.join_path(base, 'remote'))!1184	mut a := open_repo(machine('unsaved_a')!)!1185	defer {1186		a.close()1187	}1188	put(a.root, 'notes.txt', 'from A\n')!1189	make_save(a, 'A writes')!1190	offer_now(a, mut backend)!1191	b_root := machine('unsaved_b')!1192	mut b := storage.create(b_root)!1193	defer {1194		b.close()1195	}1196	put(b_root, 'notes.txt', 'never saved\n')!1197	// Only a repo that already knows its remote name gets this far.1198	b.set_state('remote_repo', 'proj')!1199	if _ := steal(b, mut backend, StealOptions{}) {1200		assert false, 'steal overwrote a folder with unsaved files'1201	} else {1202		assert err.msg() == no_saves_here1203	}1204	assert os.read_file(os.join_path(b_root, 'notes.txt'))! == 'never saved\n'1205	// A fresh `koh init` folder, holding only the default ignore list, is fine.1206	os.rm(os.join_path(b_root, 'notes.txt'))!1207	put(b_root, snapshot.ignore_file, snapshot.default_ignore)!1208	steal(b, mut backend, StealOptions{})!1209	assert os.read_file(os.join_path(b_root, 'notes.txt'))! == 'from A\n'1210}12111212// The document asks steal to warn about every incoming flagged save, so the1213// report names them.1214fn test_steal_reports_incoming_flagged_saves() {1215	base := scratch('flag_warn')!1216	defer {1217		os.rmdir_all(base) or {}1218	}1219	mut backend := remote.new_folder(os.join_path(base, 'remote'))!1220	mut a := open_repo(machine('flag_warn_a')!)!1221	defer {1222		a.close()1223	}1224	mut b := open_repo(machine('flag_warn_b')!)!1225	defer {1226		b.close()1227	}1228	put(a.root, 'a.txt', 'one\n')!1229	make_save(a, 'fine')!1230	offer_now(a, mut backend)!1231	join(b, mut backend)!1232	put(a.root, 'a.txt', 'two\n')!1233	suspect := make_save(a, 'suspect')!1234	put(a.root, 'a.txt', 'three\n')!1235	make_save(a, 'also fine')!1236	events.flag(a, suspect.id, 'broke the build')!1237	offer_now(a, mut backend)!1238	report := steal_now(b, mut backend)!1239	assert report.flagged.map(it.save_id) == [suspect.id]1240	assert report.flagged[0].reason == 'broke the build'1241}12421243// head_of unwraps the head for tests that know the repo has saves.1244fn head_of(store &storage.Store) history.Save {1245	return history.head(store) or { panic('this repo has no head') }1246}12471248// A remote says what it is, so two koh versions never half-understand one1249// bucket. The first offer of a repo records the layout.1250fn test_the_first_offer_records_the_remote_format() {1251	base := scratch('format_write')!1252	defer {1253		os.rmdir_all(base) or {}1254	}1255	mut backend := remote.new_folder(os.join_path(base, 'remote'))!1256	mut a := open_repo(machine('format_write_a')!)!1257	defer {1258		a.close()1259	}1260	put(a.root, 'a.txt', 'one\n')!1261	make_save(a, 'first')!1262	offer_now(a, mut backend)!1263	assert backend.get(format_key('proj'))!.body.bytestr().trim_space() == format_value1264}12651266// A repo offered before the key existed is version 1: it still syncs, and the1267// next offer records the key then.1268fn test_a_remote_without_a_format_still_syncs() {1269	base := scratch('format_old')!1270	defer {1271		os.rmdir_all(base) or {}1272	}1273	mut backend := remote.new_folder(os.join_path(base, 'remote'))!1274	mut a := open_repo(machine('format_old_a')!)!1275	defer {1276		a.close()1277	}1278	put(a.root, 'a.txt', 'one\n')!1279	make_save(a, 'first')!1280	offer_now(a, mut backend)!1281	// Stand in for a bucket offered before the key existed.1282	backend.delete(format_key('proj'))!1283	mut b := open_repo(machine('format_old_b')!)!1284	defer {1285		b.close()1286	}1287	join(b, mut backend)!1288	assert head_of(b).id == head_of(a).id1289	put(a.root, 'a.txt', 'two\n')!1290	make_save(a, 'second')!1291	offer_now(a, mut backend)!1292	assert backend.get(format_key('proj'))!.body.bytestr().trim_space() == format_value1293	report := steal_now(b, mut backend)!1294	assert report.head == head_of(a).id1295}12961297// A remote that speaks another layout is refused loudly, on offer and on1298// steal, rather than half-read.1299fn test_an_unknown_remote_format_is_refused() {1300	base := scratch('format_unknown')!1301	defer {1302		os.rmdir_all(base) or {}1303	}1304	mut backend := remote.new_folder(os.join_path(base, 'remote'))!1305	mut a := open_repo(machine('format_bad_a')!)!1306	defer {1307		a.close()1308	}1309	put(a.root, 'a.txt', 'one\n')!1310	make_save(a, 'first')!1311	offer_now(a, mut backend)!1312	backend.delete(format_key('proj'))!1313	backend.put_if_absent(format_key('proj'), 'koh-remote 2'.bytes())!1314	if _ := offer_now(a, mut backend) {1315		assert false, 'offer must refuse a format it does not speak'1316	} else {1317		assert err.msg().contains('koh-remote 2')1318	}1319	if _ := steal_now(a, mut backend) {1320		assert false, 'steal must refuse a format it does not speak'1321	} else {1322		assert err.msg().contains('koh-remote 2')1323	}1324	if _ := fetch_repo(mut backend, 'proj') {1325		assert false, 'a clone must refuse a format it does not speak'1326	} else {1327		assert err.msg().contains('koh-remote 2')1328	}1329}13301331// Two machines offering a new repo at once both find no format key; the loser1332// of the conditional write must read back the winner's value and refuse it,1333// not carry on against a remote it cannot read.1334fn test_a_lost_format_write_is_read_back_and_refused() {1335	base := scratch('format_race')!1336	defer {1337		os.rmdir_all(base) or {}1338	}1339	mut inner := remote.new_folder(os.join_path(base, 'remote'))!1340	mut a := open_repo(machine('format_race_a')!)!1341	defer {1342		a.close()1343	}1344	put(a.root, 'a.txt', 'one\n')!1345	make_save(a, 'first')!1346	mut backend := remote.Backend(FaultyBackend{1347		inner:       inner1348		race_format: true1349	})1350	if _ := offer_now(a, mut backend) {1351		assert false, 'offer must refuse the format another machine wrote first'1352	} else {1353		assert err.msg().contains('koh-remote 2')1354	}1355}