* [PATCH 0/1] [v2.23.0 BUG] commit-graph: fix bug around octopus merges @ 2019-08-05 16:43 Derrick Stolee via GitGitGadget 2019-08-05 16:43 ` [PATCH 1/1] " Derrick Stolee via GitGitGadget 0 siblings, 1 reply; 5+ messages in thread From: Derrick Stolee via GitGitGadget @ 2019-08-05 16:43 UTC (permalink / raw) To: git; +Cc: peff, avarab, jrnieder, steadmon, Junio C Hamano I come, hat in hand, with a bug-fix for a bug that I wrote. I just happened to discover this issue while playing around with turning the commit-graph on by default and stumbled into this warning. Please see the commit message for full details, but putting octopus merges in a tip commit-graph file in the incremental format [1] would cause the file to not load because Git thinks the base commit-graphs do not have the right hashes. It is very likely that a more careful patch would allow this warning to become an error during git commit-graph verify, but I wanted to minimize the change for this quick bug fix. Thanks, -Stolee [1] https://public-inbox.org/git/pull.184.v6.git.gitgitgadget@gmail.com/ Derrick Stolee (1): commit-graph: fix bug around octopus merges commit-graph.c | 2 +- t/t5324-split-commit-graph.sh | 4 +++- 2 files changed, 4 insertions(+), 2 deletions(-) base-commit: 5b15eb397d176c557a82e872d6b4043aa7589874 Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-308%2Fderrickstolee%2Fcommit-graph-octopus-bug-v1 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-308/derrickstolee/commit-graph-octopus-bug-v1 Pull-Request: https://github.com/gitgitgadget/git/pull/308 -- gitgitgadget ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH 1/1] commit-graph: fix bug around octopus merges 2019-08-05 16:43 [PATCH 0/1] [v2.23.0 BUG] commit-graph: fix bug around octopus merges Derrick Stolee via GitGitGadget @ 2019-08-05 16:43 ` Derrick Stolee via GitGitGadget 2019-08-06 9:21 ` SZEDER Gábor 0 siblings, 1 reply; 5+ messages in thread From: Derrick Stolee via GitGitGadget @ 2019-08-05 16:43 UTC (permalink / raw) To: git; +Cc: peff, avarab, jrnieder, steadmon, Junio C Hamano, Derrick Stolee From: Derrick Stolee <dstolee@microsoft.com> In 1771be90 "commit-graph: merge commit-graph chains" (2019-06-18), the method sort_and_scan_merged_commits() was added to merge the commit lists of two commit-graph files in the incremental format. Unfortunately, there was an off-by-one error in that method around incrementing num_extra_edges, which leads to an incorrect offset for the base graph chunk. When we store an octopus merge in the commit-graph file, we store the first parent in the normal place, but use the second parent position to point into the "extra edges" chunk where the remaining parents exist. This means we should be adding "num_parents - 1" edges to this list, not "num_parents - 2". That is the basic error. The reason this was not caught in the test suite is more subtle. In 5324-split-commit-graph.sh, we test creating an octopus merge and adding it to the tip of a commit-graph chain, then verify the result. This _should_ have caught the problem, except that when we load the commit-graph files we were overly careful to not fail when the commit-graph chain does not match. This care was on purpose to avoid race conditions as one process reads the chain and another process modifies it. In such a case, the reading process outputs the following message to stderr: warning: commit-graph chain does not match These warnings are output in the test suite, but ignored. By checking the stderr of `git commit-graph verify` to include the expected progress output, it will now catch this error. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> --- commit-graph.c | 2 +- t/t5324-split-commit-graph.sh | 4 +++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/commit-graph.c b/commit-graph.c index c91e6f0fb8..1aaf02879b 100644 --- a/commit-graph.c +++ b/commit-graph.c @@ -1629,7 +1629,7 @@ static void sort_and_scan_merged_commits(struct write_commit_graph_context *ctx) num_parents++; if (num_parents > 2) - ctx->num_extra_edges += num_parents - 2; + ctx->num_extra_edges += num_parents - 1; } } diff --git a/t/t5324-split-commit-graph.sh b/t/t5324-split-commit-graph.sh index 03f45a1ed9..99f4ef4c19 100755 --- a/t/t5324-split-commit-graph.sh +++ b/t/t5324-split-commit-graph.sh @@ -319,7 +319,9 @@ test_expect_success 'add octopus merge' ' git merge commits/3 commits/4 && git branch merge/octopus && git commit-graph write --reachable --split && - git commit-graph verify && + git commit-graph verify 2>err && + test_line_count = 3 err && + test_i18ngrep ! warning err && test_line_count = 3 $graphdir/commit-graph-chain ' -- gitgitgadget ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH 1/1] commit-graph: fix bug around octopus merges 2019-08-05 16:43 ` [PATCH 1/1] " Derrick Stolee via GitGitGadget @ 2019-08-06 9:21 ` SZEDER Gábor 2019-08-06 12:03 ` Derrick Stolee 0 siblings, 1 reply; 5+ messages in thread From: SZEDER Gábor @ 2019-08-06 9:21 UTC (permalink / raw) To: Derrick Stolee via GitGitGadget Cc: git, peff, avarab, jrnieder, steadmon, Junio C Hamano, Derrick Stolee On Mon, Aug 05, 2019 at 09:43:41AM -0700, Derrick Stolee via GitGitGadget wrote: > In such a case, the reading > process outputs the following message to stderr: > > warning: commit-graph chain does not match > > These warnings are output in the test suite, but ignored. By > checking the stderr of `git commit-graph verify` to include > the expected progress output, it will now catch this error. There should be a better way to check this than relying on the number of progress lines, e.g. 'git commit-graph verify' could print something specific, like "Verified 3 commit-graph files, all OK", to its standard output, and the test should check only that. Or check only that there is no warning on standard error. On one hand, see the recent commits 077b979891 (t3404: make the 'rebase.missingCommitsCheck=ignore' test more focused, 2019-06-24) and bb431c3dad (t3420: remove progress lines before comparing output, 2019-07-04), where we started to exclude the progress output from verification in tests like this that are not specifically about progress output. On the other hand, one of my fun side-projects is to run some semi-automated and souped-up CI builds of currently cooking topics, which include a custom GETTEXT_POISON mode [1], where the poisoned translated progress output in this new test looks like this [2]: V.e.r.i.f.y.i.n.g. .c.o.m.m.i.t.s. .i.n. .c.o.m.m.i.t. .g.r.a.p.h.: 100% (1/1), d.o.n.e.. V.e.r.i.f.y.i.n.g. .c.o.m.m.i.t.s. .i.n. .c.o.m.m.i.t. .g.r.a.p.h.: 100% (5/5), d.o.n.e.. V.e.r.i.f.y.i.n.g. .c.o.m.m.i.t.s. .i.n. .c.o.m.m.i.t. .g.r.a.p.h.: 100% (12/12), d.o.n.e.. So this makes the progress lines almost twice as long, and as the last commit-graph file contains double-digit commits, the length of the progress line just happens to exceed the width of a 80 character terminal, and gets line wrapped. This throws off the line count check, as there are now 4 lines on standard error instead of the expected 3. [1] https://public-inbox.org/git/20181022202241.18629-1-szeder.dev@gmail.com/ [2] https://travis-ci.org/szeder/git-cooking-topics-for-travis-ci/jobs/568120252#L4120 Note that the highlighted line is in the 'after failure' fold, and your browser might unhelpfully fold it up before you could take a good look. > diff --git a/t/t5324-split-commit-graph.sh b/t/t5324-split-commit-graph.sh > index 03f45a1ed9..99f4ef4c19 100755 > --- a/t/t5324-split-commit-graph.sh > +++ b/t/t5324-split-commit-graph.sh > @@ -319,7 +319,9 @@ test_expect_success 'add octopus merge' ' > git merge commits/3 commits/4 && > git branch merge/octopus && > git commit-graph write --reachable --split && > - git commit-graph verify && > + git commit-graph verify 2>err && > + test_line_count = 3 err && > + test_i18ngrep ! warning err && > test_line_count = 3 $graphdir/commit-graph-chain > ' > > -- > gitgitgadget ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 1/1] commit-graph: fix bug around octopus merges 2019-08-06 9:21 ` SZEDER Gábor @ 2019-08-06 12:03 ` Derrick Stolee 2019-08-06 15:19 ` SZEDER Gábor 0 siblings, 1 reply; 5+ messages in thread From: Derrick Stolee @ 2019-08-06 12:03 UTC (permalink / raw) To: SZEDER Gábor, Derrick Stolee via GitGitGadget Cc: git, peff, avarab, jrnieder, steadmon, Junio C Hamano, Derrick Stolee On 8/6/2019 5:21 AM, SZEDER Gábor wrote: > On Mon, Aug 05, 2019 at 09:43:41AM -0700, Derrick Stolee via GitGitGadget wrote: > >> In such a case, the reading >> process outputs the following message to stderr: >> >> warning: commit-graph chain does not match >> >> These warnings are output in the test suite, but ignored. By >> checking the stderr of `git commit-graph verify` to include >> the expected progress output, it will now catch this error. > > There should be a better way to check this than relying on the number > of progress lines, e.g. 'git commit-graph verify' could print > something specific, like "Verified 3 commit-graph files, all OK", to > its standard output, and the test should check only that. Or check > only that there is no warning on standard error. > > On one hand, see the recent commits 077b979891 (t3404: make the > 'rebase.missingCommitsCheck=ignore' test more focused, 2019-06-24) and > bb431c3dad (t3420: remove progress lines before comparing output, > 2019-07-04), where we started to exclude the progress output from > verification in tests like this that are not specifically about > progress output. > > On the other hand, one of my fun side-projects is to run some > semi-automated and souped-up CI builds of currently cooking topics, > which include a custom GETTEXT_POISON mode [1], where the poisoned > translated progress output in this new test looks like this [2]: > > V.e.r.i.f.y.i.n.g. .c.o.m.m.i.t.s. .i.n. .c.o.m.m.i.t. .g.r.a.p.h.: 100% (1/1), d.o.n.e.. > V.e.r.i.f.y.i.n.g. .c.o.m.m.i.t.s. .i.n. .c.o.m.m.i.t. .g.r.a.p.h.: 100% (5/5), d.o.n.e.. > V.e.r.i.f.y.i.n.g. .c.o.m.m.i.t.s. .i.n. .c.o.m.m.i.t. .g.r.a.p.h.: > 100% (12/12), d.o.n.e.. > > So this makes the progress lines almost twice as long, and as the last > commit-graph file contains double-digit commits, the length of the > progress line just happens to exceed the width of a 80 character > terminal, and gets line wrapped. This throws off the line count > check, as there are now 4 lines on standard error instead of the > expected 3. Thanks for pointing out that the poison runs can change the number of lines. My intention was to ensure "we got the amount of output we expected" but it is enough to only use test_i18ngrep to check that no warnings occurred. Thanks, -Stolee ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 1/1] commit-graph: fix bug around octopus merges 2019-08-06 12:03 ` Derrick Stolee @ 2019-08-06 15:19 ` SZEDER Gábor 0 siblings, 0 replies; 5+ messages in thread From: SZEDER Gábor @ 2019-08-06 15:19 UTC (permalink / raw) To: Derrick Stolee Cc: Derrick Stolee via GitGitGadget, git, peff, avarab, jrnieder, steadmon, Junio C Hamano, Derrick Stolee On Tue, Aug 06, 2019 at 08:03:07AM -0400, Derrick Stolee wrote: > > On the other hand, one of my fun side-projects is to run some > > semi-automated and souped-up CI builds of currently cooking topics, > > which include a custom GETTEXT_POISON mode [1], where the poisoned > > translated progress output in this new test looks like this [2]: > > > > V.e.r.i.f.y.i.n.g. .c.o.m.m.i.t.s. .i.n. .c.o.m.m.i.t. .g.r.a.p.h.: 100% (1/1), d.o.n.e.. > > V.e.r.i.f.y.i.n.g. .c.o.m.m.i.t.s. .i.n. .c.o.m.m.i.t. .g.r.a.p.h.: 100% (5/5), d.o.n.e.. > > V.e.r.i.f.y.i.n.g. .c.o.m.m.i.t.s. .i.n. .c.o.m.m.i.t. .g.r.a.p.h.: > > 100% (12/12), d.o.n.e.. > > > > So this makes the progress lines almost twice as long, and as the last > > commit-graph file contains double-digit commits, the length of the > > progress line just happens to exceed the width of a 80 character > > terminal, and gets line wrapped. This throws off the line count > > check, as there are now 4 lines on standard error instead of the > > expected 3. > > Thanks for pointing out that the poison runs can change the number of lines. Hm, I'm afraid I was not clear enough, so let me clarify. A "regular" GIT_TEST_GETTEXT_POISON=1 test run does not change the number of lines. After it replaces the translated string with the '# GETTEXT POISON #' magic, the progress output will look like this: # GETTEXT POISON #: 41% (5/12) This will never grow long enough to trigger a line break. It's just one of my fun experiments [1] that makes translated strings twice as long, and thus triggers that line break. [1] https://github.com/szeder/git gettext-poison-scrambled-msg ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2019-08-06 15:19 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2019-08-05 16:43 [PATCH 0/1] [v2.23.0 BUG] commit-graph: fix bug around octopus merges Derrick Stolee via GitGitGadget 2019-08-05 16:43 ` [PATCH 1/1] " Derrick Stolee via GitGitGadget 2019-08-06 9:21 ` SZEDER Gábor 2019-08-06 12:03 ` Derrick Stolee 2019-08-06 15:19 ` SZEDER Gábor
Code repositories for project(s) associated with this public inbox https://80x24.org/mirrors/git.git This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).