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34 commits

Author SHA1 Message Date
Junio C Hamano f2e2136ad7 Merge branch 'md/test-cleanup'
Various test scripts have been updated for style and also correct
handling of exit status of various commands.

* md/test-cleanup:
  tests: order arguments to git-rev-list properly
  t9109: don't swallow Git errors upstream of pipes
  tests: don't swallow Git errors upstream of pipes
  t/*: fix ordering of expected/observed arguments
  tests: standardize pipe placement
  Documentation: add shell guidelines
  t/README: reformat Do, Don't, Keep in mind lists
2018-10-16 16:16:01 +09:00
Junio C Hamano 6d8f8ebb74 Merge branch 'ds/commit-graph-with-grafts'
The recently introduced commit-graph auxiliary data is incompatible
with mechanisms such as replace & grafts that "breaks" immutable
nature of the object reference relationship.  Disable optimizations
based on its use (and updating existing commit-graph) when these
incompatible features are in use in the repository.

* ds/commit-graph-with-grafts:
  commit-graph: close_commit_graph before shallow walk
  commit-graph: not compatible with uninitialized repo
  commit-graph: not compatible with grafts
  commit-graph: not compatible with replace objects
  test-repository: properly init repo
  commit-graph: update design document
  refs.c: upgrade for_each_replace_ref to be a each_repo_ref_fn callback
  refs.c: migrate internal ref iteration to pass thru repository argument
2018-10-16 16:15:59 +09:00
Matthew DeVore dcbaa0b361 t/*: fix ordering of expected/observed arguments
Fix various places where the ordering was obviously wrong, meaning it
was easy to find with grep.

Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-07 08:51:18 +09:00
Derrick Stolee ae0c89d41b t5318: use test_oid for HASH_LEN
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-09-17 08:10:32 -07:00
Ævar Arnfjörð Bjarmason 4a3ed63802 tests: fix and add lint for non-portable grep --file
The --file option to grep isn't in POSIX[1], but -f is[1]. Let's check
for that in the future, and fix the portability regression in
f237c8b6fe ("commit-graph: implement git-commit-graph write",
2018-04-02) that broke e.g. AIX.

1. http://pubs.opengroup.org/onlinepubs/009695399/utilities/grep.html

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-27 14:07:32 -07:00
Derrick Stolee 20fd6d5799 commit-graph: not compatible with grafts
Augment commit_graph_compatible(r) to return false when the given
repository r has commit grafts or is a shallow clone. Test that in these
situations we ignore existing commit-graph files and we do not write new
commit-graph files.

Helped-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-21 10:22:51 -07:00
Derrick Stolee d6538246d3 commit-graph: not compatible with replace objects
Create new method commit_graph_compatible(r) to check if a given
repository r is compatible with the commit-graph feature. Fill the
method with a check to see if replace-objects exist. Test this
interaction succeeds, including ignoring an existing commit-graph and
failing to write a new commit-graph. However, we do ensure that
we write a new commit-graph by setting read_replace_refs to 0, thereby
ignoring the replace refs.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-21 10:22:51 -07:00
Junio C Hamano 3bc484af74 Merge branch 'jt/commit-graph-per-object-store'
Test update.

* jt/commit-graph-per-object-store:
  t5318: avoid unnecessary command substitutions
2018-08-20 11:33:51 -07:00
Junio C Hamano 5dd54744b8 Merge branch 'ds/commit-graph-fsck'
Test fix.

* ds/commit-graph-fsck:
  t5318: use 'test_cmp_bin' to compare commit-graph files
2018-08-20 11:33:51 -07:00
SZEDER Gábor 3c4586301d t5318: avoid unnecessary command substitutions
Two tests added in dade47c06c (commit-graph: add repo arg to graph
readers, 2018-07-11) prepare the contents of 'expect' files by
'echo'ing the results of command substitutions.  That's unncessary,
avoid them by directly saving the output of the commands executed in
those command substitutions.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-13 12:09:02 -07:00
SZEDER Gábor eb7cc5bc80 t5318: use 'test_cmp_bin' to compare commit-graph files
The commit-graph files are binary files, so they should not be
compared with 'test_cmp', because that might cause issues like
crashing[1] or infinite loop[2] on Windows, where 'test_cmp' is a
shell function to deal with random LF-CRLF conversions[3].

Use 'test_cmp_bin' instead.

1 - b93e6e3663 (t5000, t5003: do not use test_cmp to compare binary
    files, 2014-06-04)
2 - f9f3851b4d (t9300: use test_cmp_bin instead of test_cmp to compare
    binary files, 2014-09-12)
3 - 4d715ac05c (Windows: a test_cmp that is agnostic to random LF <>
    CRLF conversions, 2013-10-26)

Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-13 12:07:29 -07:00
Jonathan Tan dade47c06c commit-graph: add repo arg to graph readers
Add a struct repository argument to the functions in commit-graph.h that
read the commit graph. (This commit does not affect functions that write
commit graphs.)

Because the commit graph functions can now read the commit graph of any
repository, the global variable core_commit_graph has been removed.
Instead, the config option core.commitGraph is now read on the first
time in a repository that a commit is attempted to be parsed using its
commit graph.

This commit includes a test that exercises the functionality on an
arbitrary repository that is not the_repository.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-17 15:47:48 -07:00
Derrick Stolee d5d5d7b641 gc: automatically write commit-graph files
The commit-graph file is a very helpful feature for speeding up git
operations. In order to make it more useful, make it possible to
write the commit-graph file during standard garbage collection
operations.

Add a 'gc.commitGraph' config setting that triggers writing a
commit-graph file after any non-trivial 'git gc' command. Defaults to
false while the commit-graph feature matures. We specifically do not
want to have this on by default until the commit-graph feature is fully
integrated with history-modifying features like shallow clones.

Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:29:10 -07:00
Derrick Stolee 59fb87701f commit-graph: add '--reachable' option
When writing commit-graph files, it can be convenient to ask for all
reachable commits (starting at the ref set) in the resulting file. This
is particularly helpful when writing to stdin is complicated, such as a
future integration with 'git gc'.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:29:10 -07:00
Derrick Stolee e0fd51e1d7 fsck: verify commit-graph
If core.commitGraph is true, verify the contents of the commit-graph
during 'git fsck' using the 'git commit-graph verify' subcommand. Run
this check on all alternates, as well.

We use a new process for two reasons:

1. The subcommand decouples the details of loading and verifying a
   commit-graph file from the other fsck details.

2. The commit-graph verification requires the commits to be loaded
   in a specific order to guarantee we parse from the commit-graph
   file for some objects and from the object database for others.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:29:10 -07:00
Derrick Stolee 41df0e307f commit-graph: verify contents match checksum
The commit-graph file ends with a SHA1 hash of the previous contents. If
a commit-graph file has errors but the checksum hash is correct, then we
know that the problem is a bug in Git and not simply file corruption
after-the-fact.

Compute the checksum right away so it is the first error that appears,
and make the message translatable since this error can be "corrected" by
a user by simply deleting the file and recomputing. The rest of the
errors are useful only to developers.

Be sure to continue checking the rest of the file data if the checksum
is wrong. This is important for our tests, as we break the checksum as
we modify bytes of the commit-graph file.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:29:10 -07:00
Derrick Stolee 437787ae1b commit-graph: test for corrupted octopus edge
The commit-graph file has an extra chunk to store the parent int-ids for
parents beyond the first parent for octopus merges. Our test repo has a
single octopus merge that we can manipulate to demonstrate the 'verify'
subcommand detects incorrect values in that chunk.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:29:10 -07:00
Derrick Stolee 88968ebf86 commit-graph: verify commit date
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:29:10 -07:00
Derrick Stolee 1373e547f7 commit-graph: verify generation number
While iterating through the commit parents, perform the generation
number calculation and compare against the value stored in the
commit-graph.

The tests demonstrate that having a different set of parents affects
the generation number calculation, and this value propagates to
descendants. Hence, we drop the single-line condition on the output.

Since Git will ship with the commit-graph feature without generation
numbers, we need to accept commit-graphs with all generation numbers
equal to zero. In this case, ignore the generation number calculation.

However, verify that we should never have a mix of zero and non-zero
generation numbers. Create a test that sets one commit to generation
zero and all following commits report a failure as they have non-zero
generation in a file that contains generation number zero.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:29:10 -07:00
Derrick Stolee 53614b1351 commit-graph: verify parent list
The commit-graph file stores parents in a two-column portion of the
commit data chunk. If there is only one parent, then the second column
stores 0xFFFFFFFF to indicate no second parent.

The 'verify' subcommand checks the parent list for the commit loaded
from the commit-graph and the one parsed from the object database. Test
these checks for corrupt parents, too many parents, and wrong parents.

Add a boundary check to insert_parent_or_die() for when the parent
position value is out of range.

The octopus merge will be tested in a later commit.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:29:10 -07:00
Derrick Stolee 2e3c07378f commit-graph: verify root tree OIDs
The 'verify' subcommand must compare the commit content parsed from the
commit-graph against the content in the object database. Use
lookup_commit() and parse_commit_in_graph_one() to parse the commits
from the graph and compare against a commit that is loaded separately
and parsed directly from the object database.

Add checks for the root tree OID.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:29:10 -07:00
Derrick Stolee 96af91d410 commit-graph: verify objects exist
In the 'verify' subcommand, load commits directly from the object
database to ensure they exist. Parse by skipping the commit-graph.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:27:05 -07:00
Derrick Stolee 9bda846789 commit-graph: verify corrupt OID fanout and lookup
In the commit-graph file, the OID fanout chunk provides an index into
the OID lookup. The 'verify' subcommand should find incorrect values
in the fanout.

Similarly, the 'verify' subcommand should find out-of-order values in
the OID lookup.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:27:05 -07:00
Derrick Stolee 2bd0365f37 commit-graph: verify required chunks are present
The commit-graph file requires the following three chunks:

* OID Fanout
* OID Lookup
* Commit Data

If any of these are missing, then the 'verify' subcommand should
report a failure. This includes the chunk IDs malformed or the
chunk count is truncated.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:27:05 -07:00
Derrick Stolee d9b9f8a6fd commit-graph: verify catches corrupt signature
This is the first of several commits that add a test to check that
'git commit-graph verify' catches corruption in the commit-graph
file. The first test checks that the command catches an error in
the file signature. This is a check that exists in the existing
commit-graph reading code.

Add a helper method 'corrupt_graph_and_verify' to the test script
t5318-commit-graph.sh. This helper corrupts the commit-graph file
at a certain location, runs 'git commit-graph verify', and reports
the output to the 'err' file. This data is filtered to remove the
lines added by 'test_must_fail' when the test is run verbosely.
Then, the output is checked to contain a specific error message.

Most messages from 'git commit-graph verify' will not be marked
for translation. There will be one exception: the message that
reports an invalid checksum will be marked for translation, as that
is the only message that is intended for a typical user.

Helped-by: Szeder Gábor <szeder.dev@gmail.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:27:05 -07:00
Derrick Stolee 283e68c72f commit-graph: add 'verify' subcommand
If the commit-graph file becomes corrupt, we need a way to verify
that its contents match the object database. In the manner of
'git fsck' we will implement a 'git commit-graph verify' subcommand
to report all issues with the file.

Add the 'verify' subcommand to the 'commit-graph' builtin and its
documentation. The subcommand is currently a no-op except for
loading the commit-graph into memory, which may trigger run-time
errors that would be caught by normal use. Add a simple test that
ensures the command returns a zero error code.

If no commit-graph file exists, this is an acceptable state. Do
not report any errors.

Helped-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:27:05 -07:00
Derrick Stolee 55abcb417b t5318-commit-graph.sh: use core.commitGraph
The commit-graph tests should be checking that normal Git operations
succeed and have matching output with and without the commit-graph
feature enabled. However, the test was toggling 'core.graph' instead
of the correct 'core.commitGraph' variable.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-27 10:27:04 -07:00
Derrick Stolee 7adf526670 merge: check config before loading commits
Now that we use generation numbers from the commit-graph, we must
ensure that all commits that exist in the commit-graph are loaded
from that file instead of from the object database. Since the
commit-graph file is only checked if core.commitGraph is true, we
must check the default config before we load any commits.

In the merge builtin, the config was checked after loading the HEAD
commit. This was due to the use of the global 'branch' when checking
merge-specific config settings.

Move the config load to be between the initialization of 'branch' and
the commit lookup.

Without this change, a fast-forward merge would hit a BUG("bad
generation skip") statement in commit.c during paint_down_to_common().
This is because the HEAD commit would be loaded with "infinite"
generation but then reached by commits with "finite" generation
numbers.

Add a test to t5318-commit-graph.sh that exercises this code path to
prevent a regression.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-22 12:36:34 +09:00
Derrick Stolee 7547b95b4f commit-graph: implement "--append" option
Teach git-commit-graph to add all commits from the existing
commit-graph file to the file about to be written. This should be
used when adding new commits without performing garbage collection.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-11 10:43:02 +09:00
Derrick Stolee 3d5df01b5e commit-graph: build graph from starting commits
Teach git-commit-graph to read commits from stdin when the
--stdin-commits flag is specified. Commits reachable from these
commits are added to the graph. This is a much faster way to construct
the graph than inspecting all packed objects, but is restricted to
known tips.

For the Linux repository, 700,000+ commits were added to the graph
file starting from 'master' in 7-9 seconds, depending on the number
of packfiles in the repo (1, 24, or 120).

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-11 10:43:02 +09:00
Derrick Stolee 049d51a2bb commit-graph: read only from specific pack-indexes
Teach git-commit-graph to inspect the objects only in a certain list
of pack-indexes within the given pack directory. This allows updating
the commit graph iteratively.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-11 10:43:02 +09:00
Derrick Stolee 177722b344 commit: integrate commit graph with commit parsing
Teach Git to inspect a commit graph file to supply the contents of a
struct commit when calling parse_commit_gently(). This implementation
satisfies all post-conditions on the struct commit, including loading
parents, the root tree, and the commit date.

If core.commitGraph is false, then do not check graph files.

In test script t5318-commit-graph.sh, add output-matching conditions on
read-only graph operations.

By loading commits from the graph instead of parsing commit buffers, we
save a lot of time on long commit walks. Here are some performance
results for a copy of the Linux repository where 'master' has 678,653
reachable commits and is behind 'origin/master' by 59,929 commits.

| Command                          | Before | After  | Rel % |
|----------------------------------|--------|--------|-------|
| log --oneline --topo-order -1000 |  8.31s |  0.94s | -88%  |
| branch -vv                       |  1.02s |  0.14s | -86%  |
| rev-list --all                   |  5.89s |  1.07s | -81%  |
| rev-list --all --objects         | 66.15s | 58.45s | -11%  |

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-11 10:43:02 +09:00
Derrick Stolee 2a2e32bdc5 commit-graph: implement git commit-graph read
Teach git-commit-graph to read commit graph files and summarize their contents.

Use the read subcommand to verify the contents of a commit graph file in the
tests.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-11 10:43:01 +09:00
Derrick Stolee f237c8b6fe commit-graph: implement git-commit-graph write
Teach git-commit-graph to write graph files. Create new test script to verify
this command succeeds without failure.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-02 14:27:38 -07:00