git/Documentation/CodingGuidelines, branch v2.40.2

Merge branch 'ab/doc-synopsis-and-cmd-usage'

2022-10-28T18:26:54Z

The short-help text shown by "git cmd -h" and the synopsis text shown at the beginning of "git help cmd" have been made more consistent. * ab/doc-synopsis-and-cmd-usage: (34 commits) tests: assert consistent whitespace in -h output tests: start asserting that *.txt SYNOPSIS matches -h output doc txt & -h consistency: make "worktree" consistent worktree: define subcommand -h in terms of command -h reflog doc: list real subcommands up-front doc txt & -h consistency: make "commit" consistent doc txt & -h consistency: make "diff-tree" consistent doc txt & -h consistency: use "[...]" for "zero or more" doc txt & -h consistency: make "annotate" consistent doc txt & -h consistency: make "stash" consistent doc txt & -h consistency: add missing options doc txt & -h consistency: use "git foo" form, not "git-foo" doc txt & -h consistency: make "bundle" consistent doc txt & -h consistency: make "read-tree" consistent doc txt & -h consistency: make "rerere" consistent doc txt & -h consistency: add missing options and labels doc txt & -h consistency: make output order consistent doc txt & -h consistency: add or fix optional "--" syntax doc txt & -h consistency: fix mismatching labels doc SYNOPSIS & -h: use "-" to separate words in labels, not "_" ...

Merge branch 'ab/coding-guidelines-c99'

2022-10-19T22:38:05Z

Update CodingGuidelines to clarify what features to use and avoid in C99. * ab/coding-guidelines-c99: CodingGuidelines: recommend against unportable C99 struct syntax CodingGuidelines: mention C99 features we can't use CodingGuidelines: allow declaring variables in for loops CodingGuidelines: mention dynamic C99 initializer elements CodingGuidelines: update for C99

CodingGuidelines: update and clarify command-line conventions

2022-10-13T16:32:54Z

Edit the section which explains how to create a good SYNOPSIS section for clarity and accuracy, it was mostly introduced in c455bd8950e (CodingGuidelines: Add a section on writing documentation, 2010-11-04): * Change "extra" example to "file", which now naturally follows from previous "..." example (one or more) to "[...]" (zero or more). * Explain how we prefer spacing around "[]()" tokens and "|" alternatives, this is not a new policy, but just codifies what's already the pattern in the most wide use in the documentation. Having a space around " | " for flags, but not for flag values is inconsistent, but this style guide codifies existing patterns. Grepping shows that we don't have any instance matching the second "Don't" example: git grep -E -h -o '=\([^)]+\)' -- builtin Documentation/ Signed-off-by: Ævar Arnfjörð Bjarmason Signed-off-by: Junio C Hamano

CodingGuidelines: recommend against unportable C99 struct syntax

2022-10-11T15:55:01Z

Per 33665d98e6b (reftable: make assignments portable to AIX xlc v12.01, 2022-03-28) forms like ".a.b = *c" can be replaced by using ".a = { .b = *c }" instead. We'll probably allow these sooner than later, but since the workaround is trivial let's note it among the C99 features we'd like to hold off on for now. Signed-off-by: Ævar Arnfjörð Bjarmason Signed-off-by: Junio C Hamano

CodingGuidelines: mention C99 features we can't use

2022-10-10T20:41:12Z

The C99 section of the CodingGuidelines is a good overview of what we can use, but is sorely lacking in what we can't use. Something that comes up occasionally is the portability of %z. Per [1] we couldn't use it for the longest time due to MSVC not supporting it, but nowadays by requiring C99 we rely on the MSVC version that does, but we can't use it yet because a C library that MinGW uses doesn't support it. 1. https://lore.kernel.org/git/a67e0fd8-4a14-16c9-9b57-3430440ef93c@gmail.com/ Signed-off-by: Ævar Arnfjörð Bjarmason Signed-off-by: Junio C Hamano

CodingGuidelines: allow declaring variables in for loops

2022-10-10T20:41:11Z

Since 44ba10d6712 (revision: use C99 declaration of variable in for() loop, 2021-11-14) released with v2.35.0 we've had a variable declared with in a for loop. Since then we've had inadvertent follow-ups to that with at least cb2607759e2 (merge-ort: store more specific conflict information, 2022-06-18) released with v2.38.0. As November 2022 is within the window of this upcoming release, let's update the guideline to allow this. We can have the promised "revisit" discussion while this patch cooks, and drop it if it turns out that it is still premature, which is not expected to happen at this moment. Signed-off-by: Ævar Arnfjörð Bjarmason Signed-off-by: Junio C Hamano

CodingGuidelines: mention dynamic C99 initializer elements

2022-10-10T20:41:11Z

The first use of variables in initializer elements appears to have been 2b6854c863a (Cleanup variables in cat-file, 2007-04-21) released with v1.5.2. Some of those caused portability issues, and e.g. that "cat-file" use was changed in 66dbfd55e38 (Rewrite dynamic structure initializations to runtime assignment, 2010-05-14) which went out with v1.7.2. But curiously 66dbfd55e38 missed some of them, e.g. an archive.c use added in d5f53d6d6f2 (archive: complain about path specs that don't match anything, 2009-12-12), and another one in merge-index.c (later builtin/merge-index.c) in 0077138cd9d (Simplify some instances of run_command() by using run_command_v_opt()., 2009-06-08). As far as I can tell there's been no point since 2b6854c863a in 2007 where a compiler that didn't support this has been able to compile git. Presumably 66dbfd55e38 was an attempt to make headway with wider portability that ultimately wasn't completed. In any case, we are thoroughly reliant on this syntax at this point, so let's update the guidelines, see https://lore.kernel.org/git/xmqqy1tunjgp.fsf@gitster.g/ for the initial discussion. Signed-off-by: Ævar Arnfjörð Bjarmason Signed-off-by: Junio C Hamano

CodingGuidelines: update for C99

2022-10-10T20:41:11Z

Since 7bc341e21b5 (git-compat-util: add a test balloon for C99 support, 2021-12-01) we've had a hard dependency on C99, but the prose in CodingGuidelines was written under the assumption that we were using C89 with a few C99 features. As the updated prose notes we'd still like to hold off on novel C99 features, but let's make it clear that we target that C version, and then enumerate new C99 features that are safe to use. Signed-off-by: Ævar Arnfjörð Bjarmason Signed-off-by: Junio C Hamano

CodingGuidelines: allow grep -E

2022-09-21T18:00:18Z

Despite forbidden by CodingGuidelines, our usage of 'grep -E' has been increased over the years, and noone has come and complained. Let's lift the restriction. Signed-off-by: Đoàn Trần Công Danh Signed-off-by: Junio C Hamano

Documentation: fix various repeat word typos

2022-09-12T18:04:55Z

Inspired by 24966cd982 ("doc: fix repeated words", 08-09-2019), I ran "egrep -R "\<([a-zA-Z]+)\> \<\1\>" ./Documentation/*" to find current cases of repeated words such as "the the" that were quite clearly typos. There were many false positives reported, such as "really really" or valid uses of "that that" which I left alone. Signed-off-by: Jacob Stopak Signed-off-by: Junio C Hamano