git/contrib/diff-highlight, branch v2.48.2

Require Perl 5.26.0

2024-10-23T20:16:36Z

Our platform support policy states that we require "versions of dependencies which are generally accepted as stable and supportable, e.g., in line with the version used by other long-term-support distributions". Of Debian, Ubuntu, RHEL, and SLES, the four most common distributions that provide LTS versions, the version with mainstream long-term security support with the oldest Perl is 5.26.0 in SLES 15.6. This is a major upgrade, since Perl 5.8.1, according to the Perl documentation, was released in September of 2003. It brings a lot of new features that we can choose to use, such as s///r to return the modified string, the postderef functionality, and subroutine signatures, although the latter was still considered experimental until 5.36. This change was made with the following one-liner, which intentionally excludes modifying the vendored modules we include to avoid conflicts: git grep -l 'use 5.008001' | grep -v 'LoadCPAN/' | xargs perl -pi -e 's/use 5.008001/require v5.26/' Use require instead of use to avoid changing the behavior as the latter enables features and the former does not. Signed-off-by: brian m. carlson Signed-off-by: Taylor Blau

perl: bump the required Perl version to 5.8.1 from 5.8.0

2023-11-16T22:26:32Z

The following commit will make use of a Getopt::Long feature which is only present in Perl >= 5.8.1. Document that as the minimum version we support. Many of our Perl scripts will continue to run with 5.8.0 but this change allows us to adjust them as needed without breaking any promises to our users. The Perl requirement was last changed in d48b284183 (perl: bump the required Perl version to 5.8 from 5.6.[21], 2010-09-24). At that time, 5.8.0 was 8 years old. It is now over 21 years old. Signed-off-by: Todd Zullinger Signed-off-by: Junio C Hamano

diff-highlight: correctly match blank lines for flush

2020-09-22T05:33:28Z

We try to flush the output from diff-highlight whenever we see a blank line. That lets you see the output for each commit as soon as it is generated, even if Git is still chugging away at a diff, or traversing to find the next commit. However, our "blank line" match checks length($_). That won't ever be true, because we haven't chomped the line ending. As a result, we never flush. Instead, let's use a simple regex which handles line endings in with the end-of-line marker. This has been broken since the initial version in 927a13fe87 (contrib: add diff highlight script, 2011-10-18). Probably nobody noticed because: - most output is big enough, or comes fast enough, that it flushes anyway. And it can be difficult to notice the difference between "show a commit, then pause" and "pause, then show two commits". I only noticed because I was viewing "git log" output on a repo with a very slow textconv filter. - if stdout is going to the terminal (and not another pager like less), then the flush isn't necessary. So any manual testing would show it appearing to work. You can easily see the difference with something like: echo '* diff=slow' >>.gitattributes git -c diff.slow.textconv='sleep 1; cat' \ -c pager.log='diff-highlight | less' \ log -p That should generate one commit every second or so (more if it touches multiple files), but without this patch it waits for many seconds before generating several pages of output. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

diff-highlight: fix a whitespace nit

2019-10-15T05:08:37Z

This changes the indent from "" to "" so that the statement lines up with the rest of the block. Signed-off-by: Norman Rasmussen Acked-by: Jeff King Signed-off-by: Junio C Hamano

diff-highlight: use correct /dev/null for UNIX and Windows

2019-05-09T03:18:44Z

Use File::Spec->devnull() for output redirection to avoid messages when Windows version of Perl is first in path. The message 'The system cannot find the path specified.' is displayed each time git is run to get colors. Signed-off-by: Chris. Webster Signed-off-by: Junio C Hamano

diff-highlight: detect --graph by indent

2018-03-21T17:24:19Z

This patch fixes a corner case where diff-highlight may scramble some diffs when combined with --graph. Commit 7e4ffb4c17 (diff-highlight: add support for --graph output, 2016-08-29) taught diff-highlight to skip past the graph characters at the start of each line with this regex: ($COLOR?\|$COLOR?\s+)* I.e., any series of pipes separated by and followed by arbitrary whitespace. We need to match more than just a single space because the commit in question may be indented to accommodate other parts of the graph drawing. E.g.: * commit 1234abcd | ... | diff --git ... has only a single space, but for the last commit before a fork: | | | | * | commit 1234abcd | |/ ... | | diff --git the diff lines have more spaces between the pipes and the start of the diff. However, when we soak up all of those spaces with the $GRAPH regex, we may accidentally include the leading space for a context line. That means we may consider the actual contents of a context line as part of the diff syntax. In other words, something like this: normal context line -old line +new line -this is a context line with a leading dash would cause us to see that final context line as a removal line, and we'd end up showing the hunk in the wrong order: normal context line -old line -this is a context line with a leading dash +new line Instead, let's a be a little more clever about parsing the graph. We'll look for the actual "*" line that marks the start of a commit, and record the indentation we see there. Then we can skip past that indentation when checking whether the line is a hunk header, removal, addition, etc. There is one tricky thing: the indentation in bytes may be different for various lines of the graph due to coloring. E.g., the "*" on a commit line is generally shown without color, but on the actual diff lines, it will be replaced with a colorized "|" character, adding several bytes. We work around this here by counting "visible" bytes. This is unfortunately a bit more expensive, making us about twice as slow to handle --graph output. But since this is meant to be used interactively anyway, it's tolerably fast (and the non-graph case is unaffected). One alternative would be to search for hunk header lines and use their indentation (since they'd have the same colors as the diff lines which follow). But that just opens up different corner cases. If we see: | | @@ 1,2 1,3 @@ we cannot know if this is a real diff that has been indented due to the graph, or if it's a context line that happens to look like a diff header. We can only be sure of the indent on the "*" lines, since we know those don't contain arbitrary data (technically the user could include a bunch of extra indentation via --format, but that's rare enough to disregard). Reported-by: Phillip Wood Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

diff-highlight: use flush() helper consistently

2018-03-21T17:24:19Z

The current flush() helper only shows the queued diff but does not clear the queue. This is conceptually a bug, but it works because we only call it once at the end of the program. Let's teach it to clear the queue, which will let us use it in more places (one for now, but more in future patches). Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

diff-highlight: test graphs with --color

2018-03-21T17:24:19Z

Our tests send git's output directly to files or pipes, so there will never be any color. Let's do at least one --color test to make sure that we can handle this case (which we currently can, but will be an easy thing to mess up when we touch the graph code in a future patch). We'll just cover the --graph case, since this is much more complex than the earlier cases (i.e., if it manages to highlight, then the non-graph case definitely would). Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

diff-highlight: test interleaved parallel lines of history

2018-03-21T17:24:19Z

The graph test in t9400 covers the case of two simultaneous branches, but all of the commits during this time are on the right-hand branch. So we test a graph structure like: | | | * commit ... | | but we never see the reverse, a commit on the left-hand branch: | | * | commit ... | | Since this is an easy thing to get wrong when touching the graph-matching code, let's cover it by adding one more commit with its timestamp interleaved with the other branch. Note that we need to pass --date-order to convince Git to show it this way (since --topo-order tries to keep lines of history separate). Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

diff-highlight: prefer "echo" to "cat" in tests

2018-03-21T17:24:19Z

We generate a bunch of one-line files whose contents match their names, and then generate our commits by cat-ing those files. Let's just echo the contents directly, which saves some processes. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano