git/diff-merges.c, branch gitk-resize-error

diff-index: restore -c/--cc options handling

2021-09-07T18:11:35Z

This fixes 19b2517f (diff-merges: move specific diff-index "-m" handling to diff-index, 2021-05-21). That commit disabled handling of all diff for merges options in diff-index on an assumption that they are unused. However, it later appeared that -c and --cc, even though undocumented and not being covered by tests, happen to have had particular effect on diff-index output. Restore original -c/--cc options handling by diff-index. Signed-off-by: Sergey Organov Signed-off-by: Junio C Hamano

Revert 'diff-merges: let "-m" imply "-p"'

2021-08-09T20:52:01Z

This reverts commit f5bfcc823ba242a46e20fb6f71c9fbf7ebb222fe, which made "git log -m" imply "--patch" by default. The logic was that "-m", which makes diff generation for merges perform a diff against each parent, has no use unless I am viewing the diff, so we could save the user some typing by turning on display of the resulting diff automatically. That wasn't expected to adversely affect scripts because scripts would either be using a command like "git diff-tree" that already emits diffs by default or would be combining -m with a diff generation option such as --name-status. By saving typing for interactive use without adversely affecting scripts in the wild, it would be a pure improvement. The problem is that although diff generation options are only relevant for the displayed diff, a script author can imagine them affecting path limiting. For example, I might run git log -w --format=%H -- README hoping to list commits that edited README, excluding whitespace-only changes. In fact, a whitespace-only change is not TREESAME so the use of -w here has no effect (since we don't apply these diff generation flags to the diff_options struct rev_info::pruning used for this purpose), but the documentation suggests that it should work Suppose you specified foo as the . We shall call commits that modify foo !TREESAME, and the rest TREESAME. (In a diff filtered for foo, they look different and equal, respectively.) and a script author who has not tested whitespace-only changes wouldn't notice. Similarly, a script author could include git log -m --first-parent --format=%H -- README to filter the first-parent history for commits that modified README. The -m is a no-op but it reflects the script author's intent. For example, until 1e20a407fe2 (stash list: stop passing "-m" to "git log", 2021-05-21), "git stash list" did this. As a result, we can't safely change "-m" to imply "-p" without fear of breaking such scripts. Restore the previous behavior. Noticed because Rust's src/bootstrap/bootstrap.py made use of this same construct: https://github.com/rust-lang/rust/pull/87513. That script has been updated to omit the unnecessary "-m" option, but we can expect other scripts in the wild to have similar expectations. Signed-off-by: Jonathan Nieder Signed-off-by: Junio C Hamano

diff-merges: let "-m" imply "-p"

2021-05-21T00:24:14Z

Fix long standing inconsistency between -c/--cc that do imply -p on one side, and -m that did not imply -p on the other side. Change corresponding test accordingly, as "log -m" output should now match one from "log -m -p", rather than from just "log". Change documentation accordingly. NOTES: After this patch git log -m produces diffs without need to provide -p as well, that improves both consistency and usability. It gets even more useful if one sets "log.diffMerges" configuration variable to "first-parent" to force -m produce usual diff with respect to first parent only. This patch, however, does not change behavior when specific diff format is explicitly provided on the command-line, so that commands like git log -m --raw git log -m --stat are not affected, nor does it change commands where specific diff format is active by default, such as: git diff-tree -m It's also worth to be noticed that exact historical semantics of -m is still provided by --diff-merges=separate. Signed-off-by: Sergey Organov Signed-off-by: Junio C Hamano

diff-merges: rename "combined_imply_patch" to "merges_imply_patch"

2021-05-21T00:24:14Z

This is refactoring change in preparation for the next commit that will let -m imply -p. The old name doesn't match the intention to let not only -c/-cc imply -p, but also -m, that is not a "combined" format, so we rename the flag accordingly. Signed-off-by: Sergey Organov Signed-off-by: Junio C Hamano

diff-merges: move specific diff-index "-m" handling to diff-index

2021-05-21T00:24:14Z

Move specific handling of "-m" for diff-index to diff-index.c, so diff-merges is left to handle only diff for merges options. Being a better design by itself, this is especially essential in preparation for letting -m imply -p, as "diff-index -m" obviously should not imply -p, as it's entirely unrelated. To handle this, in addition to moving specific diff-index "-m" code out of diff-merges, we introduce new diff_merges_suppress_options_parsing() and call it before generic options processing in cmd_diff_index(). This new diff_merges_suppress_options_parsing() could then be reused and called before invocations of setup_revisions() for other commands that don't need --diff-merges options, but that's outside of the scope of these patch series. Signed-off-by: Sergey Organov Signed-off-by: Junio C Hamano

diff-merges: introduce log.diffMerges config variable

2021-04-17T06:38:35Z

New log.diffMerges configuration variable sets the format that --diff-merges=on will be using. The default is "separate". t4013: add the following tests for log.diffMerges config: * Test that wrong values are denied. * Test that the value of log.diffMerges properly affects both --diff-merges=on and -m. t9902: fix completion tests for log.d* to match log.diffMerges. Added documentation for log.diffMerges. Signed-off-by: Sergey Organov Signed-off-by: Junio C Hamano

diff-merges: adapt -m to enable default diff format

2021-04-17T06:38:35Z

Let -m option (and --diff-merges=m) enable the default format instead of "separate", to be able to tune it with log.diffMerges option. Signed-off-by: Sergey Organov Signed-off-by: Junio C Hamano

diff-merges: refactor set_diff_merges()

2021-04-17T06:38:35Z

Split set_diff_merges() into separate parsing and execution functions, the former to be reused for parsing of configuration values later in the patch series. Signed-off-by: Sergey Organov Signed-off-by: Junio C Hamano

diff-merges: introduce --diff-merges=on

2021-04-17T06:38:35Z

Introduce the notion of default diff format for merges, and the option "on" to select it. The default format is "separate" and can't yet be changed, so effectively "on" is just a synonym for "separate" for now. Add corresponding test to t4013. This is in preparation for introducing log.diffMerges configuration option that will let --diff-merges=on to be configured to any supported format. Signed-off-by: Sergey Organov Signed-off-by: Junio C Hamano

diff-merges: add '--diff-merges=1' as synonym for 'first-parent'

2020-12-21T21:47:32Z

As we now have --diff-merges={m|c|cc}, add --diff-merges=1 as synonym for --diff-merges=first-parent, to have shorter mnemonics for it as well. Signed-off-by: Sergey Organov Signed-off-by: Junio C Hamano