[PATCH 2/2] object name: introduce '^{/!<negative pattern>}' notation
- From
Will Palmer <wmpalmer@gmail.com>
- Date
- Jun 3, 2015, 20:54 UTC
- Message-ID
- <1433364854-30088-3-git-send-email-wmpalmer@gmail.com>
- In-Reply-To
- <1433364854-30088-1-git-send-email-wmpalmer@gmail.com>
To name a commit, you can now say
$ git rev-parse HEAD^{/!foo}and it will return the hash of the first commit reachable from HEAD, whose commit message does not contain "foo".
Since the ability to reference a commit by "name" was introduced (way back in 1.5, in 364d3e6), with the across-all-refs syntax of ':/foo', there has been a note in the documentation indicating that a leading exclamation mark was "reserved for now" (unless followed immediately be another exclamation mark.)
At the time, this was sensible: we didn't get the '^{/foo}' flavour until sometime around 1.7.4 (41cd797) , so while a "negative search" was a foreseeable feature, it wouldn't have made much sense to apply one across all refs, as the result would have been essentially random.
These days, a negative pattern can make sense. In particular, if you tend to use a rebase-heavy workflow with many "work in progress" commits, it may be useful to diff or rebase against the latest "not work-in-progress" commit. That sort of thing now possible, via commands such as:
$ git rebase -i @^{/!^WIP}Perhaps notably, the "special case" for the empty pattern has been extended to handle the empty negative pattern - which never matches, to continue to ensure that an empty pattern never reaches the real regexp code, as per notes in 4322842 "get_sha1: handle special case $commit^{/}"
Signed-off-by: Will Palmer <wmpalmer@gmail.com> --- Documentation/revisions.txt | 7 ++++--- sha1_name.c | 22 ++++++++++++++++------ t/t1511-rev-parse-caret.sh | 32 +++++++++++++++++++++++++++++--- 3 files changed, 49 insertions(+), 12 deletions(-)
diff --git a/Documentation/revisions.txt b/Documentation/revisions.txt index 0796118..6a6b8b9 100644 --- a/Documentation/revisions.txt +++ b/Documentation/revisions.txt @@ -151,9 +151,10 @@ existing tag object. A colon, followed by a slash, followed by a text, names a commit whose commit message matches the specified regular expression. This name returns the youngest matching commit which is - reachable from any ref. If the commit message starts with a - '!' you have to repeat that; the special sequence ':/!', - followed by something else than '!', is reserved for now. + reachable from any ref. To name a commit whose commit message does not + match the specified regular expression, begin the pattern-part with a + '!', e.g. ':/!foo'. If the commit message you wish to match starts with + a '!' you have to repeat that. The regular expression can match any part of the commit message. To match messages starting with a string, one can use e.g. ':/^foo'. diff --git a/sha1_name.c b/sha1_name.c index 46218ba..3d50dc9 100644 --- a/sha1_name.c +++ b/sha1_name.c @@ -737,11 +737,15 @@ static int peel_onion(const char *name, int len, unsigned char *sha1) /* * $commit^{/}. Some regex implementation may reject. - * We don't need regex anyway. '' pattern always matches. + * We don't need regex anyway. '' pattern always matches, + * and '!' pattern never matches. */ if (sp[1] == '}') return 0; + if (sp[1] == '!' && sp[2] == '}') + return -1; + prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1)); commit_list_insert((struct commit *)o, &list); ret = get_sha1_oneline(prefix, sha1, list); @@ -825,8 +829,9 @@ static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned l * through history and returning the first commit whose message starts * the given regular expression. * - * For future extension, ':/!' is reserved. If you want to match a message - * beginning with a '!', you have to repeat the exclamation mark. + * For negative-matching, prefix the pattern-part with a '!', like: + * ':/!WIP'. If you want to match a message beginning with a literal + * '!', you heave to repeat the exlamation mark. */ /* Remember to update object flag allocation in object.h */ @@ -855,11 +860,16 @@ static int get_sha1_oneline(const char *prefix, unsigned char *sha1, { struct commit_list *backup = NULL, *l; int found = 0; + int negative = 0; regex_t regex; if (prefix[0] == '!') { - if (prefix[1] != '!') - die ("Invalid search pattern: %s", prefix); + if (prefix[1] != '!') { + negative = 1; + } else if (prefix[1] == '!' && prefix[2] == '!') { + negative = 1; + prefix++; + } prefix++; } @@ -880,7 +890,7 @@ static int get_sha1_oneline(const char *prefix, unsigned char *sha1, continue; buf = get_commit_buffer(commit, NULL); p = strstr(buf, "\n\n"); - matches = p && !regexec(®ex, p + 2, 0, NULL, 0); + matches = p && (negative ^ !regexec(®ex, p + 2, 0, NULL, 0)); unuse_commit_buffer(commit, buf); if (matches) { diff --git a/t/t1511-rev-parse-caret.sh b/t/t1511-rev-parse-caret.sh index 0c46e5c..1d27aca 100755 --- a/t/t1511-rev-parse-caret.sh +++ b/t/t1511-rev-parse-caret.sh @@ -19,13 +19,17 @@ test_expect_success 'setup' ' echo modified >>a-blob && git add -u && git commit -m Modified && + git branch modref && echo changed! >>a-blob && git add -u && git commit -m !Exp && git branch expref && echo changed >>a-blob && git add -u && - git commit -m Changed + git commit -m Changed && + echo changed-again >>a-blob && + git add -u && + git commit -m Changed-again ' test_expect_success 'ref^{non-existent}' ' @@ -84,8 +88,8 @@ test_expect_success 'ref^{/Initial}' ' test_cmp expected actual ' -test_expect_success 'ref^{/!Exp}' ' - test_must_fail git rev-parse master^{/!Exp} +test_expect_success 'ref^{/!}' ' + test_must_fail git rev-parse master^{/!} ' test_expect_success 'ref^{/!!Exp}' ' @@ -94,4 +98,26 @@ test_expect_success 'ref^{/!!Exp}' ' test_cmp expected actual ' +test_expect_success 'ref^{/!.}' ' + test_must_fail git rev-parse master^{/\!.} +' + +test_expect_success 'ref^{/!non-existent}' ' + git rev-parse master >expected && + git rev-parse master^{/\!non-existent} >actual && + test_cmp expected actual +' + +test_expect_success 'ref^{/!Changed}' ' + git rev-parse expref >expected && + git rev-parse master^{/!Changed} >actual && + test_cmp expected actual +' + +test_expect_success 'ref^{/!!!Exp}' ' + git rev-parse modref >expected && + git rev-parse expref^{/!!!Exp} >actual && + test_cmp expected actual +' + test_done
-- 2.3.0.rc1