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[PATCH 02/29] grep & rev-list doc: stop promising libpcre for --perl-regexp

From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date
May 11, 2017, 09:18 UTC
Message-ID
<20170511091829.5634-3-avarab@gmail.com>
In-Reply-To
<20170511091829.5634-1-avarab@gmail.com>

Stop promising in our grep & rev-list options documentation that we're always going to be using libpcre when given the --perl-regexp option.

Instead talk about using "Perl-compatible regular expressions" and using these types of patterns using "a compile-time dependency".

Saying "libpcre" means that we're talking about libpcre.so, which is always going to be v1. This change is part of an ongoing saga to add support for libpcre2, which comes with PCRE v2.

In the future we might use some completely unrelated library to provide perl-compatible regular expression support. By wording the documentation differently and not promising any specific version of PCRE or even PCRE at all we have more wiggle room to change the implementation.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 Documentation/git-grep.txt         | 7 +++++--
 Documentation/rev-list-options.txt | 8 ++++++--
 2 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/Documentation/git-grep.txt b/Documentation/git-grep.txt
index 71f32f3508..5033483db4 100644
--- a/Documentation/git-grep.txt
+++ b/Documentation/git-grep.txt
@@ -161,8 +161,11 @@ OPTIONS
 
 -P::
 --perl-regexp::
-	Use Perl-compatible regexp for patterns. Requires libpcre to be
-	compiled in.
+	Use Perl-compatible regular expressions for patterns.
++
+Support for these types of regular expressions is an optional
+compile-time dependency. If Git wasn't compiled with support for them
+providing this option will cause it to die.
 
 -F::
 --fixed-strings::
diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt
index a02f7324c0..a46f70c2b1 100644
--- a/Documentation/rev-list-options.txt
+++ b/Documentation/rev-list-options.txt
@@ -92,8 +92,12 @@ endif::git-rev-list[]
 	pattern as a regular expression).
 
 --perl-regexp::
-	Consider the limiting patterns to be Perl-compatible regular expressions.
-	Requires libpcre to be compiled in.
+	Consider the limiting patterns to be Perl-compatible regular
+	expressions.
++
+Support for these types of regular expressions is an optional
+compile-time dependency. If Git wasn't compiled with support for them
+providing this option will cause it to die.
 
 --remove-empty::
 	Stop when a given path disappears from the tree.
-- 
2.11.0
Previous: Ævar Arnfjörð BjarmasonNext: Ævar Arnfjörð Bjarmason
Message 2 of 61 in “Easy to review grep & pre-PCRE changes”
  1. 00/29 Easy to review grep & pre-PCRE changesÆvar Arnfjörð Bjarmason, May 11, 2017
  2. 02/29 grep & rev-list doc: stop promising libpcre for --perl-regexpÆvar Arnfjörð Bjarmason, May 11, 2017
  3. 03/29 test-lib: rename the LIBPCRE prerequisite to PCREÆvar Arnfjörð Bjarmason, May 11, 2017
  4. 01/29 Makefile & configure: reword inaccurate comment about PCREÆvar Arnfjörð Bjarmason, May 11, 2017
  5. 04/29 log: add exhaustive tests for pattern style options & configÆvar Arnfjörð Bjarmason, May 11, 2017
  6. Junio C HamanoMay 12, 2017
  7. Ævar Arnfjörð BjarmasonMay 13, 2017
  8. 06/29 grep: add a test for backreferences in PCRE patternsÆvar Arnfjörð Bjarmason, May 11, 2017
  9. 05/29 grep: add a test asserting that --perl-regexp dies when !PCREÆvar Arnfjörð Bjarmason, May 11, 2017
  10. 08/29 grep: add tests for --threads=N and grep.threadsÆvar Arnfjörð Bjarmason, May 11, 2017
  11. Brandon WilliamsMay 11, 2017
  12. Ævar Arnfjörð BjarmasonMay 11, 2017
  13. 09/29 grep: amend submodule recursion test for regex engine testingÆvar Arnfjörð Bjarmason, May 11, 2017
  14. Junio C HamanoMay 12, 2017
  15. Ævar Arnfjörð BjarmasonMay 13, 2017
  16. 10/29 grep: add tests for grep pattern types being passed to submodulesÆvar Arnfjörð Bjarmason, May 11, 2017
  17. 07/29 grep: change non-ASCII -i test to stop using --debugÆvar Arnfjörð Bjarmason, May 11, 2017
  18. Brandon WilliamsMay 11, 2017
  19. Ævar Arnfjörð BjarmasonMay 11, 2017
  20. Brandon WilliamsMay 11, 2017
  21. 12/29 grep: prepare for testing binary regexes containing rx metacharactersÆvar Arnfjörð Bjarmason, May 11, 2017
  22. 13/29 grep: add tests to fix blind spots with \0 patternsÆvar Arnfjörð Bjarmason, May 11, 2017
  23. 14/29 perf: add a GIT_PERF_MAKE_COMMAND for when *_MAKE_OPTS won't doÆvar Arnfjörð Bjarmason, May 11, 2017
  24. 11/29 grep: add a test helper function for less verbose -f \0 testsÆvar Arnfjörð Bjarmason, May 11, 2017
  25. Junio C HamanoMay 12, 2017
  26. Ævar Arnfjörð BjarmasonMay 13, 2017
  27. Junio C HamanoMay 15, 2017
  28. 15/29 perf: emit progress output when unpacking & buildingÆvar Arnfjörð Bjarmason, May 11, 2017
  29. 16/29 perf: add a performance comparison test of grep -G, -E and -PÆvar Arnfjörð Bjarmason, May 11, 2017
  30. 18/29 grep: catch a missing enum in switch statementÆvar Arnfjörð Bjarmason, May 11, 2017
  31. Brandon WilliamsMay 11, 2017
  32. Stefan BellerMay 11, 2017
  33. Ævar Arnfjörð BjarmasonMay 11, 2017
  34. 17/29 perf: add a performance comparison of fixed-string grepÆvar Arnfjörð Bjarmason, May 11, 2017
  35. 19/29 grep: remove redundant regflags assignment under PCREÆvar Arnfjörð Bjarmason, May 11, 2017
  36. 20/29 grep: remove redundant `regflags &= ~REG_EXTENDED` assignmentsÆvar Arnfjörð Bjarmason, May 11, 2017
  37. 21/29 grep: factor test for \0 in grep patterns into a functionÆvar Arnfjörð Bjarmason, May 11, 2017
  38. Brandon WilliamsMay 11, 2017
  39. Ævar Arnfjörð BjarmasonMay 11, 2017
  40. 22/29 grep: change the internal PCRE macro names to be PCRE1Ævar Arnfjörð Bjarmason, May 11, 2017
  41. Brandon WilliamsMay 11, 2017
  42. 23/29 grep: change internal *pcre* variable & function names to be *pcre1*Ævar Arnfjörð Bjarmason, May 11, 2017
  43. 24/29 grep: move two functions to avoid forward declarationÆvar Arnfjörð Bjarmason, May 11, 2017
  44. Brandon WilliamsMay 11, 2017
  45. Ævar Arnfjörð BjarmasonMay 11, 2017
  46. 25/29 test-lib: add a PTHREADS prerequisiteÆvar Arnfjörð Bjarmason, May 11, 2017
  47. 26/29 pack-objects & index-pack: add test for --threads warningÆvar Arnfjörð Bjarmason, May 11, 2017
  48. Brandon WilliamsMay 11, 2017
  49. Ævar Arnfjörð BjarmasonMay 11, 2017
  50. 28/29 grep: given --threads with NO_PTHREADS=YesPlease, warnÆvar Arnfjörð Bjarmason, May 11, 2017
  51. Brandon WilliamsMay 11, 2017
  52. Ævar Arnfjörð BjarmasonMay 11, 2017
  53. Brandon WilliamsMay 11, 2017
  54. C style: use standard style for "TRANSLATORS" commentsÆvar Arnfjörð Bjarmason, May 11, 2017
  55. Jonathan NiederMay 11, 2017
  56. Brandon WilliamsMay 11, 2017
  57. Johannes SixtMay 12, 2017
  58. Jiang XinMay 30, 2017
  59. Junio C HamanoMay 30, 2017
  60. 27/29 pack-objects: fix buggy warning about threadsÆvar Arnfjörð Bjarmason, May 11, 2017
  61. 29/29 grep: assert that threading is enabled when calling grep_{lock,unlock}Ævar Arnfjörð Bjarmason, May 11, 2017

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