1BISECT_PERL_USING_GIT(1U)ser Contributed Perl DocumentatiBoInSECT_PERL_USING_GIT(1)
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6 bisect_perl_using_git - Help you to bisect Perl
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9 bisect_perl_using_git helps you to bisect Perl. This helps you to find
10 at what commit a change happened in Perl. You can check for file
11 addition and removal - it checks out various commits of Perl and finds
12 out which change was involved. You can also check for a difference in
13 Perl evalutation, in which case it will check out various commits of
14 Perl, compile them and finds out which change was involved - this is
15 more CPU intensive and you must install ccache.
16 First you must download the current Git repository of Perl, so execute
18 something like the following:
19 mkdir git
21 cd git
22 git clone git://perl5.git.perl.org/perl.git perl-git
23 cd perl-git
24 Now, I happen to know that the autodie pragma was added sometime in
26 December 2008, but I would like to know which commit. Let's find out
27 some commits at the beginning and the end of that month, and see when
28 lib/autodie.pm was added:
29 # git log --before=2008-12-01 -n 1
31 # 1409bc0658469580630ba458c85fe9cc3cb2d78c
32 # git log --before=2008-12-31 -n 1
33 # 675b0f774d374f6951c02c6463c64a746ad46acd
34 git bisect reset
35 git bisect start
36 git bisect good 1409bc0658469580630ba458c85fe9cc3cb2d78c
37 git bisect bad 675b0f774d374f6951c02c6463c64a746ad46acd
38 # Bisecting: 114 revisions left to test after this
39 git bisect run bisect_perl_using_git --action file_added \
40 --filename lib/autodie.pm
41 # ... after checking out 10 trees and about 10 seconds, it says:
42 # 0b09a93a0cec34bc5d1740400c4ed9500d2f1dbe is first bad commit
43 # commit 0b09a93a0cec34bc5d1740400c4ed9500d2f1dbe
44 # Author: Paul Fenwick <pjf@perltraining.com.au>
45 # Date: Sat Dec 20 22:21:02 2008 +0900
46 #
47 # git-flavoured autodie 1.997 patch
48 # G'day p5p,
49 # ...
50 git bisect reset
51 Sometime after June 2009, ext/Storable/MANIFEST was removed from Perl.
53 Let's find out which commit removed it:
54 # git log --before=2009-06-01 -n 1
56 # 20f91e418dfa8bdf6cf78614bfebebc28a7613ee
57 git bisect reset
58 git bisect start
59 git bisect good 20f91e418dfa8bdf6cf78614bfebebc28a7613ee
60 git bisect bad HEAD
61 # Bisecting: 266 revisions left to test after this
62 git bisect run bisect_perl_using_git --action file_removed \
63 --filename ext/Storable/MANIFEST
64 # ... after checking out 11 trees and about 10 seconds, it says:
65 # 2868e48536e3f471e5ba483466cc1bc53caff5a is first bad commit
66 # commit e2868e48536e3f471e5ba483466cc1bc53caff5a
67 # Author: David Mitchell <davem@iabyn.com>
68 # Date: Fri Jun 12 17:24:43 2009 +0100
69 #
70 # remove ext/Storable/MANIFEST; its out of date related to CPAN
71 # and for most dual-life modules we don't bother including it in blead
72 # ...
73 git bisect reset
74 Now for a real bug report, where some code that works in Perl 5.8.8 and
76 should work in Perl 5.10.0 but does not:
77 http://rt.perl.org/rt3/Public/Bug/Display.html?id=62056
79 We create a ~/testcase.pl which contains the following:
81 #!perl
83 use strict;
84 use warnings;
85 use charnames ':full';
86 my $x;
87 m/$x\N{START OF HEADING}/
88 And then run:
90 git bisect reset
92 git bisect start
93 git bisect good perl-5.8.8
94 git bisect bad perl-5.10.0
95 # Bisecting: 4041 revisions left to test after this
96 git bisect run bisect_perl_using_git --action perl_fails \
97 --filename ~/testcase.pl
98 # ... after checking out 16 trees and about one hour, it says:
99 # fc8cd66c26827f6c2ee1aa00ab2d3b3c320a4a28 is first bad commit
100 # commit fc8cd66c26827f6c2ee1aa00ab2d3b3c320a4a28
101 # Author: Yves Orton <demerphq@gmail.com>
102 # Date: Tue Sep 19 03:37:19 2006 +0200
103 #
104 # Re: \N{...} in regular expression [PATCH]
105 # ...
106 git bisect reset
107
109 Leon Brocard, "<acme@astray.com>"
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112 Copyright (C) 2009, Leon Brocard
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115 This module is free software; you can redistribute it or modify it
116 under the same terms as Perl itself.
117perl v5.38.0 2023-07-20 BISECT_PERL_USING_GIT(1)