diff options
author | NAITOH Jun <naitoh@gmail.com> | 2024-01-13 06:22:32 +0900 |
---|---|---|
committer | Sutou Kouhei <kou@cozmixng.org> | 2024-01-14 22:27:24 +0900 |
commit | 338eb0065bd81ba8ae8b9402abc94804a24594cc (patch) | |
tree | 12ccd44a5ab58191d511b643484b32999dcedc27 /ext | |
parent | 0610f555ea4f3ba571482f90393fe8c0701cd58a (diff) | |
download | ruby-338eb0065bd81ba8ae8b9402abc94804a24594cc.tar.gz |
[ruby/strscan] StringScanner#captures: Return nil not "" for
unmached capture
(https://github.com/ruby/strscan/pull/72)
fix https://github.com/ruby/strscan/issues/70
If there is no substring matching the group (s[3]), the behavior is
different.
If there is no substring matching the group, the corresponding element
(s[3]) should be nil.
```
s = StringScanner.new('foobarbaz') #=> #<StringScanner 0/9 @ "fooba...">
s.scan /(foo)(bar)(BAZ)?/ #=> "foobar"
s[0] #=> "foobar"
s[1] #=> "foo"
s[2] #=> "bar"
s[3] #=> nil
s.captures #=> ["foo", "bar", ""]
s.captures.compact #=> ["foo", "bar", ""]
```
```
s = StringScanner.new('foobarbaz') #=> #<StringScanner 0/9 @ "fooba...">
s.scan /(foo)(bar)(BAZ)?/ #=> "foobar"
s[0] #=> "foobar"
s[1] #=> "foo"
s[2] #=> "bar"
s[3] #=> nil
s.captures #=> ["foo", "bar", nil]
s.captures.compact #=> ["foo", "bar"]
```
https://docs.ruby-lang.org/ja/latest/method/MatchData/i/captures.html
```
/(foo)(bar)(BAZ)?/ =~ "foobarbaz" #=> 0
$~.to_a #=> ["foobar", "foo", "bar", nil]
$~.captures #=> ["foo", "bar", nil]
$~.captures.compact #=> ["foo", "bar"]
```
* StringScanner#captures is not yet documented.
https://docs.ruby-lang.org/ja/latest/class/StringScanner.html
https://github.com/ruby/strscan/commit/1fbfdd3c6f
Diffstat (limited to 'ext')
-rw-r--r-- | ext/strscan/strscan.c | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/ext/strscan/strscan.c b/ext/strscan/strscan.c index a2bf56ce4f..7dbd971ae9 100644 --- a/ext/strscan/strscan.c +++ b/ext/strscan/strscan.c @@ -1243,10 +1243,10 @@ strscan_size(VALUE self) * If nothing was priorly matched, it returns nil. * * s = StringScanner.new("Fri Dec 12 1975 14:39") - * s.scan(/(\w+) (\w+) (\d+) /) # -> "Fri Dec 12 " - * s.captures # -> ["Fri", "Dec", "12"] - * s.scan(/(\w+) (\w+) (\d+) /) # -> nil - * s.captures # -> nil + * s.scan(/(\w+) (\w+) (\d+) (1980)?/) # -> "Fri Dec 12 " + * s.captures # -> ["Fri", "Dec", "12", nil] + * s.scan(/(\w+) (\w+) (\d+) (1980)?/) # -> nil + * s.captures # -> nil */ static VALUE strscan_captures(VALUE self) @@ -1262,9 +1262,13 @@ strscan_captures(VALUE self) new_ary = rb_ary_new2(num_regs); for (i = 1; i < num_regs; i++) { - VALUE str = extract_range(p, - adjust_register_position(p, p->regs.beg[i]), - adjust_register_position(p, p->regs.end[i])); + VALUE str; + if (p->regs.beg[i] == -1) + str = Qnil; + else + str = extract_range(p, + adjust_register_position(p, p->regs.beg[i]), + adjust_register_position(p, p->regs.end[i])); rb_ary_push(new_ary, str); } |