Re: [PATCH] Avoid broken Solaris tr
- From
Ben Walton <bdwalton@gmail.com>
- Date
- Oct 28, 2013, 09:02 UTC
- Message-ID
- <CAP30j17OCrYjsVK+W_TR-g99YmzY3d9TnYfwHXK7+6vPrVjDaQ@mail.gmail.com>
- In-Reply-To
- <7vli672gql.fsf@alter.siamese.dyndns.org>
On Tue, Jun 18, 2013 at 11:31 PM, Junio C Hamano <gitster@pobox.com> wrote:
Sorry for the very slow reply. This got lost in my inbox and I forgot about it.
Show 9 quoted lines
> Ben Walton <bdwalton@gmail.com> writes: > >> Solaris' tr (both /usr/bin/ and /usr/xpg4/bin) fail to handle the case >> where the first argument is a multi-character set and the second is a >> single null character. > > Almost all the tr invocations look like converting LF to NUL, except > for two that squash a colon ':', HT and LF all to NUL. Is Solaris's > tr fine with the former but not the latter?
In retrospect, this isn't brokenness, just a difference in System V vs BSD semantics for tr, both of which are allowed by POSIX since the behaviour in question is specifically unspecified by the standard. The System V behaviour is to require a 1:1 map between string1 and string2 transformations whereas BSD behaviour (when len(string2) < len(string1)) is to pad string2 with the last character in string2 until the lengths are equal.
Show 34 quoted lines
>
>> We make this change globally in t0008-ignores instead of just for the
>> cases where it matters in order to maintain consistency.
>
> I am not suggesting to keep 'tr "\n" "\0"', but just wanted to make
> sure I am reading the first paragraph correctly. If we are
> rewriting, we should do so consistently.
>
>> +perl -pne 's/^"//; s/\\//; s/"$//; s/\n/\0/g' stdin >stdin0
>
> What is -pne? Is it the same as -pe?
>
> tr/\n/\0/ (or y/\n/\0/) may be more faithful to the original.
>
>
>> +perl -pne 's/^"//; s/\\//; s/"$//; s/\n/\0/g' expected-default > \
>> + expected-default0
>
> Ditto. We may want to give the same script used in the above two
> (and twice again in the later hunk) more descriptive name, e.g.
>
> broken_c_unquote () {
> perl -pe '... that script ...' "$@"
> }
>
> broken_c_quote stdin >stdin0
>
> Side note: the script is broken as a generic C-unquote function in
> multiple ways. It does not work if it has more than one backslash
> quoted characters, it does not understand \t, \b, \015, \\, etc. to
> name two.
>
> But the breakage does not matter for the strings used in the test
> vector.I've updated the patch and will forward it shortly.
Thanks -Ben -- --------------------------------------------------------------------------------------------------------------------------- Take the risk of thinking for yourself. Much more happiness, truth, beauty and wisdom will come to you that way.
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