Re: [PATCH 4/5] gdb/testsuite: change newline patterns used in gdb_test

[Andrew Burgess <aburgess@redhat.com>]

Simon Marchi <simark@simark.ca> writes:

> On 3/31/23 16:20, Andrew Burgess via Gdb-patches wrote:
>> This commit makes two changes to how we match newline characters in
>> the gdb_test proc.
>> 
>> First, for the newline pattern between the command output and the
>> prompt, I propose changing from '[\r\n]+' to an explicit '\r\n'.
>> 
>> The old pattern would spot multiple newlines, and so there are a few
>> places where, as part of this commit, I've needed to add an extra
>> trailing '\r\n' to the pattern in the main test file, where GDB's
>> output actually includes a blank line.
>> 
>> But I think this is a good thing.  If a command produces a blank line
>> then we should be checking for it, the current test doesn't.
>> 
>> Additionally, the existing pattern will happily match a partial
>> newline.  There are a strangely large number of tests that end with a
>> random '.' character.  Not matching a literal period, but matching any
>> single character, this is then matching half of the trailing newline
>> sequence, while the \[\r\n\]+ in gdb_test is matching the other half
>> of the sequence.  I can think of no reason why this would be
>> intentional.  All of these are cleaned up after this commit.
>> 
>> The basic rule of gdb_test after this is that the expected pattern
>> needs to match everything up to, but not including the newline
>> sequence immediately before the GDB prompt.
>> 
>> Second, while I was cleaning up newline matching in gdb_test, I've
>> also removed the '[\r\n]*' that was added to the start of the pattern
>> passed to gdb_test_multiple.
>> 
>> The addition of this pattern adds no value.  If the user pattern
>> matches at the start of a line then this would match against the
>> newline sequence.  But, due to the '*', if the user pattern doesn't
>> match at the start of a line then this group doesn't care, it'll
>> happily match nothing.
>> 
>> As such, there's no value to it, it just adds more complexity for no
>> gain, so I'm removing it.  No tests will need updating as a
>> consequence of this part of the patch.
>
> Hi Andrew,
>
> Starting with this patch, I see many new failures in gdb.trace (using
> one of the gdbserver boards), for instance the first one being:
>
>   FAIL: gdb.trace/collection.exp: collect args collectively: collected arg char

Sorry for that.

I thought I'd run the gdbserver tests, but I guess not.

I have a fix for gdb.trace/collection.exp, I'm just running the full set
of tests to see if there are any other regressions I missed.

I'll push the fix(es) soon.

Thanks,
Andrew