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Problem: regex: wrong match when searching multi-byte char
case-insensitive (diffsetter)
Solution: Apply proper case-folding for characters and search-string
This patch does the following 4 things:
1) When the regexp engine compares two utf-8 codepoints case
insensitive it may match an adjacent character, because it assumes
it can step over as many bytes as the pattern contains.
This however is not necessarily true because of case-folding, a
multi-byte UTF-8 character can be considered equal to some
single-byte value.
Let's consider the pattern 'ſ' and the string 's'. When comparing and
ignoring case, the single character 's' matches, and since it matches
Vim will try to step over the match (by the amount of bytes of the
pattern), assuming that since it matches, the length of both strings is
the same.
However in that case, it should only step over the single byte value
's' by 1 byte and try to start matching after it again. So for the
backtracking engine we need to ensure:
* we try to match the correct length for the pattern and the text
* in case of a match, we step over it correctly
There is one tricky thing for the backtracing engine. We also need to
calculate correctly the number of bytes to compare the 2 different
utf-8 strings s1 and s2. So we will count the number of characters in
s1 that the byte len specified. Then we count the number of bytes to
step over the same number of characters in string s2 and then we can
correctly compare the 2 utf-8 strings.
2) A similar thing can happen for the NFA engine, when skipping to the
next character to test for a match. We are skipping over the regstart
pointer, however we do not consider the case that because of
case-folding we may need to adjust the number of bytes to skip over.
So this needs to be adjusted in find_match_text() as well.
3) A related issue turned out, when prog->match_text is actually empty.
In that case we should try to find the next match and skip this
condition.
4) When comparing characters using collections, we must also apply case
folding to each character in the collection and not just to the
current character from the search string. This doesn't apply to the
NFA engine, because internally it converts collections to branches
[abc] -> a\|b\|c
fixes: vim/vim#14294
closes: vim/vim#14756
22e8e12d9f
N/A patches:
vim-patch:9.0.1771: regex: combining chars in collections not handled
vim-patch:9.0.1777: patch 9.0.1771 causes problems
Co-authored-by: Christian Brabandt <cb@256bit.org>
This directory contains tests for various Vim features.
For testing an indent script see runtime/indent/testdir/README.txt.
If it makes sense, add a new test method to an already existing file. You may
want to separate it from other tests with comment lines.
TO ADD A NEW STYLE TEST:
1) Create a test_<subject>.vim file.
2) Add test_<subject>.res to NEW_TESTS_RES in Make_all.mak in alphabetical
order.
3) Also add an entry "test_<subject>" to NEW_TESTS in Make_all.mak.
4) Use make test_<subject> to run a single test.
At 2), instead of running the test separately, it can be included in
"test_alot". Do this for quick tests without side effects. The test runs a
bit faster, because Vim doesn't have to be started, one Vim instance runs many
tests.
At 4), to run a test in GUI, add "GUI_FLAG=-g" to the make command.
What you can use (see test_assert.vim for an example):
- Call assert_equal(), assert_true(), assert_false(), etc.
- Use assert_fails() to check for expected errors.
- Use try/catch to avoid an exception aborts the test.
- Use test_alloc_fail() to have memory allocation fail. This makes it possible
to check memory allocation failures are handled gracefully. You need to
change the source code to add an ID to the allocation. Add a new one to
alloc_id_T, before aid_last.
- Use test_override() to make Vim behave differently, e.g. if char_avail()
must return FALSE for a while. E.g. to trigger the CursorMovedI autocommand
event. See test_cursor_func.vim for an example.
- If the bug that is being tested isn't fixed yet, you can throw an exception
with "Skipped" so that it's clear this still needs work. E.g.: throw
"Skipped: Bug with <c-e> and popupmenu not fixed yet"
- The following environment variables are recognized and can be set to
influence the behavior of the test suite (see runtest.vim for details)
- $TEST_MAY_FAIL=Test_channel_one - ignore those failing tests
- $TEST_FILTER=Test_channel - only run test that match this pattern
- $TEST_SKIP_PAT=Test_channel - skip tests that match this pattern
- $TEST_NO_RETRY=yes - do not try to re-run failing tests
You can also set them in Vim:
:let $TEST_MAY_FAIL = 'Test_channel_one'
:let $TEST_FILTER = '_set_mode'
:let $TEST_SKIP_PAT = 'Test_loop_forever'
:let $TEST_NO_RETRY = 'yes'
Use an empty string to revert, e.g.:
:let $TEST_FILTER = ''
- See the start of runtest.vim for more help.
TO ADD A SCREEN DUMP TEST:
Mostly the same as writing a new style test. Additionally, see help on
"terminal-dumptest". Put the reference dump in "dumps/Test_func_name.dump".
OLD STYLE TESTS:
There are a few tests that are used when Vim was built without the +eval
feature. These cannot use the "assert" functions, therefore they consist of a
.in file that contains Normal mode commands between STARTTEST and ENDTEST.
They modify the file and the result gets written in the test.out file. This
is then compared with the .ok file. If they are equal the test passed. If
they differ the test failed.
RUNNING THE TESTS:
To run a single test from the src directory:
$ make test_<name>
The below commands should be run from the src/testdir directory.
To run a single test:
$ make test_<name>.res
The file 'messages' contains the messages generated by the test script. If a
test fails, then the test.log file contains the error messages. If all the
tests are successful, then this file will be an empty file.
- To run a single test function from a test script:
$ ../vim -u NONE -S runtest.vim <test_file>.vim <function_name>
- To execute only specific test functions, add a second argument:
$ ../vim -u NONE -S runtest.vim test_channel.vim open_delay
- To run all the tests:
$ make
- To run the test on MS-Windows using the MSVC nmake:
> nmake -f Make_dos.mak
- To run the tests with GUI Vim:
$ make GUI_FLAG=-g
or
$ make VIMPROG=../gvim
- To cleanup the temporary files after running the tests:
$ make clean