7.0.0 _glob_to_regex fails in directories with regexp characters

[ktlim]

Describe the bug
We build and test in directories that contain the + character (as a separator in a version string). Using a .coveragerc file in such a directory that contains an omit specification that does not begin with a * or ? wildcard fails.

To Reproduce
How can we reproduce the problem? Please be specific. Don't link to a failing CI job. Answer the questions below:

1. What version of Python are you using?
   3.10
2. What version of coverage.py shows the problem? The output of coverage debug sys is helpful.
   7.0.0. 6.5.0 is fine.

-- sys -------------------------------------------------------
               coverage_version: 7.0.0
                coverage_module: /sdf/home/k/ktl/.conda/envs/covtest/lib/python3.10/site-packages/coverage/__init__.py
                         tracer: -none-
                        CTracer: available
           plugins.file_tracers: -none-
            plugins.configurers: -none-
      plugins.context_switchers: -none-
              configs_attempted: .coveragerc
                                 setup.cfg
                                 tox.ini
                                 pyproject.toml
                   configs_read: -none-
                    config_file: None
                config_contents: -none-
                      data_file: -none-
                         python: 3.10.8 | packaged by conda-forge | (main, Nov 22 2022, 08:23:14) [GCC 10.4.0]
                       platform: Linux-4.18.0-372.32.1.el8_6.x86_64-x86_64-with-glibc2.28
                 implementation: CPython
                     executable: /sdf/home/k/ktl/.conda/envs/covtest/bin/python
                   def_encoding: utf-8
                    fs_encoding: utf-8
                            pid: 2829394
                            cwd: /sdf/home/k/ktl
                           path: /sdf/home/k/ktl/.conda/envs/covtest/bin
                                 /sdf/home/k/ktl/.conda/envs/covtest/eups/python
                                 /sdf/home/k/ktl/.conda/envs/covtest/lib/python310.zip
                                 /sdf/home/k/ktl/.conda/envs/covtest/lib/python3.10
                                 /sdf/home/k/ktl/.conda/envs/covtest/lib/python3.10/lib-dynload
                                 /sdf/home/k/ktl/.conda/envs/covtest/lib/python3.10/site-packages
                    environment: CONDA_PYTHONBREAKPOINT =
                                 CONDA_PYTHON_EXE = /sdf/group/rubin/sw/conda/bin/python
                                 HOME = /sdf/home/k/ktl
                                 OBJCOPY = /sdf/home/k/ktl/.conda/envs/covtest/bin/x86_64-conda-linux-gnu-objcopy
                                 PYTHONPATH = /sdf/home/k/ktl/.conda/envs/covtest/eups/python
                                 _CONDA_PYTHON_SYSCONFIGDATA_NAME = _sysconfigdata_x86_64_conda_cos6_linux_gnu
                   command_line: /sdf/home/k/ktl/.conda/envs/covtest/bin/coverage debug sys
         sqlite3_sqlite_version: 3.40.0
             sqlite3_temp_store: 0
        sqlite3_compile_options: ATOMIC_INTRINSICS=1, COMPILER=gcc-10.4.0, DEFAULT_AUTOVACUUM,
                                 DEFAULT_CACHE_SIZE=-2000, DEFAULT_FILE_FORMAT=4,
                                 DEFAULT_JOURNAL_SIZE_LIMIT=-1, DEFAULT_MMAP_SIZE=0, DEFAULT_PAGE_SIZE=4096,
                                 DEFAULT_PCACHE_INITSZ=20, DEFAULT_RECURSIVE_TRIGGERS,
                                 DEFAULT_SECTOR_SIZE=4096, DEFAULT_SYNCHRONOUS=2,
                                 DEFAULT_WAL_AUTOCHECKPOINT=1000, DEFAULT_WAL_SYNCHRONOUS=2,
                                 DEFAULT_WORKER_THREADS=0, ENABLE_COLUMN_METADATA, ENABLE_DBSTAT_VTAB,
                                 ENABLE_FTS3, ENABLE_FTS3_TOKENIZER, ENABLE_FTS4, ENABLE_FTS5,
                                 ENABLE_GEOPOLY, ENABLE_MATH_FUNCTIONS, ENABLE_RTREE, ENABLE_UNLOCK_NOTIFY,
                                 MALLOC_SOFT_LIMIT=1024, MAX_ATTACHED=10, MAX_COLUMN=2000,
                                 MAX_COMPOUND_SELECT=500, MAX_DEFAULT_PAGE_SIZE=8192, MAX_EXPR_DEPTH=10000,
                                 MAX_FUNCTION_ARG=127, MAX_LENGTH=1000000000, MAX_LIKE_PATTERN_LENGTH=50000,
                                 MAX_MMAP_SIZE=0x7fff0000, MAX_PAGE_COUNT=1073741823, MAX_PAGE_SIZE=65536,
                                 MAX_SQL_LENGTH=1000000000, MAX_TRIGGER_DEPTH=1000,
                                 MAX_VARIABLE_NUMBER=250000, MAX_VDBE_OP=250000000, MAX_WORKER_THREADS=8,
                                 MUTEX_PTHREADS, SECURE_DELETE, SYSTEM_MALLOC, TEMP_STORE=1, THREADSAFE=1

1. What versions of what packages do you have installed? The output of pip freeze is helpful.

(covtest) $ conda list
# packages in environment at /sdf/home/k/ktl/.conda/envs/covtest:
#
# Name                    Version                   Build  Channel
_libgcc_mutex             0.1                 conda_forge    conda-forge
_openmp_mutex             4.5                       2_gnu    conda-forge
bzip2                     1.0.8                h7f98852_4    conda-forge
ca-certificates           2022.12.7            ha878542_0    conda-forge
coverage                  7.0.0           py311h2582759_0    conda-forge
ld_impl_linux-64          2.39                 hcc3a1bd_1    conda-forge
libffi                    3.4.2                h7f98852_5    conda-forge
libgcc-ng                 12.2.0              h65d4601_19    conda-forge
libgomp                   12.2.0              h65d4601_19    conda-forge
libnsl                    2.0.0                h7f98852_0    conda-forge
libsqlite                 3.40.0               h753d276_0    conda-forge
libuuid                   2.32.1            h7f98852_1000    conda-forge
libzlib                   1.2.13               h166bdaf_4    conda-forge
ncurses                   6.3                  h27087fc_1    conda-forge
openssl                   3.0.7                h0b41bf4_1    conda-forge
pip                       22.3.1             pyhd8ed1ab_0    conda-forge
python                    3.11.0          ha86cf86_0_cpython    conda-forge
python_abi                3.11                    3_cp311    conda-forge
readline                  8.1.2                h0f457ee_0    conda-forge
setuptools                65.6.3             pyhd8ed1ab_0    conda-forge
tk                        8.6.12               h27826a3_0    conda-forge
tomli                     2.0.1              pyhd8ed1ab_0    conda-forge
tzdata                    2022g                h191b570_0    conda-forge
wheel                     0.38.4             pyhd8ed1ab_0    conda-forge
xz                        5.2.6                h166bdaf_0    conda-forge

1. What code shows the problem? Give us a specific commit of a specific repo that we can check out. If you've already worked around the problem, please provide a commit before that fix.

$ mkdir cov+test cov+test/tests
$ cd cov+test
$ echo -e "[run]\nomit = x/*" > .coveragerc
$ echo -e "def test_foo():\n    assert 4 == 4" > tests/test_foo.py
$ coverage run tests/test_foo.py
File pattern can't include '+'
$ cd ..
$ mv cov+test covtest
$ cd covtest
$ coverage run tests/test_foo.py
$

1. What commands did you run?
   See above.

Expected behavior
See above.

Additional context
I'm not sure why a complex custom glob-to-regexp translator was used instead of glob, but I suggest that regexp metacharacters be quoted instead of causing failures, as they're quite legal and not infrequently used in pathnames. Perhaps leaving out files.py:328 would be sufficient.

[nedbat]

This is now fixed in commit 152cdc7. Plus signs and curly braces are no longer forbidden in directory and file names.

[nedbat]

This is now released as part of coverage 7.0.1.