51ca2354d0
Substitutions can be added in a couple different ways; they can be added via the calling python scripts by adding entries to the config.substitutions dictionary, or via DEFINE lines in the scripts themselves. The substitution strings passed to Python's re classes are interpreted so that backslashes expand to escape sequences, and literal backslashes need to be escaped. On Unix, the script defined substitutions don't (usually, so far) contain backslashes - but on Windows, they often do, due to paths containing backslashes. This lead to a Windows specific escaping of backslashes before doing Python re substitutions - since 7c9eab8fef0ed79a5911d21eb97b6b0fa9d39f82. There's nothing inherently Windows specific about this though - any intended literal backslashes in the substitution strings need to be escaped; this is how the Python re API works. The DEFINE lines were added later, and in order to cope with backslashes, escaping of backslashes was added in the SubstDirective class in TestRunner, applying to DEFINE lines in the tests only. The fact that the escaping right before passing to the Python re API was done conditionally on Windows led to two inconsistencies: - DEFINE lines in the tests that contain backslashes got double backslashes on Windows. (This was visible as a FIXME in llvm/utils/lit/tests/Inputs/shtest-define/value-escaped.txt.) - Script provided substitutions containing backslashes did not work on Unix, but they did work on Windows. By removing the escaping from SubstDirective and escaping it unconditionally in the processLine function, before feeding the substitutions to Python's re classes, we should have consistent behaviour across platforms, and get rid of the FIXME in the lit test. This fixes issues with substitutions containing backslashes on Unix platforms, as encountered in PR #86649.
===============================
lit - A Software Testing Tool
===============================
About
=====
*lit* is a portable tool for executing LLVM and Clang style test suites,
summarizing their results, and providing indication of failures. *lit* is
designed to be a lightweight testing tool with as simple a user interface as
possible.
Features
========
* Portable!
* Flexible test discovery.
* Parallel test execution.
* Support for multiple test formats and test suite designs.
Documentation
=============
The official *lit* documentation is in the man page, available online at the LLVM
Command Guide: http://llvm.org/cmds/lit.html.
Source
======
The *lit* source is available as part of LLVM, in the LLVM source repository:
https://github.com/llvm/llvm-project/tree/main/llvm/utils/lit
Contributing to lit
===================
Please browse the issues labeled *tools:llvm-lit* in LLVM's issue tracker for
ideas on what to work on:
https://github.com/llvm/llvm-project/labels/tools%3Allvm-lit
Before submitting patches, run the test suite to ensure nothing has regressed::
# From within your LLVM source directory.
utils/lit/lit.py \
--path /path/to/your/llvm/build/bin \
utils/lit/tests
Note that lit's tests depend on ``not`` and ``FileCheck``, LLVM utilities.
You will need to have built LLVM tools in order to run lit's test suite
successfully.
You'll also want to confirm that lit continues to work when testing LLVM.
Follow the instructions in http://llvm.org/docs/TestingGuide.html to run the
regression test suite:
make check-llvm
And be sure to run the llvm-lit wrapper script as well:
/path/to/your/llvm/build/bin/llvm-lit utils/lit/tests
Finally, make sure lit works when installed via setuptools:
python utils/lit/setup.py install
lit --path /path/to/your/llvm/build/bin utils/lit/tests