Only test the files impacted by changes in the diff (#12644)

* Base test

* More test

* Fix mistake

* Add a docstring change

* Add doc ignore

* Add changes

* Add recursive dep search

* Add recursive dep search

* save

* Finalize test mapping

* Fix bug

* Print prettier

* Ignore comments and empty lines

* Make script runnable from anywhere

* Need dev install

* Like that

* Adapt

* Add as artifact

* Try on torch tests

* Fix yaml error

* Install GitPython

* Apply everywhere

* Be more defensive

* Revert to all tests if something is wrong

* Install GitPython

* Test if there are tests before launching.

* Fixes

* Fixes

* Fixes

* Fixes

* Bash syntax is horrible

* Be less stupid

* Try differently

* Typo

* Typo

* Typo

* Style

* Better name

* Escape quotes

* Ignore black unhelpful re-formatting

* Not a docstring

* Deal with inits in dependency map

* Run all tests once PR is merged.

* Add last job

* Apply suggestions from code review

Co-authored-by: Stas Bekman <stas00@users.noreply.github.com>

* Stronger dependencies gather

* Ignore empty lines too!

* Clean up

* Fix quality

Co-authored-by: Stas Bekman <stas00@users.noreply.github.com>

tests/conftest.py

@@ -53,3 +53,9 @@ def pytest_terminal_summary(terminalreporter):
     make_reports = terminalreporter.config.getoption("--make-reports")
     if make_reports:
         pytest_terminal_summary_main(terminalreporter, id=make_reports)
+
+
+def pytest_sessionfinish(session, exitstatus):
+    # If no tests are collected, pytest exists with code 5, which makes the CI fail.
+    if exitstatus == 5:
+        session.exitstatus = 0