windows: Improve MSYS2-based CI builds.

Install the mingw variant of Python since it behaves more like a
'real' Windows CPython than the msys2 variant: os.name == 'nt',
not 'posix'.  Note that os.sep is still '/' though so we don't
actually need to skip the import_file test.
This way one single Python version can be used both for running
run-tests.py and getting the expected test output.

Signed-off-by: stijn <stijn@ignitron.net>

.github/workflows/ports_windows.yml

@@ -108,16 +108,6 @@ jobs:
       run:
         shell: msys2 {0}
     steps:
-    - name: Get Python path
-      id: python_path
-      shell: python
-      run: |
-        import os
-        import sys
-        output = f"python={os.fspath(sys.executable)}"
-        print(output)
-        with open(os.environ["GITHUB_OUTPUT"], "w") as f:
-            f.write(output)
     - uses: msys2/setup-msys2@v2
       with:
         msystem: ${{ matrix.sys }}
@@ -126,7 +116,7 @@ jobs:
           make
           mingw-w64-${{ matrix.env }}-gcc
           pkg-config
-          python3
+          mingw-w64-${{ matrix.env }}-python3
           git
           diffutils
     - uses: actions/checkout@v4
@@ -138,8 +128,7 @@ jobs:
       run: make -C ports/windows -j2 VARIANT=${{ matrix.variant }}
     - name: Run tests
       id: test
-      # msys python breaks tests so we need to use "real" windows python
-      run: MICROPY_CPYTHON3=$(cygpath "${{ steps.python_path.outputs.python }}") make -C ports/windows test_full VARIANT=${{ matrix.variant }}
+      run: make -C ports/windows test_full VARIANT=${{ matrix.variant }}
     - name: Print failures
       if: failure() && steps.test.conclusion == 'failure'
       working-directory: tests

ports/windows/Makefile

@@ -101,6 +101,9 @@ include $(TOP)/py/mkrules.mk
 
 .PHONY: test test_full
 
+# Note for recent gcc versions like 13.2:
+# - mingw64-x86_64 gcc builds will pass the math_domain_special test
+# - mingw64-ucrt64 gcc builds will pass all of the below tests
 RUN_TESTS_SKIP += -e math_fun -e float2int_double -e float_parse -e math_domain_special
 
 test: $(BUILD)/$(PROG) $(TOP)/tests/run-tests.py

ports/windows/README.md

@@ -45,7 +45,7 @@ Install MSYS2 from http://repo.msys2.org/distrib, start the msys2.exe shell and
 install the build tools:
 
     pacman -Syuu
-    pacman -S make mingw-w64-x86_64-gcc pkg-config python3
+    pacman -S make mingw-w64-x86_64-gcc pkg-config mingw-w64-x86_64-python3
 
 Start the mingw64.exe shell and build:
 

tests/run-tests.py

@@ -3,6 +3,7 @@
 import os
 import subprocess
 import sys
+import sysconfig
 import platform
 import argparse
 import inspect
@@ -583,10 +584,6 @@ def run_tests(pyb, tests, args, result_dir, num_threads=1):
             # fails with stack overflow on Debug builds
             skip_tests.add("misc/sys_settrace_features.py")
 
-            if os.getenv("MSYSTEM") is not None:
-                # fails due to wrong path separator
-                skip_tests.add("import/import_file.py")
-
     if upy_float_precision == 0:
         skip_tests.add("extmod/uctypes_le_float.py")
         skip_tests.add("extmod/uctypes_native_float.py")
@@ -699,7 +696,9 @@ def run_tests(pyb, tests, args, result_dir, num_threads=1):
 
     # Some tests use unsupported features on Windows
     if os.name == "nt":
-        skip_tests.add("import/import_file.py")  # works but CPython prints forward slashes
+        if not sysconfig.get_platform().startswith("mingw"):
+            # Works but CPython uses '\' path separator
+            skip_tests.add("import/import_file.py")
 
     # Some tests are known to fail with native emitter
     # Remove them from the below when they work