ci: build and test rez with and without mypyc

Add a 'mypyc' axis to the installation and tests workflows so CI exercises
both the pure-python build (REZ_MYPYC=0) and the mypyc-compiled build
(REZ_MYPYC=1) across the full OS x Python matrix. fail-fast is off, so each
configuration reports independently and we can see exactly which ones the
compiled build supports.

Point the pyproject build requirement at our mypy fork
(github.com/chadrik/mypy@rez-mypyc-fixes), which carries the fixes needed to
compile rez. This makes an isolated build (pip install ., install.py, ...)
automatically pick up the right mypy when building with mypyc, with no extra
CI steps. Verified end to end: an isolated REZ_MYPYC=1 build pulls the fork
and produces the compiled extensions.

Author: chadrik

.github/workflows/installation.yaml

@@ -27,14 +27,15 @@ permissions:
 
 jobs:
   main:
-    name: ${{ matrix.os }} - ${{ matrix.python-version }} - ${{ matrix.method }}
+    name: ${{ matrix.os }} - ${{ matrix.python-version }} - ${{ matrix.method }} - mypyc=${{ matrix.mypyc }}
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
         os: ['ubuntu-latest', 'macos-latest', 'windows-latest']
         python-version: ['3.8', '3.9', '3.10', '3.11', '3.12', '3.13']
         method: ['install' ,'pip']
+        mypyc: [false, true]
 
         include:
         # ubuntu
@@ -76,6 +77,7 @@ jobs:
     - name: Install
       env:
         MATRIX_PYTHON_VERSION: ${{ matrix.python-version }}
+        REZ_MYPYC: ${{ matrix.mypyc && '1' || '0' }}
       run: |
         ${{ matrix.REZ_INSTALL_COMMAND }}
 

.github/workflows/tests.yaml

@@ -39,6 +39,8 @@ jobs:
       matrix:
         os: ['macos-latest', 'ubuntu-latest', 'windows-latest']
         python-version: ['3.8', '3.9', '3.10', '3.11', '3.12', '3.13']
+        mypyc: [false, true]
+
         include:
         - os: macos-latest
           shells: 'sh,csh,bash,tcsh,zsh,pwsh'
@@ -73,6 +75,8 @@ jobs:
         sudo apt-get install -y csh tcsh zsh
 
     - name: Install rez
+      env:
+        REZ_MYPYC: ${{ matrix.mypyc && '1' || '0' }}
       run: python ./install.py ./installdir
 
     - name: Install test system dependencies (macOS)

pyproject.toml

@@ -1,5 +1,9 @@
 [build-system]
-requires = ["setuptools", "mypy[mypyc]"]
+# Building rez with mypyc (the default; set REZ_MYPYC=0 to build pure-python)
+# requires our fork of mypy, which carries fixes needed to compile rez. Those
+# fixes are pending upstreaming; until they land, pin the fork so that an
+# isolated build (pip install ., install.py, etc.) picks up the right mypy.
+requires = ["setuptools", "mypy[mypyc] @ git+https://github.com/chadrik/mypy@rez-mypyc-fixes"]
 build-backend = "setuptools.build_meta"
 
 [tool.mypy]