👷 Test across platforms all supported platforms

Author: TeoZosa

.github/workflows/ci.yml

@@ -116,15 +116,18 @@ jobs:
   # Tests jobs ------------------------
 
   test:
-    name: Python ${{ matrix.python-version }}
-    runs-on: "ubuntu-latest"
-    env:
-      USING_COVERAGE: "3.9"
-
     strategy:
       matrix:
+        os: ["ubuntu-latest", "windows-latest", "macos-latest"]
         python-version: ["3.7", "3.8", "3.9"]
 
+    name: Python ${{ matrix.python-version }} (${{ matrix.os }})
+    runs-on: ${{ matrix.os }}
+
+    env:
+      USING_COVERAGE_PY_VER: "3.9"
+      USING_COVERAGE_OS: "3.9"
+
     steps:
       - name: Check out the repository
         uses: actions/[email protected]
@@ -155,7 +158,8 @@ jobs:
           make test
 
       - name: Upload coverage to Codecov
-        if: "contains(env.USING_COVERAGE, matrix.python-version)"
+        if: "contains(matrix.python-version, env.USING_COVERAGE_PY_VER) &&
+             contains(matrix.python-os, env.USING_COVERAGE_OS)"
         uses: "codecov/[email protected]"
         with:
           file: ./.tox/coverage.xml