Backport PR #18233 on branch v3.3.x (Fix cibuildwheel trigger condition.)

.github/workflows/cibuildwheel.yml

@@ -1,6 +1,12 @@
 name: Build CI wheels
 
-on: [push, tags]
+on:
+  push:
+    branches:
+      - master
+      - v[0-9]+.[0-9]+.x
+    tags:
+      - v*
 
 jobs:
   build_wheels:
@@ -12,6 +18,8 @@ jobs:
 
     steps:
       - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
 
       - uses: actions/setup-python@v2
         name: Install Python
@@ -22,17 +30,40 @@ jobs:
         run: |
           python -m pip install cibuildwheel==1.5.5
 
-      - name: Build wheels
+      - name: Build wheels for CPython
         run: |
-          python -m cibuildwheel --output-dir wheelhouse
+          python -m cibuildwheel --output-dir dist
         env:
           CIBW_BUILD: "cp3?-*"
           CIBW_SKIP: "cp35-* cp36-*"
           CIBW_MANYLINUX_X86_64_IMAGE: manylinux1
           CIBW_MANYLINUX_I686_IMAGE: manylinux1
-          CIBW_MANYLINUX_PYPY_X86_64_IMAGE: manylinux1
+          CIBW_BEFORE_BUILD: pip install numpy==1.15
+
+      - name: Build wheels for CPython 3.6
+        run: |
+          python -m cibuildwheel --output-dir dist
+        env:
+          CIBW_BUILD: "cp36-*"
+          CIBW_MANYLINUX_X86_64_IMAGE: manylinux1
+          CIBW_MANYLINUX_I686_IMAGE: manylinux1
+          CIBW_BEFORE_BUILD: pip install numpy==1.15
+        if: >
+          startsWith(github.ref, 'refs/heads/v3.3') ||
+          startsWith(github.ref, 'refs/tags/v3.3')
+
+      - name: Build wheels for PyPy
+        run: |
+          python -m cibuildwheel --output-dir dist
+        env:
+          CIBW_BUILD: "pp3?-*"
+          CIBW_BEFORE_BUILD: pip install numpy==1.15
+        if: >
+          runner.os != 'Windows' && (
+          startsWith(github.ref, 'refs/heads/v3.3') ||
+          startsWith(github.ref, 'refs/tags/v3.3') )
 
       - uses: actions/upload-artifact@v2
         with:
           name: wheels
-          path: ./wheelhouse/*.whl
+          path: ./dist/*.whl