Add GitHub Actions workflow to test R builds

test/get_platforms.py

@@ -0,0 +1,31 @@
+import argparse
+import json
+import subprocess
+
+
+def main():
+    parser = argparse.ArgumentParser(description="Print R-builds platforms as JSON.")
+    parser.add_argument(
+        'platforms',
+        type=str,
+        nargs='?',
+        default='all',
+        help='Comma-separated list of platforms. Specify "all" to use all platforms (the default).'
+    )
+    args = parser.parse_args()
+    platforms = _get_platforms(which=args.platforms)
+    print(json.dumps(platforms))
+
+
+def _get_platforms(which='all'):
+    supported_platforms = subprocess.check_output(['make', 'print-platforms'], text=True)
+    supported_platforms = supported_platforms.split()
+    if which == 'all':
+        return supported_platforms
+    platforms = which.split(',')
+    platforms = [p for p in platforms if p in supported_platforms]
+    return platforms
+
+
+if __name__ == '__main__':
+    main()