1 files changed, 87 insertions, 0 deletions
diff --git a/tools/lint/python/check_compat.py b/tools/lint/python/check_compat.py
new file mode 100755
index 0000000000..25a15fcedc
--- /dev/null
+++ b/tools/lint/python/check_compat.py
@@ -0,0 +1,87 @@
+#!/usr/bin/env python
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import ast
+import json
+import sys
+
+
+def parse_file(f):
+    with open(f, "rb") as fh:
+        content = fh.read()
+    try:
+        return ast.parse(content)
+    except SyntaxError as e:
+        err = {
+            "path": f,
+            "message": e.msg,
+            "lineno": e.lineno,
+            "column": e.offset,
+            "source": e.text,
+            "rule": "is-parseable",
+        }
+        print(json.dumps(err))
+
+
+def check_compat_py2(f):
+    """Check Python 2 and Python 3 compatibility for a file with Python 2"""
+    root = parse_file(f)
+
+    # Ignore empty or un-parseable files.
+    if not root or not root.body:
+        return
+
+    futures = set()
+    haveprint = False
+    future_lineno = 1
+    may_have_relative_imports = False
+    for node in ast.walk(root):
+        if isinstance(node, ast.ImportFrom):
+            if node.module == "__future__":
+                future_lineno = node.lineno
+                futures |= set(n.name for n in node.names)
+            else:
+                may_have_relative_imports = True
+        elif isinstance(node, ast.Import):
+            may_have_relative_imports = True
+        elif isinstance(node, ast.Print):
+            haveprint = True
+
+    err = {
+        "path": f,
+        "lineno": future_lineno,
+        "column": 1,
+    }
+
+    if "absolute_import" not in futures and may_have_relative_imports:
+        err["rule"] = "require absolute_import"
+        err["message"] = "Missing from __future__ import absolute_import"
+        print(json.dumps(err))
+
+    if haveprint and "print_function" not in futures:
+        err["rule"] = "require print_function"
+        err["message"] = "Missing from __future__ import print_function"
+        print(json.dumps(err))
+
+
+def check_compat_py3(f):
+    """Check Python 3 compatibility of a file with Python 3."""
+    parse_file(f)
+
+
+if __name__ == "__main__":
+    if sys.version_info[0] == 2:
+        fn = check_compat_py2
+    else:
+        fn = check_compat_py3
+
+    manifest = sys.argv[1]
+    with open(manifest, "r") as fh:
+        files = fh.read().splitlines()
+
+    for f in files:
+        fn(f)
+
+    sys.exit(0)