Python: Copy Python extractor to codeql repo

python/extractor/tests/test_patterns.py

@@ -0,0 +1,27 @@
+import os
+import json
+import subprocess
+
+import semmle.path_filters
+from tests import test_utils
+
+class ExtractorPatternsTest(test_utils.ExtractorTest):
+
+    def __init__(self, name):
+        super(ExtractorPatternsTest, self).__init__(name)
+
+    def test(self):
+        repo_dir = subprocess.Popen(["git", "rev-parse", "--show-toplevel"], stdout=subprocess.PIPE).communicate()[0].rstrip().decode("utf-8")
+        test_file_path = os.path.abspath(os.path.join(repo_dir, "unit-tests", "files", "pattern-matching", "patterns.json"))
+        with open(test_file_path) as test_file:
+            test_patterns = json.load(test_file)
+        for test_pattern in test_patterns:
+            pattern = test_pattern["pattern"]
+            regex = semmle.path_filters.glob_to_regex(pattern)
+            for matching_path in test_pattern["should_match"]:
+                self.assertTrue(regex.match(matching_path), "Pattern \"%s\" did not match path \"%s\"." % (pattern, matching_path))
+            for matching_path in test_pattern["shouldnt_match"]:
+                self.assertFalse(regex.match(matching_path), "Pattern \"%s\" matched path \"%s\"." % (pattern, matching_path))
+
+    def test_escape_prefix(self):
+        semmle.path_filters.glob_to_regex("x", prefix="foo\\")