Add comparison script

tests/syntax-tests/compare_highlighted_versions.py

@@ -0,0 +1,65 @@
+#!/usr/bin/env python3
+
+import glob
+import sys
+import os.path as path
+import difflib
+import argparse
+
+
+def compare_highlighted_versions(root_old, root_new):
+    print("Comparing the following directories:")
+    print(" -", root_old)
+    print(" -", root_new)
+    has_changes = False
+    for path_old in glob.glob(path.join(root_old, "*", "*")):
+        filename = path.basename(path_old)
+        dirname = path.basename(path.dirname(path_old))
+
+        path_new = path.join(root_new, dirname, filename)
+
+        print("\n========== {}/{}".format(dirname, filename))
+
+        with open(path_old) as file_old:
+            lines_old = file_old.readlines()
+
+        with open(path_new) as file_new:
+            lines_new = file_new.readlines()
+
+        diff = difflib.unified_diff(
+            lines_old, lines_new, fromfile=path_old, tofile=path_new
+        )
+
+        file_has_changes = False
+        for line in diff:
+            print(line, end="")
+            file_has_changes = True
+
+        if file_has_changes:
+            has_changes = True
+        else:
+            print("No changes")
+    print()
+
+    return has_changes
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(
+        description="This script compares two directories that were created "
+        "by 'create_highlighted_versions.py'."
+    )
+    parser.add_argument(
+        "OLD", help="Path to the old (stored) version of the highlighted output",
+    )
+    parser.add_argument(
+        "NEW", help="Path to the new version of the highlighted output",
+    )
+
+    args = parser.parse_args()
+
+    if compare_highlighted_versions(args.OLD, args.NEW):
+        print("Error: files with changes have been found")
+        sys.exit(1)
+    else:
+        print("Directories are the same")