Fix: Be more strict when matching copyrights

Ensure that only matches containing at least a creation year and a
copyright holder are considered valid matches. This avoids treating
partial matches like `Copyright string xyz` in code as copyright
statements.

Author: wiegandm

pontos/updateheader/updateheader.py

@@ -90,14 +90,15 @@ def _find_copyright(
     """Match the line for the copyright_regex"""
     copyright_match = re.search(copyright_regex, line)
     if copyright_match:
-        return (
-            True,
-            CopyrightMatch(
-                creation_year=copyright_match.group(2),
-                modification_year=copyright_match.group(3),
-                company=copyright_match.group(4),
-            ),
-        )
+        if copyright_match.group(2) and copyright_match.group(4):
+            return (
+                True,
+                CopyrightMatch(
+                    creation_year=copyright_match.group(2),
+                    modification_year=copyright_match.group(3),
+                    company=copyright_match.group(4),
+                ),
+            )
     return False, None
 
 

tests/updateheader/test_header.py

@@ -73,6 +73,14 @@ def test_find_copyright(self):
             "# This program is free software: "
             "you can redistribute it and/or modify"
         )
+        not_a_copyright_line = """
+package product
+
+type FooProduct struct {
+	Version       string     `json:"version"`
+	SPDXLicenseID string     `json:"spdx-license-identifier"`
+	Copyright     string     `json:"copyright"`
+"""  # noqa: E501
 
         # Full match
         found, match = find_copyright(
@@ -101,6 +109,13 @@ def test_find_copyright(self):
         self.assertFalse(found)
         self.assertIsNone(match)
 
+        # Looks like a copyright, but isn't
+        found, match = find_copyright(
+            copyright_regex=self.regex, line=not_a_copyright_line
+        )
+        self.assertFalse(found)
+        self.assertIsNone(match)
+
     def test_find_spdx_copyright(self):
         test_line = "# SPDX-FileCopyrightText: 1995-2021 Greenbone AG"
         test2_line = "# SPDX-FileCopyrightText: 1995 Greenbone AG"