[cr checker]: fix copyright detection for year ranges

Author: hoe-jo

cr_checker/tests/test_cr_checker.py

@@ -443,3 +443,19 @@ def test_process_files_detects_duplicate_header(tmp_path):
 
     assert results["duplicate_copyright"] == 1
     assert results["no_copyright"] == 0
+
+
+# test that has_duplicate_copyright detects two headers with different year ranges
+def test_has_duplicate_copyright_detects_different_year_ranges(tmp_path):
+    cr_checker = load_cr_checker_module()
+    test_file = tmp_path / "file.py"
+    header_template = load_template("py")
+    header1 = header_template.format(year="2026", author="Author")
+    header2 = header_template.format(year="2024-2026", author="Author")
+    test_file.write_text(header1 + header2 + "some content\n", encoding="utf-8")
+
+    result = cr_checker.has_duplicate_copyright(
+        test_file, header_template, False, "utf-8", 0
+    )
+
+    assert result is True

cr_checker/tool/cr_checker.py

@@ -396,7 +396,7 @@ def has_copyright(path, template, use_mmap, encoding, offset, config=None):
         if BORDER_FILL_PATTERN.search(stripped_line):
             regex_parts.append(line_to_flexible_regex(line))
         else:
-            formatted = line.format(year=r"\\d\{4\}", author=r"\.\*")
+            formatted = line.format(year=r"\\d\{4\}\(-\\d\{4\}\)\?", author=r"\.\*")
             regex_parts.append(convert_bre_to_regex(formatted))
     template_regex = "".join(regex_parts) + "\n?"
 
@@ -431,7 +431,7 @@ def has_duplicate_copyright(path, template, use_mmap, encoding, offset):
         if BORDER_FILL_PATTERN.search(stripped_line):
             regex_parts.append(line_to_flexible_regex(line))
         else:
-            formatted = line.format(year=r"\\d\{4\}", author=r"\.\*")
+            formatted = line.format(year=r"\\d\{4\}\(-\\d\{4\}\)\?", author=r"\.\*")
             regex_parts.append(convert_bre_to_regex(formatted))
     template_regex = "\n?".join(regex_parts)