GSoC Module A: week 5 : feat(harvester): add git diff retrieval pipeline (stacked on top of #986)

.gitignore

@@ -83,3 +83,5 @@ tmp/
 cres/*
 ### Local project management tooling
 project management scripts/
+
+.harvester_cache/

application/tests/harvester_test/__init__.py

@@ -0,0 +1,3 @@
+"""
+tests for Module A configuration layer (empty for now)
+"""

application/tests/harvester_test/change_detector_test.py

@@ -0,0 +1,52 @@
+import unittest
+from unittest.mock import MagicMock
+from unittest.mock import patch
+
+from application.utils.harvester.change_detector import (
+    ChangeDetector,
+)
+
+
+class ChangeDetectorTests(unittest.TestCase):
+    @patch("application.utils.harvester.change_detector.subprocess.run")
+    def test_get_modified_files_since(self, mock_run):
+        mock_run.return_value = MagicMock(
+            stdout="a.md\nb.md\na.md\n",
+        )
+
+        client = MagicMock()
+        detector = ChangeDetector(client)
+
+        files = detector.get_modified_files_since("abc123")
+
+        self.assertEqual(
+            files,
+            [
+                "a.md",
+                "b.md",
+            ],
+        )
+
+    @patch("application.utils.harvester.change_detector.subprocess.run")
+    def test_get_commits_since(self, mock_run):
+        mock_run.return_value = MagicMock(
+            stdout="111\n222\n333\n",
+        )
+
+        client = MagicMock()
+        detector = ChangeDetector(client)
+
+        commits = detector.get_commits_since("abc123")
+
+        self.assertEqual(
+            commits,
+            [
+                "111",
+                "222",
+                "333",
+            ],
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()

application/tests/harvester_test/checkpoint_store_test.py

@@ -0,0 +1,92 @@
+import unittest
+from datetime import datetime
+from pathlib import Path
+
+from application.utils.harvester.checkpoint_store import (
+    CheckpointStore,
+)
+from application.utils.harvester.models import (
+    RepositoryCheckpoint,
+)
+
+
+class CheckpointStoreTests(unittest.TestCase):
+    def test_save_and_load_checkpoint(self):
+        tmp_dir = Path(self._testMethodName)
+
+        try:
+            store = CheckpointStore(
+                tmp_dir / "checkpoints.json",
+            )
+
+            checkpoint = RepositoryCheckpoint(
+                repository_id="owasp-asvs",
+                last_processed_commit="abc123",
+                updated_at=datetime.now(),
+            )
+
+            store.save(checkpoint)
+
+            loaded = store.load("owasp-asvs")
+
+            if loaded is None:
+                self.fail("Checkpoint should have been loaded")
+
+            self.assertEqual(
+                loaded.last_processed_commit,
+                "abc123",
+            )
+
+        finally:
+            if tmp_dir.exists():
+                import shutil
+
+                shutil.rmtree(tmp_dir)
+
+    def test_load_missing_file(self):
+        tmp_dir = Path(self._testMethodName)
+
+        try:
+            store = CheckpointStore(
+                tmp_dir / "missing.json",
+            )
+
+            self.assertIsNone(
+                store.load("repo"),
+            )
+
+        finally:
+            if tmp_dir.exists():
+                import shutil
+
+                shutil.rmtree(tmp_dir)
+
+    def test_load_missing_repository(self):
+        tmp_dir = Path(self._testMethodName)
+
+        try:
+            store = CheckpointStore(
+                tmp_dir / "checkpoint.json",
+            )
+
+            store.save(
+                RepositoryCheckpoint(
+                    repository_id="repo-a",
+                    last_processed_commit="abc123",
+                    updated_at=datetime.now(),
+                )
+            )
+
+            self.assertIsNone(
+                store.load("repo-b"),
+            )
+
+        finally:
+            if tmp_dir.exists():
+                import shutil
+
+                shutil.rmtree(tmp_dir)
+
+
+if __name__ == "__main__":
+    unittest.main()

application/tests/harvester_test/config_loader_test.py

@@ -0,0 +1,63 @@
+from pathlib import Path
+import unittest
+
+from application.utils.harvester.config_loader import (
+    ConfigLoaderError,
+    ConfigFileNotFoundError,
+    load_repo_config,
+)
+
+FIXTURES_DIR = Path(__file__).parent / "fixtures"
+
+
+class ConfigLoaderTests(unittest.TestCase):
+    def test_load_valid_config(self):
+        config_path = FIXTURES_DIR / "valid_repos.yaml"
+
+        config = load_repo_config(config_path)
+
+        self.assertEqual(len(config.repositories), 1)
+
+        repo = config.repositories[0]
+
+        self.assertEqual(repo.id, "owasp-asvs")
+        self.assertEqual(repo.owner, "OWASP")
+        self.assertEqual(repo.repo, "ASVS")
+
+    def test_missing_repository_id(self):
+        config_path = FIXTURES_DIR / "invalid_missing_id.yaml"
+
+        with self.assertRaises(ConfigLoaderError):
+            load_repo_config(config_path)
+
+    def test_invalid_chunk_size(self):
+        config_path = FIXTURES_DIR / "invalid_chunk_size.yaml"
+
+        with self.assertRaisesRegex(ConfigLoaderError, "max_tokens"):
+            load_repo_config(config_path)
+
+    def test_invalid_yaml_syntax(self):
+        config_path = FIXTURES_DIR / "invalid_yaml.yaml"
+
+        with self.assertRaises(ConfigLoaderError):
+            load_repo_config(config_path)
+
+    def test_missing_config_file(self):
+        with self.assertRaises(ConfigFileNotFoundError):
+            load_repo_config("does_not_exist.yaml")
+
+    def test_invalid_polling_interval(self):
+        config_path = FIXTURES_DIR / "invalid_polling_interval.yaml"
+
+        with self.assertRaises(ConfigLoaderError):
+            load_repo_config(config_path)
+
+    def test_empty_include_paths(self):
+        config_path = FIXTURES_DIR / "empty_include_paths.yaml"
+
+        with self.assertRaises(ConfigLoaderError):
+            load_repo_config(config_path)
+
+
+if __name__ == "__main__":
+    unittest.main()

application/tests/harvester_test/diff_normalizer_test.py

@@ -0,0 +1,117 @@
+import unittest
+from datetime import datetime
+
+from application.utils.harvester.diff_normalizer import (
+    DiffNormalizer,
+)
+
+from application.utils.harvester.models import (
+    DiffBlock,
+)
+
+
+DIFF_METADATA = {
+    "repository": "OWASP/ASVS",
+    "commit_sha": "abc123",
+    "committed_at": datetime(2026, 1, 1),
+}
+
+
+class DiffNormalizerTests(unittest.TestCase):
+    def test_whitespace_normalization(self):
+        normalizer = DiffNormalizer()
+
+        blocks = [
+            DiffBlock(
+                file_path="README.md",
+                added_lines=[
+                    "     Hello      World      ",
+                    "\t\tTabs\t\tEverywhere\t",
+                    "",
+                    "     ",
+                    "Unicode\u00a0Space",
+                    "Mix\t of\t tabs   and    spaces",
+                    "   Multiple     words      together   ",
+                    "\u00a0\u00a0Leading unicode spaces\u00a0",
+                    "   ## Authentication   ",
+                    "   -   Use MFA   ",
+                    "   `inline code`   ",
+                    "   **Important**   ",
+                ],
+                **DIFF_METADATA,
+            )
+        ]
+
+        result = normalizer.normalize(blocks)
+
+        self.assertEqual(
+            result[0].added_lines,
+            [
+                "Hello World",
+                "Tabs Everywhere",
+                "Unicode Space",
+                "Mix of tabs and spaces",
+                "Multiple words together",
+                "Leading unicode spaces",
+                "## Authentication",
+                "- Use MFA",
+                "`inline code`",
+                "**Important**",
+            ],
+        )
+
+    def test_remove_empty_lines(self):
+        normalizer = DiffNormalizer()
+
+        blocks = [
+            DiffBlock(
+                file_path="README.md",
+                added_lines=[
+                    "",
+                    "   ",
+                    "Hello",
+                ],
+                **DIFF_METADATA,
+            )
+        ]
+
+        result = normalizer.normalize(blocks)
+
+        self.assertEqual(
+            result[0].added_lines,
+            [
+                "Hello",
+            ],
+        )
+
+    def test_multiple_blocks(self):
+        normalizer = DiffNormalizer()
+
+        blocks = [
+            DiffBlock(
+                file_path="a.md",
+                added_lines=["  One  "],
+                **DIFF_METADATA,
+            ),
+            DiffBlock(
+                file_path="b.md",
+                added_lines=["  Two  "],
+                **DIFF_METADATA,
+            ),
+        ]
+
+        result = normalizer.normalize(blocks)
+
+        self.assertEqual(
+            result[0].added_lines,
+            ["One"],
+        )
+
+        self.assertEqual(
+            result[1].added_lines,
+            ["Two"],
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()