add dynamodb collection

layercake/tests/test_jsonl.py

@@ -0,0 +1,19 @@
+import tempfile
+from pathlib import Path
+
+import layercake.jsonl as jsonl
+
+
+def test_readlines():
+    with tempfile.NamedTemporaryFile() as fp:
+        fp.writelines([b'{}\n' for _ in range(4)])
+        fp.seek(0)
+
+        with jsonl.readlines(fp.name) as lines:
+            assert sum(1 for _ in lines) == 4
+
+    with jsonl.readlines(Path('notfound.jsonl')) as lines:
+        assert sum(1 for _ in lines) == 0
+
+    with jsonl.readlines(Path('notfound.jsonl')) as lines:
+        assert list(lines) == []