captions improvements

test/test_metadata_writer.py

@@ -21,6 +21,16 @@ def make_dng_file(tmp_path):
     return _make
 
 
+@pytest.fixture
+def metadata_writer_on_existing(make_dng_file):
+    metadata_writer = MetadataWriter(make_dng_file(PATHS_DNG_EXAMPLES[0]))
+    metadata_writer.write_caption(
+        "Let's pretend this is the caption of the original image",
+        include_prefix=False,
+    )
+    return metadata_writer
+
+
 @pytest.mark.parametrize("pic", PATHS_DNG_EXAMPLES)
 def test_read_metadata(make_dng_file, pic):
     """primitive test for `MetadataWriter`"""
@@ -49,22 +59,47 @@ def test_is_prefixed():
 def test_read_metadata_sidecar_path(make_dng_file, pic):
     file_path = make_dng_file(pic)
     metadata_writer = MetadataWriter(file_path)
-    print(metadata_writer.sidecar_path)
     assert isinstance(metadata_writer.sidecar_path, Path)
     assert str(metadata_writer.sidecar_path).lower().endswith(".dng.xmp")
 
+    # file does not exits yet, only the name
+    assert not metadata_writer.sidecar_path.exists()
+
 
 @pytest.mark.parametrize("pic", PATHS_DNG_EXAMPLES)
 def test_set_caption(make_dng_file, pic):
     metadata_writer = MetadataWriter(make_dng_file(pic))
+    assert not metadata_writer.sidecar_path.exists()  # sidecar does not exist yet ...
     metadata_writer.write_caption("This is a test")
+    assert metadata_writer.sidecar_path.exists()  # ... but now!
     result = metadata_writer.get_caption()
     assert result
+    assert result == "photools: This is a test"
 
 
-def test_set_caption_on_existing():
-    # TODO
-    ...
+def test_set_caption_on_existing(metadata_writer_on_existing):
+    assert (
+        metadata_writer_on_existing.get_caption()
+        == "Let's pretend this is the caption of the original image"
+    )
+
+    metadata_writer_on_existing.write_caption("Another caption")
+    assert (
+        metadata_writer_on_existing.get_caption()
+        == "Let's pretend this is the caption of the original image. photools: Another caption"
+    )
+
+    metadata_writer_on_existing.write_caption("Updated caption")
+    assert (
+        metadata_writer_on_existing.get_caption()
+        == "Let's pretend this is the caption of the original image. photools: Updated caption"
+    )
+
+    metadata_writer_on_existing.write_caption("Don't do this!", override=False)
+    assert (
+        metadata_writer_on_existing.get_caption()
+        == "Let's pretend this is the caption of the original image. photools: Updated caption"
+    )
 
 
 @pytest.mark.parametrize("pic", PATHS_DNG_EXAMPLES)