Add tests for Pipe.label_data

spacy/tests/pipeline/test_pipe_methods.py

@@ -1,6 +1,6 @@
 import pytest
 from spacy.language import Language
-from spacy.util import SimpleFrozenList
+from spacy.util import SimpleFrozenList, get_arg_names
 
 
 @pytest.fixture
@@ -346,3 +346,34 @@ def test_pipe_methods_frozen():
         nlp.components.sort()
     with pytest.raises(NotImplementedError):
         nlp.component_names.clear()
+
+
+@pytest.mark.parametrize(
+    "pipe",
+    [
+        "tagger",
+        "parser",
+        "ner",
+        "textcat",
+        pytest.param("morphologizer", marks=pytest.mark.xfail),
+    ],
+)
+def test_pipe_label_data_exports_labels(pipe):
+    nlp = Language()
+    pipe = nlp.add_pipe(pipe)
+    # Make sure pipe has pipe labels
+    assert getattr(pipe, "label_data", None) is not None
+    # Make sure pipe can be initialized with labels
+    initialize = getattr(pipe, "initialize", None)
+    assert initialize is not None
+    assert "labels" in get_arg_names(initialize)
+
+
+@pytest.mark.parametrize("pipe", ["senter", "entity_linker"])
+def test_pipe_label_data_no_labels(pipe):
+    nlp = Language()
+    pipe = nlp.add_pipe(pipe)
+    assert getattr(pipe, "label_data", None) is None
+    initialize = getattr(pipe, "initialize", None)
+    if initialize is not None:
+        assert "labels" not in get_arg_names(initialize)