Add tests for Python docstring highlighting

tests/query/highlights/python/docstrings.py

@@ -0,0 +1,111 @@
+# Docstrings according to PEP 257 (https://peps.python.org/pep-0257/)
+# <- @comment
+
+"""Module docstring assigned to `__doc__`..."""
+# <- @string.documentation
+"""
+... with an addtional docstring, not part of `__doc__`.
+"""
+# <- @string.documentation
+
+"""
+Some random docstring in the middle if nowhere...
+"""
+# <- @string.documentation
+"""
+... also with not one ...
+"""
+# <- @string.documentation
+"""
+... but two addtional docstrings.
+"""
+# <- @string.documentation
+
+oneline_string_assignment = "not detected as docstring"
+#                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^ @string
+#                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^ !@string.documentation
+"""Module attribute docstring."""
+# <- @string.documentation
+
+multiline_string_assignment = """
+                              also not detected as docstring
+                              """
+#                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @string
+#                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ !@string.documentation
+
+multiline_string_in_brackets = (
+    "not "
+    # <- @string
+    # <- !@string.documentation
+    "detected "
+    # <- @string
+    # <- !@string.documentation
+    "as docstring, "
+    # <- @string
+    # <- !@string.documentation
+    "either."
+    # <- @string
+    # <- !@string.documentation
+)
+
+
+class A:
+    """
+    Class docstring, assigned to `__doc__`.
+    """
+    # <- @string.documentation
+
+    """
+    Some random docstring again, ...
+    """
+    # <- @string.documentation
+    """
+    ... with an "additional" docstring. Again.
+    """
+    # <- @string.documentation
+
+    foo = "class attribute"
+    #     ^^^^^^^^^^^^^^^^^ @string
+    #     ^^^^^^^^^^^^^^^^^ !@string.documentation
+    """
+    Class attribute docstring, but an attribute 
+    does not have a `__doc__` attribute itself.
+    """
+    # <- @string.documentation
+
+    bar: int
+    """Class attribute docstring, type annotation only."""
+    # <- @string.documentation
+
+    baz: str = "type annotated class attribute"
+    #          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @string
+    #          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ !@string.documentation
+    """Class attribute docstring, type annotation and assignment."""
+    # <- @string.documentation
+
+    def __init__(self):
+        """Method docstring."""
+        # <- @string.documentation
+
+        self.quux = "instance attribute"
+        #           ^^^^^^^^^^^^^^^^^^^^ @string
+        #           ^^^^^^^^^^^^^^^^^^^^ !@string.documentation
+        """Instance attribute docstring."""
+        # <- @string.documentation
+
+
+def f(x):
+    """Function docstring."""
+    # <- @string.documentation
+    """Addtional function docstring."""
+    # <- @string.documentation
+    return x**2
+
+
+f.a = 1
+"""Function attribute docstring."""
+# <- @string.documentation
+
+
+"Random docstring with single quotes - legal, but far off standard and confusing."
+# <- @string.documentation