feat: Support dedent/cleandoc for Field description

Issue-50: #50
PR-52: #52

Author: analog-cbarber

src/griffe_pydantic/_internal/static.py

@@ -31,6 +31,35 @@
 _logger = get_logger("griffe_pydantic")
 
 
+def _extract_description(description: Expr | str) -> str | None:
+    """Extract a description value from a Field argument.
+
+    Handles plain string literals as well as calls to textwrap.dedent() and inspect.cleandoc().
+
+    Parameters:
+        description: The description expression from a Field call.
+
+    Returns:
+        The extracted description string, or None if it cannot be extracted.
+    """
+    # If it's a call to dedent() or cleandoc(), extract the first argument.
+    if (
+        isinstance(description, ExprCall)
+        and description.function.canonical_path in ("textwrap.dedent", "inspect.cleandoc")
+        and description.arguments
+    ):
+        description = description.arguments[0]
+
+    # For plain strings, just evaluate them.
+    if isinstance(description, str):
+        try:
+            return ast.literal_eval(description)
+        except ValueError:
+            pass
+
+    return None
+
+
 def _inherits_pydantic(cls: Class) -> bool:
     """Tell whether a class inherits from a Pydantic model.
 
@@ -164,10 +193,10 @@ def _process_attribute(attr: Attribute, cls: Class, *, processed: set[str]) -> N
     attr.extra[common._self_namespace]["constraints"] = constraints
 
     # Populate docstring from the field's `description` argument.
-    if not attr.docstring and (docstring := kwargs.get("description")):
-        try:
-            attr.docstring = Docstring(ast.literal_eval(docstring), parent=attr)  # ty: ignore[invalid-argument-type]
-        except ValueError:
+    if not attr.docstring and (description_expr := kwargs.get("description")):
+        if description_text := _extract_description(description_expr):
+            attr.docstring = Docstring(description_text, parent=attr)
+        else:
             _logger.debug(f"Could not parse description of field '{attr.path}' as literal, skipping")
 
 

tests/test_extension.py

@@ -296,3 +296,94 @@ class Model(BaseModel):
     ) as package:
         assert "pydantic-field" in package["Model.field"].labels
         assert "pydantic-field" not in package["Model._private"].labels
+
+
+def test_field_description_with_dedent() -> None:
+    """Test that field descriptions wrapped in textwrap.dedent() are extracted."""
+    code = """
+    from textwrap import dedent
+    from pydantic import BaseModel, Field
+
+    class Model(BaseModel):
+        field1: int = Field(
+            description=dedent('''
+                This is a multiline description.
+                With multiple lines.
+            ''')
+        )
+        field2: str = Field(default="test", description=dedent("Single line dedented."))
+    """
+    with temporary_visited_package(
+        "package",
+        modules={"__init__.py": code},
+        extensions=Extensions(PydanticExtension(schema=False)),
+    ) as package:
+        assert package["Model.field1"].is_attribute
+        assert "pydantic-field" in package["Model.field1"].labels
+        assert package["Model.field1"].docstring is not None
+        assert "This is a multiline description." in package["Model.field1"].docstring.value
+        assert "With multiple lines." in package["Model.field1"].docstring.value
+
+        assert package["Model.field2"].is_attribute
+        assert "pydantic-field" in package["Model.field2"].labels
+        assert package["Model.field2"].docstring is not None
+        assert package["Model.field2"].docstring.value == "Single line dedented."
+
+
+def test_field_description_with_cleandoc() -> None:
+    """Test that field descriptions wrapped in inspect.cleandoc() are extracted."""
+    code = """
+    from inspect import cleandoc
+    from pydantic import BaseModel, Field
+
+    class Model(BaseModel):
+        field1: int = Field(
+            description=cleandoc('''
+                This is a multiline description.
+                With multiple lines.
+            ''')
+        )
+        field2: str = Field(default="test", description=cleandoc("Single line cleandoc."))
+    """
+    with temporary_visited_package(
+        "package",
+        modules={"__init__.py": code},
+        extensions=Extensions(PydanticExtension(schema=False)),
+    ) as package:
+        assert package["Model.field1"].is_attribute
+        assert "pydantic-field" in package["Model.field1"].labels
+        assert package["Model.field1"].docstring is not None
+        assert "This is a multiline description." in package["Model.field1"].docstring.value
+        assert "With multiple lines." in package["Model.field1"].docstring.value
+
+        assert package["Model.field2"].is_attribute
+        assert "pydantic-field" in package["Model.field2"].labels
+        assert package["Model.field2"].docstring is not None
+        assert package["Model.field2"].docstring.value == "Single line cleandoc."
+
+
+def test_field_description_with_annotated_and_dedent() -> None:
+    """Test that field descriptions with Annotated and dedent() are extracted."""
+    code = """
+    from textwrap import dedent
+    from pydantic import BaseModel, Field
+    from typing import Annotated
+
+    class Model(BaseModel):
+        field1: Annotated[int, Field(
+            description=dedent('''
+                This is a multiline description.
+                With multiple lines.
+            ''')
+        )]
+    """
+    with temporary_visited_package(
+        "package",
+        modules={"__init__.py": code},
+        extensions=Extensions(PydanticExtension(schema=False)),
+    ) as package:
+        assert package["Model.field1"].is_attribute
+        assert "pydantic-field" in package["Model.field1"].labels
+        assert package["Model.field1"].docstring is not None
+        assert "This is a multiline description." in package["Model.field1"].docstring.value
+        assert "With multiple lines." in package["Model.field1"].docstring.value