Add missing documentation (#134)

Author: Cito

docs/modules/language.rst

@@ -73,6 +73,18 @@ Directive locations are specified using the following enumeration:
 
 .. autoclass:: DirectiveLocation
 
+You can also check the type of nodes with the following predicates:
+
+.. autofunction:: is_definition_node
+.. autofunction:: is_executable_definition_node
+.. autofunction:: is_selection_node
+.. autofunction:: is_value_node
+.. autofunction:: is_type_node
+.. autofunction:: is_type_system_definition_node
+.. autofunction:: is_type_definition_node
+.. autofunction:: is_type_system_extension_node
+.. autofunction:: is_type_extension_node
+
 Lexer
 -----
 
@@ -94,6 +106,11 @@ Parser
 .. autofunction:: parse_type
 .. autofunction:: parse_value
 
+Printer
+-------
+
+.. autofunction:: print_ast
+
 Source
 ------
 

src/graphql/language/predicates.py

@@ -25,36 +25,45 @@
 
 
 def is_definition_node(node: Node) -> bool:
+    """Check whether the given node represents a definition."""
     return isinstance(node, DefinitionNode)
 
 
 def is_executable_definition_node(node: Node) -> bool:
+    """Check whether the given node represents an executable definition."""
     return isinstance(node, ExecutableDefinitionNode)
 
 
 def is_selection_node(node: Node) -> bool:
+    """Check whether the given node represents a selection."""
     return isinstance(node, SelectionNode)
 
 
 def is_value_node(node: Node) -> bool:
+    """Check whether the given node represents a value."""
     return isinstance(node, ValueNode)
 
 
 def is_type_node(node: Node) -> bool:
+    """Check whether the given node represents a type."""
     return isinstance(node, TypeNode)
 
 
 def is_type_system_definition_node(node: Node) -> bool:
+    """Check whether the given node represents a type system definition."""
     return isinstance(node, TypeSystemDefinitionNode)
 
 
 def is_type_definition_node(node: Node) -> bool:
+    """Check whether the given node represents a type definition."""
     return isinstance(node, TypeDefinitionNode)
 
 
 def is_type_system_extension_node(node: Node) -> bool:
+    """Check whether the given node represents a type system extension."""
     return isinstance(node, (SchemaExtensionNode, TypeExtensionNode))
 
 
 def is_type_extension_node(node: Node) -> bool:
+    """Check whether the given node represents a type extension."""
     return isinstance(node, TypeExtensionNode)

tests/utilities/test_print_schema.py

@@ -504,7 +504,7 @@ def prints_custom_scalar():
             """
         )
 
-    def prints_custom_scalar_with_speicified_by_url():
+    def prints_custom_scalar_with_specified_by_url():
         foo_type = GraphQLScalarType(
             name="Foo", specified_by_url="https://example.com/foo_spec"
         )