Schema Printer Tests

* Implement remaining part of printer so that it can print Schema types.

Author: jhgg

graphql/core/language/printer.py

@@ -23,9 +23,11 @@ def leave_OperationDefinition(self, node, *args):
         selection_set = node.selection_set
         if not name:
             return selection_set
+
         op = node.operation
         defs = wrap('(', join(node.variable_definitions, ', '), ')')
         directives = join(node.directives, ' ')
+
         return join([op, join([name, defs]), directives, selection_set], ' ')
 
     def leave_VariableDefinition(self, node, *args):
@@ -104,6 +106,42 @@ def leave_ListType(self, node, *args):
     def leave_NonNullType(self, node, *args):
         return node.type + '!'
 
+    # Type Definitions:
+
+    def leave_ObjectTypeDefinition(self, node, *args):
+        return (
+            'type ' + node.name + ' ' +
+            wrap('implements ', join(node.interfaces, ', '), ' ') +
+            block(node.fields)
+        )
+
+    def leave_FieldDefinition(self, node, *args):
+        return node.name + wrap('(', join(node.arguments, ', '), ')') + ': ' + node.type
+
+    def leave_InputValueDefinition(self, node, *args):
+        return node.name + ': ' + node.type + wrap(' = ', node.default_value)
+
+    def leave_InterfaceTypeDefinition(self, node, *args):
+        return 'interface ' + node.name + ' ' + block(node.fields)
+
+    def leave_UnionTypeDefinition(self, node, *args):
+        return 'union ' + node.name + ' = ' + join(node.types, ' | ')
+
+    def leave_ScalarTypeDefinition(self, node, *args):
+        return 'scalar ' + node.name
+
+    def leave_EnumTypeDefinition(self, node, *args):
+        return 'enum ' + node.name + ' ' + block(node.values)
+
+    def leave_EnumValueDefinition(self, node, *args):
+        return node.name
+
+    def leave_InputObjectTypeDefinition(self, node, *args):
+        return 'input ' + node.name + ' ' + block(node.fields)
+
+    def leave_TypeExtensionDefinition(self, node, *args):
+        return 'extend ' + node.definition
+
 
 def join(maybe_list, separator=''):
     if maybe_list:

graphql/core/language/visitor_meta.py

@@ -32,7 +32,7 @@
 
     ast.ObjectTypeDefinition: ('name', 'interfaces', 'fields'),
     ast.FieldDefinition: ('name', 'arguments', 'type'),
-    ast.InputValueDefinition: ('name', 'type', 'defaultValue'),
+    ast.InputValueDefinition: ('name', 'type', 'default_value'),
     ast.InterfaceTypeDefinition: ('name', 'fields'),
     ast.UnionTypeDefinition: ('name', 'types'),
     ast.ScalarTypeDefinition: ('name',),

graphql/core/utils/type_info.py

@@ -1,6 +1,6 @@
 import six
 
-from ..language import ast, visitor_meta
+from ..language import visitor_meta
 from ..type.definition import (
     GraphQLInputObjectType,
     GraphQLList,

tests/core_language/test_schema_printer.py

@@ -0,0 +1,69 @@
+from copy import deepcopy
+from graphql.core import parse
+from pytest import raises
+from graphql.core.language.printer import print_ast
+from graphql.core.language import ast
+from .fixtures import SCHEMA_KITCHEN_SINK
+
+
+def test_prints_minimal_ast():
+    node = ast.ScalarTypeDefinition(
+        name=ast.Name('foo')
+    )
+
+    assert print_ast(node) == 'scalar foo'
+
+
+def test_print_produces_helpful_error_messages():
+    bad_ast = {'random': 'Data'}
+    with raises(AssertionError) as excinfo:
+        print_ast(bad_ast)
+
+    assert "Invalid AST Node: {'random': 'Data'}" in str(excinfo.value)
+
+
+def test_does_not_alter_ast():
+    ast = parse(SCHEMA_KITCHEN_SINK)
+    ast_copy = deepcopy(ast)
+    print_ast(ast)
+    assert ast == ast_copy
+
+
+def test_prints_kitchen_sink():
+    ast = parse(SCHEMA_KITCHEN_SINK)
+    printed = print_ast(ast)
+
+    expected = '''type Foo implements Bar {
+  one: Type
+  two(argument: InputType!): Type
+  three(argument: InputType, other: String): Int
+  four(argument: String = "string"): String
+  five(argument: [String] = ["string", "string"]): String
+  six(argument: InputType = {key: "value"}): Type
+}
+
+interface Bar {
+  one: Type
+  four(argument: String = "string"): String
+}
+
+union Feed = Story | Article | Advert
+
+scalar CustomScalar
+
+enum Site {
+  DESKTOP
+  MOBILE
+}
+
+input InputType {
+  key: String!
+  answer: Int = 42
+}
+
+extend type Foo {
+  seven(argument: [String]): Type
+}
+'''
+
+    assert printed == expected