Comment in VariablesAreInputTypesRule

Author: mjmahone

src/validation/ValidationContext.ts

@@ -35,6 +35,7 @@ interface VariableUsage {
   readonly node: VariableNode;
   readonly type: Maybe<GraphQLInputType>;
   readonly defaultValue: Maybe<unknown>;
+  readonly argumentDefinition: Maybe<VariableDefinitionNode>;
 }
 interface DefinedVariable {
   readonly variableDefinition: VariableDefinitionNode;
@@ -151,7 +152,9 @@ export class ASTValidationContext {
       const variableDefinedOperations: ObjMap<Array<DefinedVariable>> = {};
       visit(this._ast, {
         OperationDefinition(operation) {
-          for (const varDef of operation.variableDefinitions ?? []) {
+          /* c8 ignore next */
+          const variableDefinitions = operation.variableDefinitions ?? [];
+          for (const varDef of variableDefinitions) {
             if (!variableDefinedOperations[varDef.variable.name.value]) {
               variableDefinedOperations[varDef.variable.name.value] = [];
             }
@@ -238,10 +241,18 @@ export class ValidationContext extends ASTValidationContext {
         visitWithTypeInfo(typeInfo, {
           VariableDefinition: () => false,
           Variable(variable) {
+            const argumentDefinition =
+              node.kind === Kind.FRAGMENT_DEFINITION
+                ? node.argumentDefinitions?.find(
+                    (argDef) =>
+                      argDef.variable.name.value === variable.name.value,
+                  )
+                : undefined;
             newUsages.push({
               node: variable,
               type: typeInfo.getInputType(),
               defaultValue: typeInfo.getDefaultValue(),
+              argumentDefinition,
             });
           },
         }),

src/validation/__tests__/VariablesInAllowedPositionRule-test.ts

@@ -356,6 +356,13 @@ describe('Validate: Variables are in allowed positions', () => {
           dog @include(if: $boolVar)
         }`);
     });
+
+    it('undefined in directive with default value with option', () => {
+      expectValid(`
+        {
+          dog @include(if: $x)
+        }`);
+    });
   });
 
   describe('Fragment arguments are validated', () => {
@@ -373,12 +380,26 @@ describe('Validate: Variables are in allowed positions', () => {
       `);
     });
 
+    it('Boolean => Boolean with default value', () => {
+      expectValid(`
+        query Query($booleanArg: Boolean)
+        {
+          complicatedArgs {
+            ...A(b: $booleanArg)
+          }
+        }
+        fragment A($b: Boolean = true) on ComplicatedArgs {
+          booleanArgField(booleanArg: $b)
+        }
+      `);
+    });
+
     it('Boolean => Boolean!', () => {
       expectErrors(`
-        query Query($fb: Boolean)
+        query Query($ab: Boolean)
         {
           complicatedArgs {
-            ...A(b: $fb)
+            ...A(b: $ab)
           }
         }
         fragment A($b: Boolean!) on ComplicatedArgs {
@@ -387,10 +408,10 @@ describe('Validate: Variables are in allowed positions', () => {
       `).toDeepEqual([
         {
           message:
-            'Variable "$booleanArg" of type "Boolean" used in position expecting type "Boolean!".',
+            'Variable "$ab" of type "Boolean" used in position expecting type "Boolean!".',
           locations: [
             { line: 2, column: 21 },
-            { line: 4, column: 47 },
+            { line: 5, column: 21 },
           ],
         },
       ]);
@@ -412,7 +433,7 @@ describe('Validate: Variables are in allowed positions', () => {
             'Variable "$intVar" of type "Int" used in position expecting type "Int!".',
           locations: [
             { line: 2, column: 21 },
-            { line: 4, column: 47 },
+            { line: 4, column: 21 },
           ],
         },
       ]);

src/validation/rules/NoUndefinedVariablesRule.ts

@@ -22,7 +22,10 @@ export function NoUndefinedVariablesRule(
       );
 
       const usages = context.getRecursiveVariableUsages(operation);
-      for (const { node } of usages) {
+      for (const { node, argumentDefinition } of usages) {
+        if (argumentDefinition) {
+          continue;
+        }
         const varName = node.name.value;
         if (!variableNameDefined.has(varName)) {
           context.reportError(

src/validation/rules/VariablesAreInputTypesRule.ts

@@ -16,6 +16,8 @@ import type { ValidationContext } from '../ValidationContext.js';
  * A GraphQL operation is only valid if all the variables it defines are of
  * input types (scalar, enum, or input object).
  *
+ * Similarly, all fragment defined arguments must be of input types.
+ *
  * See https://spec.graphql.org/draft/#sec-Variables-Are-Input-Types
  */
 export function VariablesAreInputTypesRule(