improve upgrade path for new custom scalar parseConstLiteral() method

src/type/__tests__/definition-test.ts

@@ -72,22 +72,23 @@ describe('Type System: Scalars', () => {
     expect(scalar.serialize).to.equal(identityFunc);
     expect(scalar.parseValue).to.equal(identityFunc);
     expect(scalar.parseLiteral).to.be.a('function');
-    expect(scalar.parseConstLiteral).to.be.a('function');
+    /* default will be provided in v18 when parseLiteral is removed */
+    // expect(scalar.parseConstLiteral).to.be.a('function');
   });
 
-  it('use parseValue for parsing literals if parseConstLiteral omitted', () => {
+  it('use parseValue for parsing literals if parseLiteral omitted', () => {
     const scalar = new GraphQLScalarType({
       name: 'Foo',
       parseValue(value) {
         return 'parseValue: ' + inspect(value);
       },
     });
 
-    expect(scalar.parseConstLiteral(parseConstValue('null'))).to.equal(
+    expect(scalar.parseLiteral(parseConstValue('null'), undefined)).to.equal(
       'parseValue: null',
     );
     expect(
-      scalar.parseConstLiteral(parseConstValue('{ foo: "bar" }')),
+      scalar.parseLiteral(parseConstValue('{ foo: "bar" }'), undefined),
     ).to.equal('parseValue: { foo: "bar" }');
   });
 

src/type/__tests__/scalars-test.ts

@@ -66,6 +66,7 @@ describe('Type System: Specified scalar types', () => {
 
     it('parseConstLiteral', () => {
       function parseConstLiteral(str: string) {
+        /* @ts-expect-error to be removed in v18 when all custom scalars will have default method */
         return GraphQLInt.parseConstLiteral(parseConstValue(str));
       }
 
@@ -228,6 +229,7 @@ describe('Type System: Specified scalar types', () => {
 
     it('parseConstLiteral', () => {
       function parseConstLiteral(str: string) {
+        /* @ts-expect-error to be removed in v18 when all custom scalars will have default method */
         return GraphQLFloat.parseConstLiteral(parseConstValue(str));
       }
 
@@ -338,6 +340,7 @@ describe('Type System: Specified scalar types', () => {
 
     it('parseConstLiteral', () => {
       function parseConstLiteral(str: string) {
+        /* @ts-expect-error to be removed in v18 when all custom scalars will have default method */
         return GraphQLString.parseConstLiteral(parseConstValue(str));
       }
 
@@ -447,6 +450,7 @@ describe('Type System: Specified scalar types', () => {
 
     it('parseConstLiteral', () => {
       function parseConstLiteral(str: string) {
+        /* @ts-expect-error to be removed in v18 when all custom scalars will have default method */
         return GraphQLBoolean.parseConstLiteral(parseConstValue(str));
       }
 
@@ -559,6 +563,7 @@ describe('Type System: Specified scalar types', () => {
 
     it('parseConstLiteral', () => {
       function parseConstLiteral(str: string) {
+        /* @ts-expect-error to be removed in v18 when all custom scalars will have default method */
         return GraphQLID.parseConstLiteral(parseConstValue(str));
       }
 

src/type/definition.ts

@@ -588,7 +588,7 @@ export class GraphQLScalarType<TInternal = unknown, TExternal = TInternal> {
   parseValue: GraphQLScalarValueParser<TInternal>;
   /** @deprecated use `replaceVariables()` and `parseConstLiteral()` instead, `parseLiteral()` will be deprecated in v18 */
   parseLiteral: GraphQLScalarLiteralParser<TInternal>;
-  parseConstLiteral: GraphQLScalarConstLiteralParser<TInternal>;
+  parseConstLiteral: GraphQLScalarConstLiteralParser<TInternal> | undefined;
   valueToLiteral: GraphQLScalarValueToLiteral | undefined;
   extensions: Readonly<GraphQLScalarTypeExtensions>;
   astNode: Maybe<ScalarTypeDefinitionNode>;
@@ -608,9 +608,7 @@ export class GraphQLScalarType<TInternal = unknown, TExternal = TInternal> {
     this.parseLiteral =
       config.parseLiteral ??
       ((node, variables) => parseValue(valueFromASTUntyped(node, variables)));
-    this.parseConstLiteral =
-      config.parseConstLiteral ??
-      ((node) => parseValue(valueFromASTUntyped(node)));
+    this.parseConstLiteral = config.parseConstLiteral;
     this.valueToLiteral = config.valueToLiteral;
     this.extensions = toObjMap(config.extensions);
     this.astNode = config.astNode;
@@ -708,7 +706,7 @@ interface GraphQLScalarTypeNormalizedConfig<TInternal, TExternal>
   serialize: GraphQLScalarSerializer<TExternal>;
   parseValue: GraphQLScalarValueParser<TInternal>;
   parseLiteral: GraphQLScalarLiteralParser<TInternal>;
-  parseConstLiteral: GraphQLScalarConstLiteralParser<TInternal>;
+  parseConstLiteral: GraphQLScalarConstLiteralParser<TInternal> | undefined;
   extensions: Readonly<GraphQLScalarTypeExtensions>;
   extensionASTNodes: ReadonlyArray<ScalarTypeExtensionNode>;
 }

src/utilities/coerceInputValue.ts

@@ -371,14 +371,12 @@ export function coerceInputLiteral(
   }
 
   const leafType = assertLeafType(type);
-  const constValueNode = replaceVariables(
-    valueNode,
-    variableValues,
-    fragmentVariableValues,
-  );
-
   try {
-    return leafType.parseConstLiteral(constValueNode);
+    return leafType.parseConstLiteral
+      ? leafType.parseConstLiteral(
+          replaceVariables(valueNode, variableValues, fragmentVariableValues),
+        )
+      : leafType.parseLiteral(valueNode, variableValues?.coerced);
   } catch (_error) {
     // Invalid: ignore error and intentionally return no value.
   }

src/validation/rules/ValuesOfCorrectTypeRule.ts

@@ -153,12 +153,12 @@ function isValidValueNode(context: ValidationContext, node: ValueNode): void {
     return;
   }
 
-  const constValueNode = replaceVariables(node);
-
   // Scalars and Enums determine if a literal value is valid via parseConstLiteral(),
   // which may throw or return undefined to indicate an invalid value.
   try {
-    const parseResult = type.parseConstLiteral(constValueNode);
+    const parseResult = type.parseConstLiteral
+      ? type.parseConstLiteral(replaceVariables(node))
+      : type.parseLiteral(node, undefined);
     if (parseResult === undefined) {
       const typeStr = inspect(locationType);
       context.reportError(