Fix TSC errors

src/error/GraphQLError.ts

@@ -98,8 +98,10 @@ export class GraphQLError extends Error {
       _source = _nodes[0].loc?.source;
     }
 
-    let _positions = positions;
-    if (!_positions && _nodes) {
+    let _positions;
+    if (positions) {
+      _positions = positions;
+    } else if (_nodes) {
       _positions = [];
       for (const node of _nodes) {
         if (node.loc) {
@@ -131,7 +133,6 @@ export class GraphQLError extends Error {
       }
     }
 
-    // @ts-expect-error FIXME
     Object.defineProperties(this, {
       name: { value: 'GraphQLError' },
       message: {
@@ -210,7 +211,6 @@ export class GraphQLError extends Error {
   }
 
   // FIXME: workaround to not break chai comparisons, should be remove in v16
-  // @ts-expect-error Flow doesn't support computed properties yet
   get [Symbol.toStringTag](): string {
     return 'Object';
   }

src/error/__tests__/formatError-test.ts

@@ -45,12 +45,10 @@ describe('formatError: default error formatter', () => {
   });
 
   it('rejects null and undefined errors', () => {
-    // @ts-expect-error
     expect(() => formatError(undefined)).to.throw(
       'Received null or undefined error.',
     );
 
-    // @ts-expect-error
     expect(() => formatError(null)).to.throw(
       'Received null or undefined error.',
     );

src/error/locatedError.ts

@@ -22,6 +22,7 @@ export function locatedError(
       : new Error('Unexpected error value: ' + inspect(rawOriginalError));
 
   // Note: this uses a brand-check to support GraphQL errors originating from other contexts.
+  // @ts-expect-error FIXME: TS Conversion
   if (Array.isArray(originalError.path)) {
     // @ts-expect-error
     return originalError;

src/execution/execute.ts

@@ -191,7 +191,9 @@ export function execute(args: ExecutionArgs): PromiseOrValue<ExecutionResult> {
   // field and its descendants will be omitted, and sibling fields will still
   // be executed. An execution which encounters errors will still result in a
   // resolved Promise.
+  // @ts-expect-error FIXME: TS Conversion
   const data = executeOperation(exeContext, exeContext.operation, rootValue);
+  // @ts-expect-error FIXME: TS Conversion
   return buildResponse(exeContext, data);
 }
 
@@ -313,7 +315,6 @@ export function buildExecutionContext(
     return coercedVariableValues.errors;
   }
 
-  // @ts-expect-error
   return {
     schema,
     fragments,
@@ -1078,7 +1079,7 @@ function _collectSubfields(
   fieldNodes: ReadonlyArray<FieldNode>,
 ): Map<string, Array<FieldNode>> {
   let subFieldNodes = new Map();
-  const visitedFragmentNames = new Set();
+  const visitedFragmentNames = new Set<string>();
   for (const node of fieldNodes) {
     if (node.selectionSet) {
       subFieldNodes = collectFields(

src/jsutils/__tests__/identityFunc-test.ts

@@ -5,6 +5,7 @@ import { identityFunc } from '../identityFunc';
 
 describe('identityFunc', () => {
   it('returns the first argument it receives', () => {
+    // @ts-expect-error
     expect(identityFunc()).to.equal(undefined);
     expect(identityFunc(undefined)).to.equal(undefined);
     expect(identityFunc(null)).to.equal(null);

src/jsutils/__tests__/inspect-test.ts

@@ -124,7 +124,7 @@ describe('inspect', () => {
   });
 
   it('detect circular objects', () => {
-    const obj = {};
+    const obj: { [name: string]: unknown } = {};
     obj.self = obj;
     obj.deepSelf = { self: obj };
 
@@ -165,7 +165,6 @@ describe('inspect', () => {
 
     expect(inspect([[new Foo()]])).to.equal('[[[Foo]]]');
 
-    // @ts-expect-error
     Foo.prototype[Symbol.toStringTag] = 'Bar';
     expect(inspect([[new Foo()]])).to.equal('[[[Bar]]]');
 

src/jsutils/__tests__/isIterableObject-test.ts

@@ -60,7 +60,7 @@ describe('isIterableObject', () => {
     };
     expect(isIterableObject(invalidIterable)).to.equal(false);
 
-    const arrayLike = {};
+    const arrayLike: { [key: string]: unknown } = {};
     arrayLike[0] = 'Alpha';
     arrayLike[1] = 'Bravo';
     arrayLike[2] = 'Charlie';

src/jsutils/inspect.ts

@@ -35,7 +35,9 @@ function formatObjectValue(
 
   const seenValues = [...previouslySeenValues, value];
 
+  // @ts-expect-error FIXME: TS Conversion
   if (typeof value.toJSON === 'function') {
+    // @ts-expect-error FIXME: TS Conversion
     const jsonValue = (value.toJSON as () => unknown)();
 
     // check for infinite recursion

src/jsutils/isPromise.ts

@@ -3,5 +3,6 @@
  * otherwise returns false.
  */
 export function isPromise(value: unknown): value is Promise<unknown> {
-  return typeof value?.then === 'function';
+  // eslint-disable-next-line @typescript-eslint/dot-notation
+  return typeof value?.['then'] === 'function';
 }

src/language/__tests__/printer-test.ts

@@ -9,7 +9,10 @@ import { print } from '../printer';
 
 describe('Printer: Query document', () => {
   it('prints minimal ast', () => {
-    const ast = { kind: 'Field', name: { kind: 'Name', value: 'foo' } };
+    const ast = {
+      kind: 'Field',
+      name: { kind: 'Name', value: 'foo' },
+    } as const;
     expect(print(ast)).to.equal('foo');
   });
 

src/language/__tests__/schema-printer-test.ts

@@ -12,7 +12,7 @@ describe('Printer: SDL document', () => {
     const ast = {
       kind: 'ScalarTypeDefinition',
       name: { kind: 'Name', value: 'foo' },
-    };
+    } as const;
     expect(print(ast)).to.equal('scalar foo');
   });
 

src/language/__tests__/toJSONDeep.ts

@@ -11,7 +11,6 @@ export function toJSONDeep(value: unknown): unknown {
   }
 
   if (typeof value.toJSON === 'function') {
-    // @ts-expect-error
     return value.toJSON();
   }
 

src/language/__tests__/visitor-test.ts

@@ -4,6 +4,7 @@ import { describe, it } from 'mocha';
 import { kitchenSinkQuery } from '../../__testUtils__/kitchenSinkQuery';
 
 import type { ASTNode } from '../ast';
+import { isNode } from '../ast';
 import { Kind } from '../kinds';
 import { parse } from '../parser';
 import { visit, visitInParallel, BREAK } from '../visitor';
@@ -50,6 +51,7 @@ function checkVisitorFnArgs(ast: any, args: any, isEdited: boolean = false) {
 }
 
 function getValue(node: ASTNode) {
+  // @ts-expect-error FIXME
   return node.value != null ? node.value : undefined;
 }
 
@@ -263,6 +265,7 @@ describe('Visitor', () => {
         if (node.kind === 'Field' && node.name.value === 'a') {
           return {
             kind: 'Field',
+            // @ts-expect-error FIXME
             selectionSet: [addedField].concat(node.selectionSet),
           };
         }
@@ -522,7 +525,7 @@ describe('Visitor', () => {
           'enter',
           node.kind,
           key,
-          parent?.kind != null ? parent.kind : undefined,
+          isNode(parent) ? parent.kind : undefined,
         ]);
 
         checkVisitorFnArgs(ast, arguments);
@@ -534,7 +537,7 @@ describe('Visitor', () => {
           'leave',
           node.kind,
           key,
-          parent?.kind != null ? parent.kind : undefined,
+          isNode(parent) ? parent.kind : undefined,
         ]);
 
         expect(argsStack.pop()).to.deep.equal([...arguments]);

src/language/ast.ts

@@ -125,7 +125,8 @@ export class Token {
  * @internal
  */
 export function isNode(maybeNode: unknown): maybeNode is ASTNode {
-  return maybeNode != null && typeof maybeNode.kind === 'string';
+  // eslint-disable-next-line @typescript-eslint/dot-notation
+  return typeof maybeNode?.['kind'] === 'string';
 }
 
 /**