tests: replace 'invariant' with 'expect' assertion whenever possible

src/execution/__tests__/union-interface-test.js

@@ -1,8 +1,6 @@
 import { expect } from 'chai';
 import { describe, it } from 'mocha';
 
-import { invariant } from '../../jsutils/invariant';
-
 import { parse } from '../../language/parser';
 
 import { GraphQLSchema } from '../../type/schema';
@@ -123,7 +121,7 @@ const PetType = new GraphQLUnionType({
     }
 
     // istanbul ignore next (Not reachable. All possible types have been considered)
-    invariant(false);
+    expect.fail('Not reachable');
   },
 });
 

src/execution/__tests__/variables-test.js

@@ -25,11 +25,11 @@ import { getVariableValues } from '../values';
 const TestComplexScalar = new GraphQLScalarType({
   name: 'ComplexScalar',
   parseValue(value) {
-    invariant(value === 'SerializedValue');
+    expect(value).to.equal('SerializedValue');
     return 'DeserializedValue';
   },
   parseLiteral(ast) {
-    invariant(ast.value === 'SerializedValue');
+    expect(ast).to.include({ kind: 'StringValue', value: 'SerializedValue' });
     return 'DeserializedValue';
   },
 });

src/jsutils/__tests__/inspect-test.js

@@ -2,7 +2,6 @@ import { expect } from 'chai';
 import { describe, it } from 'mocha';
 
 import { inspect } from '../inspect';
-import { invariant } from '../invariant';
 
 describe('inspect', () => {
   it('undefined', () => {
@@ -35,13 +34,13 @@ describe('inspect', () => {
   it('function', () => {
     const unnamedFuncStr = inspect(
       // istanbul ignore next (Never called and used as a placeholder)
-      () => invariant(false),
+      () => expect.fail('Should not be called'),
     );
     expect(unnamedFuncStr).to.equal('[function]');
 
     // istanbul ignore next (Never called and used as a placeholder)
     function namedFunc() {
-      invariant(false);
+      expect.fail('Should not be called');
     }
     expect(inspect(namedFunc)).to.equal('[function namedFunc]');
   });

src/language/__tests__/visitor-test.js

@@ -3,8 +3,6 @@ import { describe, it } from 'mocha';
 
 import { kitchenSinkQuery } from '../../__testUtils__/kitchenSinkQuery';
 
-import { invariant } from '../../jsutils/invariant';
-
 import type { ASTNode } from '../ast';
 import { Kind } from '../kinds';
 import { parse } from '../parser';
@@ -1076,7 +1074,7 @@ describe('Visitor', () => {
             },
             // istanbul ignore next (Never called and used as a placeholder)
             leave() {
-              invariant(false);
+              expect.fail('Should not be called');
             },
           },
           {

src/type/__tests__/introspection-test.js

@@ -1,8 +1,6 @@
 import { expect } from 'chai';
 import { describe, it } from 'mocha';
 
-import { invariant } from '../../jsutils/invariant';
-
 import { buildSchema } from '../../utilities/buildASTSchema';
 import { getIntrospectionQuery } from '../../utilities/getIntrospectionQuery';
 
@@ -1569,12 +1567,12 @@ describe('Introspection', () => {
 
     // istanbul ignore next (Called only to fail test)
     function fieldResolver(_1, _2, _3, info) {
-      invariant(false, `Called on ${info.parentType.name}::${info.fieldName}`);
+      expect.fail(`Called on ${info.parentType.name}::${info.fieldName}`);
     }
 
     // istanbul ignore next (Called only to fail test)
     function typeResolver(_1, _2, info) {
-      invariant(false, `Called on ${info.parentType.name}::${info.fieldName}`);
+      expect.fail(`Called on ${info.parentType.name}::${info.fieldName}`);
     }
 
     const result = graphqlSync({