[Fix] display-name: fix false positive for HOF returning only nulls and literals

Author: chiawendt

lib/util/Components.js

@@ -503,7 +503,6 @@ function componentRule(rule, context) {
  if (
  (node.parent.type === 'ReturnStatement' || (node.parent.type === 'ArrowFunctionExpression' && node.parent.expression))
  && !utils.isReturningJSX(node)
- && !utils.isReturningOnlyNull(node)
  ) {
  return undefined;
  }

tests/lib/rules/display-name.js

@@ -556,6 +556,17 @@ ruleTester.run('display-name', rule, {
  }
  `,
  },
+ {
+ // issue #3300
+ code: `
+ const f = (a) => () => {
+ if (a) {
+ return null;
+ }
+ return 1;
+ };
+ `,
+ },
  {
  code: `
  class Test {
@@ -1169,33 +1180,5 @@ ruleTester.run('display-name', rule, {
  },
  ],
  },
- {
- code: `
- Demo = () => () => null;
- `,
- errors: [{ messageId: 'noDisplayName' }],
- },
- {
- code: `
- demo = {
- Property: () => () => null
- }
- `,
- errors: [{ messageId: 'noDisplayName' }],
- },
- {
- code: `
- Demo = function() {return function() {return null;};};
- `,
- errors: [{ messageId: 'noDisplayName' }],
- },
- {
- code: `
- demo = {
- Property: function() {return function() {return null;};}
- }
- `,
- errors: [{ messageId: 'noDisplayName' }],
- },
  ]),
 });

tests/lib/rules/no-this-in-sfc.js

@@ -275,58 +275,5 @@ ruleTester.run('no-this-in-sfc', rule, {
  { messageId: 'noThisInSFC' },
  ],
  },
- {
- code: `
- class Foo {
- bar() {
- return () => {
- this.something();
- return null;
- }
- }
- }
- `,
- errors: [{ messageId: 'noThisInSFC' }],
- },
- {
- code: `
- class Foo {
- bar = () => () => {
- this.something();
- return null;
- };
- }
- `,
- features: ['class fields', 'no-ts-old'], // TODO: FIXME: remove `no-ts-old` and fix
- errors: [{ messageId: 'noThisInSFC' }],
- },
- {
- code: `
- class Foo {
- bar() {
- function Bar(){
- return () => {
- this.something();
- return null;
- }
- }
- }
- }
- `,
- errors: [{ messageId: 'noThisInSFC' }],
- },
- {
- code: `
- class Foo {
- bar() {
- () => () => {
- this.something();
- return null;
- };
- }
- }
- `,
- errors: [{ messageId: 'noThisInSFC' }],
- },
  ]),
 });