Docs: examples with arrow functions in no-return-assign (fixes #13135) (#13138)

* Chore: docs example for arrow function and tests (fixes #13135) * Chore: removed wrong test case * Chore: refactore snipper and added tests

Author: anikethsaha

docs/rules/no-return-assign.md

@@ -40,6 +40,14 @@ function doSomething() {
 function doSomething() {
  return foo += 2;
 }
+
+const foo = (a, b) => a = b
+
+const bar = (a, b, c) => (a = b, c == b)
+
+function doSomething() {
+ return foo = bar && foo > 0;
+}
 ```
 
 Examples of **correct** code for the default `"except-parens"` option:
@@ -58,6 +66,14 @@ function doSomething() {
 function doSomething() {
  return (foo = bar + 2);
 }
+
+const foo = (a, b) => (a = b)
+
+const bar = (a, b, c) => ((a = b), c == b)
+
+function doSomething() {
+ return (foo = bar) && foo > 0;
+}
 ```
 
 ### always

tests/lib/rules/no-return-assign.js

@@ -52,6 +52,19 @@ ruleTester.run("no-return-assign", rule, {
  {
  code: "() => (result = a * b)",
  options: ["except-parens"]
+ },
+ "const foo = (a,b,c) => ((a = b), c)",
+ `function foo(){
+ return (a = b)
+ }`,
+ `function bar(){
+ return function foo(){
+ return (a = b) && c
+ }
+ }`,
+ {
+ code: "const foo = (a) => (b) => (a = b)",
+ parserOptions: { ecmaVersion: 6 }
  }
  ],
  invalid: [
@@ -79,7 +92,12 @@ ruleTester.run("no-return-assign", rule, {
  },
  {
  code: "() => result = a * b",
- errors: [{ messageId: "arrowAssignment", type: "ArrowFunctionExpression" }]
+ errors: [
+ {
+ messageId: "arrowAssignment",
+ type: "ArrowFunctionExpression"
+ }
+ ]
  },
  {
  code: "function x() { return result = a * b; };",
@@ -95,6 +113,68 @@ ruleTester.run("no-return-assign", rule, {
  code: "function x() { return result || (result = a * b); };",
  options: ["always"],
  errors: [{ messageId: "returnAssignment", type: "ReturnStatement" }]
+ },
+ {
+ code: `function foo(){
+ return a = b
+ }`,
+ errors: [{ messageId: "returnAssignment", type: "ReturnStatement" }]
+ },
+ {
+ code: `function doSomething() {
+ return foo = bar && foo > 0;
+ }`,
+ errors: [{ messageId: "returnAssignment", type: "ReturnStatement" }]
+ },
+ {
+ code: `function doSomething() {
+ return foo = function(){
+ return (bar = bar1)
+ }
+ }`,
+ errors: [{ messageId: "returnAssignment", type: "ReturnStatement" }]
+ },
+ {
+ code: `function doSomething() {
+ return foo = () => a
+ }`,
+ parserOptions: { ecmaVersion: 6 },
+ errors: [
+ {
+ messageId: "returnAssignment",
+ type: "ReturnStatement"
+ }
+ ]
+ },
+ {
+ code: `function doSomething() {
+ return () => a = () => b
+ }`,
+ parserOptions: { ecmaVersion: 6 },
+ errors: [
+ {
+ messageId: "arrowAssignment",
+ type: "ArrowFunctionExpression"
+ }
+ ]
+ },
+ {
+ code: `function foo(a){
+ return function bar(b){
+ return a = b
+ }
+ }`,
+ errors: [{ messageId: "returnAssignment", type: "ReturnStatement" }]
+ },
+ {
+ code: "const foo = (a) => (b) => a = b",
+ parserOptions: { ecmaVersion: 6 },
+ errors: [
+ {
+ messageId: "arrowAssignment",
+ type: "ArrowFunctionExpression"
+ }
+ ]
  }
  ]
 });