eslint/tests/lib/rules/no-loop-func.js

   1 /**
   2  * @fileoverview Tests for no-loop-func rule.
   3  * @author Ilya Volodin
   4  */
   5
   6 "use strict";
   7
   8 //------------------------------------------------------------------------------
   9 // Requirements
  10 //------------------------------------------------------------------------------
  11
  12 const rule = require("../../../lib/rules/no-loop-func"),
  13     { RuleTester } = require("../../../lib/rule-tester");
  14
  15 //------------------------------------------------------------------------------
  16 // Tests
  17 //------------------------------------------------------------------------------
  18
  19 const ruleTester = new RuleTester();
  20
  21 ruleTester.run("no-loop-func", rule, {
  22     valid: [
  23         "string = 'function a() {}';",
  24         "for (var i=0; i<l; i++) { } var a = function() { i; };",
  25         "for (var i=0, a=function() { i; }; i<l; i++) { }",
  26         "for (var x in xs.filter(function(x) { return x != upper; })) { }",
  27         {
  28             code: "for (var x of xs.filter(function(x) { return x != upper; })) { }",
  29             parserOptions: { ecmaVersion: 6 }
  30         },
  31
  32         // no refers to variables that declared on upper scope.
  33         "for (var i=0; i<l; i++) { (function() {}) }",
  34         "for (var i in {}) { (function() {}) }",
  35         {
  36             code: "for (var i of {}) { (function() {}) }",
  37             parserOptions: { ecmaVersion: 6 }
  38         },
  39
  40         // functions which are using unmodified variables are OK.
  41         {
  42             code: "for (let i=0; i<l; i++) { (function() { i; }) }",
  43             parserOptions: { ecmaVersion: 6 }
  44         },
  45         {
  46             code: "for (let i in {}) { i = 7; (function() { i; }) }",
  47             parserOptions: { ecmaVersion: 6 }
  48         },
  49         {
  50             code: "for (const i of {}) { (function() { i; }) }",
  51             parserOptions: { ecmaVersion: 6 }
  52         },
  53         {
  54             code: "for (let i = 0; i < 10; ++i) { for (let x in xs.filter(x => x != i)) {  } }",
  55             parserOptions: { ecmaVersion: 6 }
  56         },
  57         {
  58             code: "let a = 0; for (let i=0; i<l; i++) { (function() { a; }); }",
  59             parserOptions: { ecmaVersion: 6 }
  60         },
  61         {
  62             code: "let a = 0; for (let i in {}) { (function() { a; }); }",
  63             parserOptions: { ecmaVersion: 6 }
  64         },
  65         {
  66             code: "let a = 0; for (let i of {}) { (function() { a; }); }",
  67             parserOptions: { ecmaVersion: 6 }
  68         },
  69         {
  70             code: "let a = 0; for (let i=0; i<l; i++) { (function() { (function() { a; }); }); }",
  71             parserOptions: { ecmaVersion: 6 }
  72         },
  73         {
  74             code: "let a = 0; for (let i in {}) { function foo() { (function() { a; }); } }",
  75             parserOptions: { ecmaVersion: 6 }
  76         },
  77         {
  78             code: "let a = 0; for (let i of {}) { (() => { (function() { a; }); }); }",
  79             parserOptions: { ecmaVersion: 6 }
  80         },
  81         {
  82             code: "var a = 0; for (let i=0; i<l; i++) { (function() { a; }); }",
  83             parserOptions: { ecmaVersion: 6 }
  84         },
  85         {
  86             code: "var a = 0; for (let i in {}) { (function() { a; }); }",
  87             parserOptions: { ecmaVersion: 6 }
  88         },
  89         {
  90             code: "var a = 0; for (let i of {}) { (function() { a; }); }",
  91             parserOptions: { ecmaVersion: 6 }
  92         },
  93         {
  94             code: [
  95                 "let result = {};",
  96                 "for (const score in scores) {",
  97                 "  const letters = scores[score];",
  98                 "  letters.split('').forEach(letter => {",
  99                 "    result[letter] = score;",
 100                 "  });",
 101                 "}",
 102                 "result.__default = 6;"
 103             ].join("\n"),
 104             parserOptions: { ecmaVersion: 6 }
 105         },
 106         {
 107             code: [
 108                 "while (true) {",
 109                 "    (function() { a; });",
 110                 "}",
 111                 "let a;"
 112             ].join("\n"),
 113             parserOptions: { ecmaVersion: 6 }
 114         }
 115     ],
 116     invalid: [
 117         {
 118             code: "for (var i=0; i<l; i++) { (function() { i; }) }",
 119             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "FunctionExpression" }]
 120         },
 121         {
 122             code: "for (var i=0; i<l; i++) { for (var j=0; j<m; j++) { (function() { i+j; }) } }",
 123             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i', 'j'" }, type: "FunctionExpression" }]
 124         },
 125         {
 126             code: "for (var i in {}) { (function() { i; }) }",
 127             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "FunctionExpression" }]
 128         },
 129         {
 130             code: "for (var i of {}) { (function() { i; }) }",
 131             parserOptions: { ecmaVersion: 6 },
 132             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "FunctionExpression" }]
 133         },
 134         {
 135             code: "for (var i=0; i < l; i++) { (() => { i; }) }",
 136             parserOptions: { ecmaVersion: 6 },
 137             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "ArrowFunctionExpression" }]
 138         },
 139         {
 140             code: "for (var i=0; i < l; i++) { var a = function() { i; } }",
 141             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "FunctionExpression" }]
 142         },
 143         {
 144             code: "for (var i=0; i < l; i++) { function a() { i; }; a(); }",
 145             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "FunctionDeclaration" }]
 146         },
 147         {
 148             code: "for (var i=0; (function() { i; })(), i<l; i++) { }",
 149             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "FunctionExpression" }]
 150         },
 151         {
 152             code: "for (var i=0; i<l; (function() { i; })(), i++) { }",
 153             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "FunctionExpression" }]
 154         },
 155         {
 156             code: "while(i) { (function() { i; }) }",
 157             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "FunctionExpression" }]
 158         },
 159         {
 160             code: "do { (function() { i; }) } while (i)",
 161             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "FunctionExpression" }]
 162         },
 163
 164         // Warns functions which are using modified variables.
 165         {
 166             code: "let a; for (let i=0; i<l; i++) { a = 1; (function() { a; });}",
 167             parserOptions: { ecmaVersion: 6 },
 168             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "FunctionExpression" }]
 169         },
 170         {
 171             code: "let a; for (let i in {}) { (function() { a; }); a = 1; }",
 172             parserOptions: { ecmaVersion: 6 },
 173             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "FunctionExpression" }]
 174         },
 175         {
 176             code: "let a; for (let i of {}) { (function() { a; }); } a = 1; ",
 177             parserOptions: { ecmaVersion: 6 },
 178             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "FunctionExpression" }]
 179         },
 180         {
 181             code: "let a; for (let i=0; i<l; i++) { (function() { (function() { a; }); }); a = 1; }",
 182             parserOptions: { ecmaVersion: 6 },
 183             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "FunctionExpression" }]
 184         },
 185         {
 186             code: "let a; for (let i in {}) { a = 1; function foo() { (function() { a; }); } }",
 187             parserOptions: { ecmaVersion: 6 },
 188             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "FunctionDeclaration" }]
 189         },
 190         {
 191             code: "let a; for (let i of {}) { (() => { (function() { a; }); }); } a = 1;",
 192             parserOptions: { ecmaVersion: 6 },
 193             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "ArrowFunctionExpression" }]
 194         },
 195         {
 196             code: "for (var i = 0; i < 10; ++i) { for (let x in xs.filter(x => x != i)) {  } }",
 197             parserOptions: { ecmaVersion: 6 },
 198             errors: [{ messageId: "unsafeRefs", data: { varNames: "'i'" }, type: "ArrowFunctionExpression" }]
 199         },
 200         {
 201             code: "for (let x of xs) { let a; for (let y of ys) { a = 1; (function() { a; }); } }",
 202             parserOptions: { ecmaVersion: 6 },
 203             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "FunctionExpression" }]
 204         },
 205         {
 206             code: "for (var x of xs) { for (let y of ys) { (function() { x; }); } }",
 207             parserOptions: { ecmaVersion: 6 },
 208             errors: [{ messageId: "unsafeRefs", data: { varNames: "'x'" }, type: "FunctionExpression" }]
 209         },
 210         {
 211             code: "for (var x of xs) { (function() { x; }); }",
 212             parserOptions: { ecmaVersion: 6 },
 213             errors: [{ messageId: "unsafeRefs", data: { varNames: "'x'" }, type: "FunctionExpression" }]
 214         },
 215         {
 216             code: "var a; for (let x of xs) { a = 1; (function() { a; }); }",
 217             parserOptions: { ecmaVersion: 6 },
 218             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "FunctionExpression" }]
 219         },
 220         {
 221             code: "var a; for (let x of xs) { (function() { a; }); a = 1; }",
 222             parserOptions: { ecmaVersion: 6 },
 223             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "FunctionExpression" }]
 224         },
 225         {
 226             code: "let a; function foo() { a = 10; } for (let x of xs) { (function() { a; }); } foo();",
 227             parserOptions: { ecmaVersion: 6 },
 228             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "FunctionExpression" }]
 229         },
 230         {
 231             code: "let a; function foo() { a = 10; for (let x of xs) { (function() { a; }); } } foo();",
 232             parserOptions: { ecmaVersion: 6 },
 233             errors: [{ messageId: "unsafeRefs", data: { varNames: "'a'" }, type: "FunctionExpression" }]
 234         }
 235     ]
 236 });