eslint/tests/lib/rules/init-declarations.js

   1 /**
   2  * @fileoverview A rule to control the style of variable initializations.
   3  * @author Colin Ihrig
   4  */
   5
   6 "use strict";
   7
   8 //------------------------------------------------------------------------------
   9 // Requirements
  10 //------------------------------------------------------------------------------
  11
  12 const rule = require("../../../lib/rules/init-declarations"),
  13     { RuleTester } = require("../../../lib/rule-tester");
  14
  15 const ruleTester = new RuleTester();
  16
  17 ruleTester.run("init-declarations", rule, {
  18     valid: [
  19         "var foo = null;",
  20         "foo = true;",
  21         "var foo = 1, bar = false, baz = {};",
  22         "function foo() { var foo = 0; var bar = []; }",
  23         "var fn = function() {};",
  24         "var foo = bar = 2;",
  25         "for (var i = 0; i < 1; i++) {}",
  26         "for (var foo in []) {}",
  27         { code: "for (var foo of []) {}", parserOptions: { ecmaVersion: 6 } },
  28         {
  29             code: "let a = true;",
  30             options: ["always"],
  31             parserOptions: { ecmaVersion: 6 }
  32         },
  33         {
  34             code: "const a = {};",
  35             options: ["always"],
  36             parserOptions: { ecmaVersion: 6 }
  37         },
  38         {
  39             code: "function foo() { let a = 1, b = false; if (a) { let c = 3, d = null; } }",
  40             options: ["always"],
  41             parserOptions: { ecmaVersion: 6 }
  42         },
  43         {
  44             code: "function foo() { const a = 1, b = true; if (a) { const c = 3, d = null; } }",
  45             options: ["always"],
  46             parserOptions: { ecmaVersion: 6 }
  47         },
  48         {
  49             code: "function foo() { let a = 1; const b = false; var c = true; }",
  50             options: ["always"],
  51             parserOptions: { ecmaVersion: 6 }
  52         },
  53         {
  54             code: "var foo;",
  55             options: ["never"],
  56             parserOptions: { ecmaVersion: 6 }
  57         },
  58         {
  59             code: "var foo, bar, baz;",
  60             options: ["never"],
  61             parserOptions: { ecmaVersion: 6 }
  62         },
  63         {
  64             code: "function foo() { var foo; var bar; }",
  65             options: ["never"],
  66             parserOptions: { ecmaVersion: 6 }
  67         },
  68         {
  69             code: "let a;",
  70             options: ["never"],
  71             parserOptions: { ecmaVersion: 6 }
  72         },
  73         {
  74             code: "const a = 1;",
  75             options: ["never"],
  76             parserOptions: { ecmaVersion: 6 }
  77         },
  78         {
  79             code: "function foo() { let a, b; if (a) { let c, d; } }",
  80             options: ["never"],
  81             parserOptions: { ecmaVersion: 6 }
  82         },
  83         {
  84             code: "function foo() { const a = 1, b = true; if (a) { const c = 3, d = null; } }",
  85             options: ["never"],
  86             parserOptions: { ecmaVersion: 6 }
  87         },
  88         {
  89             code: "function foo() { let a; const b = false; var c; }",
  90             options: ["never"],
  91             parserOptions: { ecmaVersion: 6 }
  92         },
  93         {
  94             code: "for(var i = 0; i < 1; i++){}",
  95             options: ["never", { ignoreForLoopInit: true }]
  96         },
  97         {
  98             code: "for (var foo in []) {}",
  99             options: ["never", { ignoreForLoopInit: true }]
 100         },
 101         {
 102             code: "for (var foo of []) {}",
 103             options: ["never", { ignoreForLoopInit: true }],
 104             parserOptions: { ecmaVersion: 6 }
 105         }
 106     ],
 107     invalid: [
 108         {
 109             code: "var foo;",
 110             options: ["always"],
 111             errors: [
 112                 {
 113                     messageId: "initialized",
 114                     data: { idName: "foo" },
 115                     type: "VariableDeclarator"
 116                 }
 117             ]
 118         },
 119         {
 120             code: "for (var a in []) var foo;",
 121             options: ["always"],
 122             errors: [
 123                 {
 124                     messageId: "initialized",
 125                     data: { idName: "foo" },
 126                     type: "VariableDeclarator"
 127                 }
 128             ]
 129         },
 130         {
 131             code: "var foo, bar = false, baz;",
 132             options: ["always"],
 133             parserOptions: { ecmaVersion: 6 },
 134             errors: [
 135                 {
 136                     messageId: "initialized",
 137                     data: { idName: "foo" },
 138                     type: "VariableDeclarator"
 139                 },
 140                 {
 141                     messageId: "initialized",
 142                     data: { idName: "baz" },
 143                     type: "VariableDeclarator"
 144                 }
 145             ]
 146         },
 147         {
 148             code: "function foo() { var foo = 0; var bar; }",
 149             options: ["always"],
 150             parserOptions: { ecmaVersion: 6 },
 151             errors: [
 152                 {
 153                     messageId: "initialized",
 154                     data: { idName: "bar" },
 155                     type: "VariableDeclarator"
 156                 }
 157             ]
 158         },
 159         {
 160             code: "function foo() { var foo; var bar = foo; }",
 161             options: ["always"],
 162             parserOptions: { ecmaVersion: 6 },
 163             errors: [
 164                 {
 165                     messageId: "initialized",
 166                     data: { idName: "foo" },
 167                     type: "VariableDeclarator"
 168                 }
 169             ]
 170         },
 171         {
 172             code: "let a;",
 173             options: ["always"],
 174             parserOptions: { ecmaVersion: 6 },
 175             errors: [
 176                 {
 177                     messageId: "initialized",
 178                     data: { idName: "a" },
 179                     type: "VariableDeclarator"
 180                 }
 181             ]
 182         },
 183         {
 184             code: "function foo() { let a = 1, b; if (a) { let c = 3, d = null; } }",
 185             options: ["always"],
 186             parserOptions: { ecmaVersion: 6 },
 187             errors: [
 188                 {
 189                     messageId: "initialized",
 190                     data: { idName: "b" },
 191                     type: "VariableDeclarator"
 192                 }
 193             ]
 194         },
 195         {
 196             code: "function foo() { let a; const b = false; var c; }",
 197             options: ["always"],
 198             parserOptions: { ecmaVersion: 6 },
 199             errors: [
 200                 {
 201                     messageId: "initialized",
 202                     data: { idName: "a" },
 203                     type: "VariableDeclarator"
 204                 },
 205                 {
 206                     messageId: "initialized",
 207                     data: { idName: "c" },
 208                     type: "VariableDeclarator"
 209                 }
 210             ]
 211         },
 212         {
 213             code: "var foo = bar = 2;",
 214             options: ["never"],
 215             parserOptions: { ecmaVersion: 6 },
 216             errors: [
 217                 {
 218                     messageId: "notInitialized",
 219                     data: { idName: "foo" },
 220                     type: "VariableDeclarator"
 221                 }
 222             ]
 223         },
 224         {
 225             code: "var foo = true;",
 226             options: ["never"],
 227             parserOptions: { ecmaVersion: 6 },
 228             errors: [
 229                 {
 230                     messageId: "notInitialized",
 231                     data: { idName: "foo" },
 232                     type: "VariableDeclarator"
 233                 }
 234             ]
 235         },
 236         {
 237             code: "var foo, bar = 5, baz = 3;",
 238             options: ["never"],
 239             parserOptions: { ecmaVersion: 6 },
 240             errors: [
 241                 {
 242                     messageId: "notInitialized",
 243                     data: { idName: "bar" },
 244                     type: "VariableDeclarator"
 245                 },
 246                 {
 247                     messageId: "notInitialized",
 248                     data: { idName: "baz" },
 249                     type: "VariableDeclarator"
 250                 }
 251             ]
 252         },
 253         {
 254             code: "function foo() { var foo; var bar = foo; }",
 255             options: ["never"],
 256             parserOptions: { ecmaVersion: 6 },
 257             errors: [
 258                 {
 259                     messageId: "notInitialized",
 260                     data: { idName: "bar" },
 261
 262                     type: "VariableDeclarator"
 263                 }
 264             ]
 265         },
 266         {
 267             code: "let a = 1;",
 268             options: ["never"],
 269             parserOptions: { ecmaVersion: 6 },
 270             errors: [
 271                 {
 272                     messageId: "notInitialized",
 273                     data: { idName: "a" },
 274                     type: "VariableDeclarator"
 275                 }
 276             ]
 277         },
 278         {
 279             code: "function foo() { let a = 'foo', b; if (a) { let c, d; } }",
 280             options: ["never"],
 281             parserOptions: { ecmaVersion: 6 },
 282             errors: [
 283                 {
 284                     messageId: "notInitialized",
 285                     data: { idName: "a" },
 286                     type: "VariableDeclarator"
 287                 }
 288             ]
 289         },
 290         {
 291             code: "function foo() { let a; const b = false; var c = 1; }",
 292             options: ["never"],
 293             parserOptions: { ecmaVersion: 6 },
 294             errors: [
 295                 {
 296                     messageId: "notInitialized",
 297                     data: { idName: "c" },
 298                     type: "VariableDeclarator"
 299                 }
 300             ]
 301         },
 302         {
 303             code: "for(var i = 0; i < 1; i++){}",
 304             options: ["never"],
 305             errors: [
 306                 {
 307                     messageId: "notInitialized",
 308                     data: { idName: "i" },
 309                     type: "VariableDeclarator"
 310                 }
 311             ]
 312         },
 313         {
 314             code: "for (var foo in []) {}",
 315             options: ["never"],
 316             errors: [
 317                 {
 318                     messageId: "notInitialized",
 319                     data: { idName: "foo" },
 320                     type: "VariableDeclarator"
 321                 }
 322             ]
 323         },
 324         {
 325             code: "for (var foo of []) {}",
 326             options: ["never"],
 327             parserOptions: { ecmaVersion: 6 },
 328             errors: [
 329                 {
 330                     messageId: "notInitialized",
 331                     data: { idName: "foo" },
 332                     type: "VariableDeclarator"
 333                 }
 334             ]
 335         }
 336     ]
 337 });