eslint/tests/lib/rules/no-redeclare.js

   1 /**
   2  * @fileoverview Tests for no-redeclare rule.
   3  * @author Ilya Volodin
   4  */
   5
   6 "use strict";
   7
   8 //------------------------------------------------------------------------------
   9 // Requirements
  10 //------------------------------------------------------------------------------
  11
  12 const rule = require("../../../lib/rules/no-redeclare");
  13 const { RuleTester } = require("../../../lib/rule-tester");
  14
  15 //------------------------------------------------------------------------------
  16 // Tests
  17 //------------------------------------------------------------------------------
  18
  19 const ruleTester = new RuleTester();
  20
  21 ruleTester.run("no-redeclare", rule, {
  22     valid: [
  23         "var a = 3; var b = function() { var a = 10; };",
  24         "var a = 3; a = 10;",
  25         {
  26             code: "if (true) {\n    let b = 2;\n} else {    \nlet b = 3;\n}",
  27             parserOptions: {
  28                 ecmaVersion: 6
  29             }
  30         },
  31         { code: "var Object = 0;", options: [{ builtinGlobals: false }] },
  32         { code: "var Object = 0;", options: [{ builtinGlobals: true }], parserOptions: { ecmaVersion: 6, sourceType: "module" } },
  33         { code: "var Object = 0;", options: [{ builtinGlobals: true }], parserOptions: { ecmaFeatures: { globalReturn: true } } },
  34         { code: "var top = 0;", options: [{ builtinGlobals: true }] },
  35         { code: "var top = 0;", options: [{ builtinGlobals: true }], parserOptions: { ecmaFeatures: { globalReturn: true } }, env: { browser: true } },
  36         { code: "var top = 0;", options: [{ builtinGlobals: true }], parserOptions: { ecmaVersion: 6, sourceType: "module" }, env: { browser: true } },
  37         {
  38             code: "var self = 1",
  39             options: [{ builtinGlobals: true }],
  40             env: { browser: false }
  41         },
  42         { code: "var glovalThis = foo", options: [{ builtinGlobals: true }], env: { es6: true } },
  43         { code: "var glovalThis = foo", options: [{ builtinGlobals: true }], env: { es2017: true } },
  44
  45         // Comments and built-ins.
  46         {
  47             code: "/*globals Array */",
  48             options: [{ builtinGlobals: false }]
  49         },
  50         {
  51             code: "/*globals a */",
  52             options: [{ builtinGlobals: false }],
  53             globals: { a: "readonly" }
  54         },
  55         {
  56             code: "/*globals a */",
  57             options: [{ builtinGlobals: false }],
  58             globals: { a: "writable" }
  59         },
  60         {
  61             code: "/*globals a:off */",
  62             options: [{ builtinGlobals: true }],
  63             globals: { a: "readonly" }
  64         },
  65         {
  66             code: "/*globals a */",
  67             options: [{ builtinGlobals: true }],
  68             globals: { a: "off" }
  69         }
  70     ],
  71     invalid: [
  72         { code: "var a = 3; var a = 10;", parserOptions: { ecmaVersion: 6 }, errors: [{ message: "'a' is already defined.", type: "Identifier" }] },
  73         { code: "switch(foo) { case a: var b = 3;\ncase b: var b = 4}", errors: [{ message: "'b' is already defined.", type: "Identifier" }] },
  74         { code: "var a = 3; var a = 10;", errors: [{ message: "'a' is already defined.", type: "Identifier" }] },
  75         { code: "var a = {}; var a = [];", errors: [{ message: "'a' is already defined.", type: "Identifier" }] },
  76         { code: "var a; function a() {}", errors: [{ message: "'a' is already defined.", type: "Identifier" }] },
  77         { code: "function a() {} function a() {}", errors: [{ message: "'a' is already defined.", type: "Identifier" }] },
  78         { code: "var a = function() { }; var a = function() { }", errors: [{ message: "'a' is already defined.", type: "Identifier" }] },
  79         { code: "var a = function() { }; var a = new Date();", errors: [{ message: "'a' is already defined.", type: "Identifier" }] },
  80         { code: "var a = 3; var a = 10; var a = 15;", errors: [{ message: "'a' is already defined.", type: "Identifier" }, { message: "'a' is already defined.", type: "Identifier" }] },
  81         { code: "var a; var a;", parserOptions: { ecmaVersion: 6, sourceType: "module" }, errors: [{ message: "'a' is already defined.", type: "Identifier" }] },
  82         { code: "export var a; var a;", parserOptions: { ecmaVersion: 6, sourceType: "module" }, errors: [{ message: "'a' is already defined.", type: "Identifier" }] },
  83         {
  84             code: "var Object = 0;",
  85             options: [{ builtinGlobals: true }],
  86             errors: [{ message: "'Object' is already defined as a built-in global variable.", type: "Identifier" }]
  87         },
  88         {
  89             code: "var top = 0;",
  90             options: [{ builtinGlobals: true }],
  91             env: { browser: true },
  92             errors: [{ message: "'top' is already defined as a built-in global variable.", type: "Identifier" }]
  93         },
  94         {
  95             code: "var a; var {a = 0, b: Object = 0} = {};",
  96             options: [{ builtinGlobals: true }],
  97             parserOptions: { ecmaVersion: 6 },
  98             errors: [
  99                 { message: "'a' is already defined.", type: "Identifier" },
 100                 { message: "'Object' is already defined as a built-in global variable.", type: "Identifier" }
 101             ]
 102         },
 103         {
 104             code: "var a; var {a = 0, b: Object = 0} = {};",
 105             options: [{ builtinGlobals: true }],
 106             parserOptions: { ecmaVersion: 6, sourceType: "module" },
 107             errors: [
 108                 { message: "'a' is already defined.", type: "Identifier" }
 109             ]
 110         },
 111         {
 112             code: "var a; var {a = 0, b: Object = 0} = {};",
 113             options: [{ builtinGlobals: true }],
 114             parserOptions: { ecmaVersion: 6, ecmaFeatures: { globalReturn: true } },
 115             errors: [
 116                 { message: "'a' is already defined.", type: "Identifier" }
 117             ]
 118         },
 119         {
 120             code: "var a; var {a = 0, b: Object = 0} = {};",
 121             options: [{ builtinGlobals: false }],
 122             parserOptions: { ecmaVersion: 6 },
 123             errors: [
 124                 { message: "'a' is already defined.", type: "Identifier" }
 125             ]
 126         },
 127         {
 128             code: "var globalThis = 0;",
 129             options: [{ builtinGlobals: true }],
 130             env: { es2020: true },
 131             errors: [{ message: "'globalThis' is already defined as a built-in global variable.", type: "Identifier" }]
 132         },
 133         {
 134             code: "var a; var {a = 0, b: globalThis = 0} = {};",
 135             options: [{ builtinGlobals: true }],
 136             parserOptions: { ecmaVersion: 6 },
 137             env: { es2020: true },
 138             errors: [
 139                 { message: "'a' is already defined.", type: "Identifier" },
 140                 { message: "'globalThis' is already defined as a built-in global variable.", type: "Identifier" }
 141             ]
 142         },
 143         {
 144             code: "/*global b:false*/ var b = 1;",
 145             options: [{ builtinGlobals: true }],
 146             errors: [{
 147                 message: "'b' is already defined by a variable declaration.",
 148                 type: "Block",
 149                 line: 1,
 150                 column: 10,
 151                 endLine: 1,
 152                 endColumn: 11
 153             }]
 154         },
 155         {
 156             code: "/*global b:true*/ var b = 1;",
 157             options: [{ builtinGlobals: true }],
 158             errors: [{
 159                 message: "'b' is already defined by a variable declaration.",
 160                 type: "Block",
 161                 line: 1,
 162                 column: 10,
 163                 endLine: 1,
 164                 endColumn: 11
 165             }]
 166         },
 167         {
 168             code: "function f() { var a; var a; }",
 169             errors: [
 170                 { message: "'a' is already defined.", type: "Identifier" }
 171             ]
 172         },
 173         {
 174             code: "function f(a) { var a; }",
 175             errors: [
 176                 { message: "'a' is already defined.", type: "Identifier" }
 177             ]
 178         },
 179         {
 180             code: "function f() { var a; if (test) { var a; } }",
 181             errors: [
 182                 { message: "'a' is already defined.", type: "Identifier" }
 183             ]
 184         },
 185         {
 186             code: "for (var a, a;;);",
 187             errors: [
 188                 { message: "'a' is already defined.", type: "Identifier" }
 189             ]
 190         },
 191
 192         {
 193             code: "var Object = 0;",
 194             errors: [
 195                 { message: "'Object' is already defined as a built-in global variable.", type: "Identifier" }
 196             ]
 197         },
 198         {
 199             code: "var top = 0;",
 200             env: { browser: true },
 201             errors: [
 202                 { message: "'top' is already defined as a built-in global variable.", type: "Identifier" }
 203             ]
 204         },
 205
 206         // Comments and built-ins.
 207         {
 208             code: "/*globals Array */",
 209             options: [{ builtinGlobals: true }],
 210             errors: [{
 211                 message: "'Array' is already defined as a built-in global variable.",
 212                 type: "Block",
 213                 line: 1,
 214                 column: 11,
 215                 endLine: 1,
 216                 endColumn: 16
 217             }]
 218         },
 219         {
 220             code: "/*globals parseInt */",
 221             options: [{ builtinGlobals: true }],
 222             errors: [{
 223                 message: "'parseInt' is already defined as a built-in global variable.",
 224                 type: "Block",
 225                 line: 1,
 226                 column: 11,
 227                 endLine: 1,
 228                 endColumn: 19
 229             }]
 230         },
 231         {
 232             code: "/*globals foo, Array */",
 233             options: [{ builtinGlobals: true }],
 234             errors: [{
 235                 message: "'Array' is already defined as a built-in global variable.",
 236                 type: "Block",
 237                 line: 1,
 238                 column: 16,
 239                 endLine: 1,
 240                 endColumn: 21
 241             }]
 242         },
 243         {
 244             code: "/* globals foo, Array, baz */",
 245             options: [{ builtinGlobals: true }],
 246             errors: [{
 247                 message: "'Array' is already defined as a built-in global variable.",
 248                 type: "Block",
 249                 line: 1,
 250                 column: 17,
 251                 endLine: 1,
 252                 endColumn: 22
 253             }]
 254         },
 255         {
 256             code: "/*global foo, Array, baz*/",
 257             options: [{ builtinGlobals: true }],
 258             errors: [{
 259                 message: "'Array' is already defined as a built-in global variable.",
 260                 type: "Block",
 261                 line: 1,
 262                 column: 15,
 263                 endLine: 1,
 264                 endColumn: 20
 265             }]
 266         },
 267         {
 268             code: "/*global array, Array*/",
 269             options: [{ builtinGlobals: true }],
 270             errors: [{
 271                 message: "'Array' is already defined as a built-in global variable.",
 272                 type: "Block",
 273                 line: 1,
 274                 column: 17,
 275                 endLine: 1,
 276                 endColumn: 22
 277             }]
 278         },
 279         {
 280             code: "/*globals a,Array*/",
 281             options: [{ builtinGlobals: true }],
 282             errors: [{
 283                 message: "'Array' is already defined as a built-in global variable.",
 284                 type: "Block",
 285                 line: 1,
 286                 column: 13,
 287                 endLine: 1,
 288                 endColumn: 18
 289             }]
 290         },
 291         {
 292             code: "/*globals a:readonly, Array:writable */",
 293             options: [{ builtinGlobals: true }],
 294             errors: [{
 295                 message: "'Array' is already defined as a built-in global variable.",
 296                 type: "Block",
 297                 line: 1,
 298                 column: 23,
 299                 endLine: 1,
 300                 endColumn: 28
 301             }]
 302         },
 303         {
 304             code: "\n/*globals Array */",
 305             options: [{ builtinGlobals: true }],
 306             errors: [{
 307                 message: "'Array' is already defined as a built-in global variable.",
 308                 type: "Block",
 309                 line: 2,
 310                 column: 11,
 311                 endLine: 2,
 312                 endColumn: 16
 313             }]
 314         },
 315         {
 316             code: "/*globals\nArray */",
 317             options: [{ builtinGlobals: true }],
 318             errors: [{
 319                 message: "'Array' is already defined as a built-in global variable.",
 320                 type: "Block",
 321                 line: 2,
 322                 column: 1,
 323                 endLine: 2,
 324                 endColumn: 6
 325             }]
 326         },
 327         {
 328             code: "\n/*globals\n\nArray*/",
 329             options: [{ builtinGlobals: true }],
 330             errors: [{
 331                 message: "'Array' is already defined as a built-in global variable.",
 332                 type: "Block",
 333                 line: 4,
 334                 column: 1,
 335                 endLine: 4,
 336                 endColumn: 6
 337             }]
 338         },
 339         {
 340             code: "/*globals foo,\n    Array */",
 341             options: [{ builtinGlobals: true }],
 342             errors: [{
 343                 message: "'Array' is already defined as a built-in global variable.",
 344                 type: "Block",
 345                 line: 2,
 346                 column: 5,
 347                 endLine: 2,
 348                 endColumn: 10
 349             }]
 350         },
 351         {
 352             code: "/*globals a */",
 353             options: [{ builtinGlobals: true }],
 354             globals: { a: "readonly" },
 355             errors: [{
 356                 message: "'a' is already defined as a built-in global variable.",
 357                 type: "Block",
 358                 line: 1,
 359                 column: 11,
 360                 endLine: 1,
 361                 endColumn: 12
 362             }]
 363         },
 364         {
 365             code: "/*globals a */",
 366             options: [{ builtinGlobals: true }],
 367             globals: { a: "writable" },
 368             errors: [{
 369                 message: "'a' is already defined as a built-in global variable.",
 370                 type: "Block",
 371                 line: 1,
 372                 column: 11,
 373                 endLine: 1,
 374                 endColumn: 12
 375             }]
 376         },
 377         {
 378             code: "/*globals a */ /*globals a */",
 379             errors: [{
 380                 message: "'a' is already defined.",
 381                 type: "Block",
 382                 line: 1,
 383                 column: 26,
 384                 endLine: 1,
 385                 endColumn: 27
 386             }]
 387         },
 388         {
 389             code: "/*globals a */ /*globals a */ var a = 0",
 390             options: [{ builtinGlobals: true }],
 391             globals: { a: "writable" },
 392             errors: [
 393                 {
 394                     message: "'a' is already defined as a built-in global variable.",
 395                     type: "Block",
 396                     line: 1,
 397                     column: 11,
 398                     endLine: 1,
 399                     endColumn: 12
 400                 },
 401                 {
 402                     message: "'a' is already defined as a built-in global variable.",
 403                     type: "Block",
 404                     line: 1,
 405                     column: 26,
 406                     endLine: 1,
 407                     endColumn: 27
 408                 },
 409                 {
 410                     message: "'a' is already defined as a built-in global variable.",
 411                     type: "Identifier",
 412                     line: 1,
 413                     column: 35,
 414                     endLine: 1,
 415                     endColumn: 36
 416                 }
 417             ]
 418         }
 419     ]
 420 });