eslint/tests/lib/rules/vars-on-top.js

   1 /**
   2  * @fileoverview Tests for vars-on-top rule.
   3  * @author Danny Fritz
   4  * @author Gyandeep Singh
   5  */
   6 "use strict";
   7
   8 //------------------------------------------------------------------------------
   9 // Requirements
  10 //------------------------------------------------------------------------------
  11
  12 const rule = require("../../../lib/rules/vars-on-top"),
  13     { RuleTester } = require("../../../lib/rule-tester");
  14
  15 //------------------------------------------------------------------------------
  16 // Tests
  17 //------------------------------------------------------------------------------
  18
  19 const ruleTester = new RuleTester();
  20 const error = { messageId: "top", type: "VariableDeclaration" };
  21
  22 ruleTester.run("vars-on-top", rule, {
  23
  24     valid: [
  25         [
  26             "var first = 0;",
  27             "function foo() {",
  28             "    first = 2;",
  29             "}"
  30         ].join("\n"),
  31         [
  32             "function foo() {",
  33             "}"
  34         ].join("\n"),
  35         [
  36             "function foo() {",
  37             "   var first;",
  38             "   if (true) {",
  39             "       first = true;",
  40             "   } else {",
  41             "       first = 1;",
  42             "   }",
  43             "}"
  44         ].join("\n"),
  45         [
  46             "function foo() {",
  47             "   var first;",
  48             "   var second = 1;",
  49             "   var third;",
  50             "   var fourth = 1, fifth, sixth = third;",
  51             "   var seventh;",
  52             "   if (true) {",
  53             "       third = true;",
  54             "   }",
  55             "   first = second;",
  56             "}"
  57         ].join("\n"),
  58         [
  59             "function foo() {",
  60             "   var i;",
  61             "   for (i = 0; i < 10; i++) {",
  62             "       alert(i);",
  63             "   }",
  64             "}"
  65         ].join("\n"),
  66         [
  67             "function foo() {",
  68             "   var outer;",
  69             "   function inner() {",
  70             "       var inner = 1;",
  71             "       var outer = inner;",
  72             "   }",
  73             "   outer = 1;",
  74             "}"
  75         ].join("\n"),
  76         [
  77             "function foo() {",
  78             "   var first;",
  79             "   //Hello",
  80             "   var second = 1;",
  81             "   first = second;",
  82             "}"
  83         ].join("\n"),
  84         [
  85             "function foo() {",
  86             "   var first;",
  87             "   /*",
  88             "       Hello Clarice",
  89             "   */",
  90             "   var second = 1;",
  91             "   first = second;",
  92             "}"
  93         ].join("\n"),
  94         [
  95             "function foo() {",
  96             "   var first;",
  97             "   var second = 1;",
  98             "   function bar(){",
  99             "       var first;",
 100             "       first = 5;",
 101             "   }",
 102             "   first = second;",
 103             "}"
 104         ].join("\n"),
 105         [
 106             "function foo() {",
 107             "   var first;",
 108             "   var second = 1;",
 109             "   function bar(){",
 110             "       var third;",
 111             "       third = 5;",
 112             "   }",
 113             "   first = second;",
 114             "}"
 115         ].join("\n"),
 116         [
 117             "function foo() {",
 118             "   var first;",
 119             "   var bar = function(){",
 120             "       var third;",
 121             "       third = 5;",
 122             "   }",
 123             "   first = 5;",
 124             "}"
 125         ].join("\n"),
 126         [
 127             "function foo() {",
 128             "   var first;",
 129             "   first.onclick(function(){",
 130             "       var third;",
 131             "       third = 5;",
 132             "   });",
 133             "   first = 5;",
 134             "}"
 135         ].join("\n"),
 136         {
 137             code: [
 138                 "function foo() {",
 139                 "   var i = 0;",
 140                 "   for (let j = 0; j < 10; j++) {",
 141                 "       alert(j);",
 142                 "   }",
 143                 "   i = i + 1;",
 144                 "}"
 145             ].join("\n"),
 146             parserOptions: {
 147                 ecmaVersion: 6
 148             }
 149         },
 150         "'use strict'; var x; f();",
 151         "'use strict'; 'directive'; var x; var y; f();",
 152         "function f() { 'use strict'; var x; f(); }",
 153         "function f() { 'use strict'; 'directive'; var x; var y; f(); }",
 154         { code: "import React from 'react'; var y; function f() { 'use strict'; var x; var y; f(); }", parserOptions: { ecmaVersion: 6, sourceType: "module" } },
 155         { code: "'use strict'; import React from 'react'; var y; function f() { 'use strict'; var x; var y; f(); }", parserOptions: { ecmaVersion: 6, sourceType: "module" } },
 156         { code: "import React from 'react'; 'use strict'; var y; function f() { 'use strict'; var x; var y; f(); }", parserOptions: { ecmaVersion: 6, sourceType: "module" } },
 157         { code: "import * as foo from 'mod.js'; 'use strict'; var y; function f() { 'use strict'; var x; var y; f(); }", parserOptions: { ecmaVersion: 6, sourceType: "module" } },
 158         { code: "import { square, diag } from 'lib'; 'use strict'; var y; function f() { 'use strict'; var x; var y; f(); }", parserOptions: { ecmaVersion: 6, sourceType: "module" } },
 159         { code: "import { default as foo } from 'lib'; 'use strict'; var y; function f() { 'use strict'; var x; var y; f(); }", parserOptions: { ecmaVersion: 6, sourceType: "module" } },
 160         { code: "import 'src/mylib'; 'use strict'; var y; function f() { 'use strict'; var x; var y; f(); }", parserOptions: { ecmaVersion: 6, sourceType: "module" } },
 161         { code: "import theDefault, { named1, named2 } from 'src/mylib'; 'use strict'; var y; function f() { 'use strict'; var x; var y; f(); }", parserOptions: { ecmaVersion: 6, sourceType: "module" } },
 162         {
 163             code: [
 164                 "export var x;",
 165                 "var y;",
 166                 "var z;"
 167             ].join("\n"),
 168             parserOptions: {
 169                 ecmaVersion: 6,
 170                 sourceType: "module"
 171             }
 172         },
 173         {
 174             code: [
 175                 "var x;",
 176                 "export var y;",
 177                 "var z;"
 178             ].join("\n"),
 179             parserOptions: {
 180                 ecmaVersion: 6,
 181                 sourceType: "module"
 182             }
 183         },
 184         {
 185             code: [
 186                 "var x;",
 187                 "var y;",
 188                 "export var z;"
 189             ].join("\n"),
 190             parserOptions: {
 191                 ecmaVersion: 6,
 192                 sourceType: "module"
 193             }
 194         },
 195         {
 196             code: [
 197                 "class C {",
 198                 "    static {",
 199                 "        var x;",
 200                 "    }",
 201                 "}"
 202             ].join("\n"),
 203             parserOptions: {
 204                 ecmaVersion: 2022
 205             }
 206         },
 207         {
 208             code: [
 209                 "class C {",
 210                 "    static {",
 211                 "        var x;",
 212                 "        foo();",
 213                 "    }",
 214                 "}"
 215             ].join("\n"),
 216             parserOptions: {
 217                 ecmaVersion: 2022
 218             }
 219         },
 220         {
 221             code: [
 222                 "class C {",
 223                 "    static {",
 224                 "        var x;",
 225                 "        var y;",
 226                 "    }",
 227                 "}"
 228             ].join("\n"),
 229             parserOptions: {
 230                 ecmaVersion: 2022
 231             }
 232         },
 233         {
 234             code: [
 235                 "class C {",
 236                 "    static {",
 237                 "        var x;",
 238                 "        var y;",
 239                 "        foo();",
 240                 "    }",
 241                 "}"
 242             ].join("\n"),
 243             parserOptions: {
 244                 ecmaVersion: 2022
 245             }
 246         },
 247         {
 248             code: [
 249                 "class C {",
 250                 "    static {",
 251                 "        let x;",
 252                 "        var y;",
 253                 "    }",
 254                 "}"
 255             ].join("\n"),
 256             parserOptions: {
 257                 ecmaVersion: 2022
 258             }
 259         },
 260         {
 261             code: [
 262                 "class C {",
 263                 "    static {",
 264                 "        foo();",
 265                 "        let x;",
 266                 "    }",
 267                 "}"
 268             ].join("\n"),
 269             parserOptions: {
 270                 ecmaVersion: 2022
 271             }
 272         }
 273     ],
 274
 275     invalid: [
 276         {
 277             code: [
 278                 "var first = 0;",
 279                 "function foo() {",
 280                 "    first = 2;",
 281                 "    second = 2;",
 282                 "}",
 283                 "var second = 0;"
 284             ].join("\n"),
 285             errors: [error]
 286         },
 287         {
 288             code: [
 289                 "function foo() {",
 290                 "   var first;",
 291                 "   first = 1;",
 292                 "   first = 2;",
 293                 "   first = 3;",
 294                 "   first = 4;",
 295                 "   var second = 1;",
 296                 "   second = 2;",
 297                 "   first = second;",
 298                 "}"
 299             ].join("\n"),
 300             errors: [error]
 301         },
 302         {
 303             code: [
 304                 "function foo() {",
 305                 "   var first;",
 306                 "   if (true) {",
 307                 "       var second = true;",
 308                 "   }",
 309                 "   first = second;",
 310                 "}"
 311             ].join("\n"),
 312             errors: [error]
 313         },
 314         {
 315             code: [
 316                 "function foo() {",
 317                 "   for (var i = 0; i < 10; i++) {",
 318                 "       alert(i);",
 319                 "   }",
 320                 "}"
 321             ].join("\n"),
 322             errors: [error]
 323         },
 324         {
 325             code: [
 326                 "function foo() {",
 327                 "   var first = 10;",
 328                 "   var i;",
 329                 "   for (i = 0; i < first; i ++) {",
 330                 "       var second = i;",
 331                 "   }",
 332                 "}"
 333             ].join("\n"),
 334             errors: [error]
 335         },
 336         {
 337             code: [
 338                 "function foo() {",
 339                 "   var first = 10;",
 340                 "   var i;",
 341                 "   switch (first) {",
 342                 "       case 10:",
 343                 "           var hello = 1;",
 344                 "           break;",
 345                 "   }",
 346                 "}"
 347             ].join("\n"),
 348             errors: [error]
 349         },
 350         {
 351             code: [
 352                 "function foo() {",
 353                 "   var first = 10;",
 354                 "   var i;",
 355                 "   try {",
 356                 "       var hello = 1;",
 357                 "   } catch (e) {",
 358                 "       alert('error');",
 359                 "   }",
 360                 "}"
 361             ].join("\n"),
 362             errors: [error]
 363         },
 364         {
 365             code: [
 366                 "function foo() {",
 367                 "   var first = 10;",
 368                 "   var i;",
 369                 "   try {",
 370                 "       asdf;",
 371                 "   } catch (e) {",
 372                 "       var hello = 1;",
 373                 "   }",
 374                 "}"
 375             ].join("\n"),
 376             errors: [error]
 377         },
 378         {
 379             code: [
 380                 "function foo() {",
 381                 "   var first = 10;",
 382                 "   while (first) {",
 383                 "       var hello = 1;",
 384                 "   }",
 385                 "}"
 386             ].join("\n"),
 387             errors: [error]
 388         },
 389         {
 390             code: [
 391                 "function foo() {",
 392                 "   var first = 10;",
 393                 "   do {",
 394                 "       var hello = 1;",
 395                 "   } while (first == 10);",
 396                 "}"
 397             ].join("\n"),
 398             errors: [error]
 399         },
 400         {
 401             code: [
 402                 "function foo() {",
 403                 "   var first = [1,2,3];",
 404                 "   for (var item in first) {",
 405                 "       item++;",
 406                 "   }",
 407                 "}"
 408             ].join("\n"),
 409             errors: [error]
 410         },
 411         {
 412             code: [
 413                 "function foo() {",
 414                 "   var first = [1,2,3];",
 415                 "   var item;",
 416                 "   for (item in first) {",
 417                 "       var hello = item;",
 418                 "   }",
 419                 "}"
 420             ].join("\n"),
 421             errors: [error]
 422         },
 423         {
 424             code: [
 425                 "var foo = () => {",
 426                 "   var first = [1,2,3];",
 427                 "   var item;",
 428                 "   for (item in first) {",
 429                 "       var hello = item;",
 430                 "   }",
 431                 "}"
 432             ].join("\n"),
 433             parserOptions: { ecmaVersion: 6 },
 434             errors: [error]
 435         },
 436         {
 437             code: "'use strict'; 0; var x; f();",
 438             errors: [error]
 439         },
 440         {
 441             code: "'use strict'; var x; 'directive'; var y; f();",
 442             errors: [error]
 443         },
 444         {
 445             code: "function f() { 'use strict'; 0; var x; f(); }",
 446             errors: [error]
 447         },
 448         {
 449             code: "function f() { 'use strict'; var x; 'directive';  var y; f(); }",
 450             errors: [error]
 451         },
 452         {
 453             code: [
 454                 "export function f() {}",
 455                 "var x;"
 456             ].join("\n"),
 457             parserOptions: {
 458                 ecmaVersion: 6,
 459                 sourceType: "module"
 460             },
 461             errors: [error]
 462         },
 463         {
 464             code: [
 465                 "var x;",
 466                 "export function f() {}",
 467                 "var y;"
 468             ].join("\n"),
 469             parserOptions: {
 470                 ecmaVersion: 6,
 471                 sourceType: "module"
 472             },
 473             errors: [error]
 474         },
 475         {
 476             code: [
 477                 "import {foo} from 'foo';",
 478                 "export {foo};",
 479                 "var test = 1;"
 480             ].join("\n"),
 481             parserOptions: {
 482                 ecmaVersion: 6,
 483                 sourceType: "module"
 484             },
 485             errors: [error]
 486         },
 487         {
 488             code: [
 489                 "export {foo} from 'foo';",
 490                 "var test = 1;"
 491             ].join("\n"),
 492             parserOptions: {
 493                 ecmaVersion: 6,
 494                 sourceType: "module"
 495             },
 496             errors: [error]
 497         },
 498         {
 499             code: [
 500                 "export * from 'foo';",
 501                 "var test = 1;"
 502             ].join("\n"),
 503             parserOptions: {
 504                 ecmaVersion: 6,
 505                 sourceType: "module"
 506             },
 507             errors: [error]
 508         },
 509         {
 510             code: [
 511                 "class C {",
 512                 "    static {",
 513                 "        foo();",
 514                 "        var x;",
 515                 "    }",
 516                 "}"
 517             ].join("\n"),
 518             parserOptions: {
 519                 ecmaVersion: 2022
 520             },
 521             errors: [error]
 522         },
 523         {
 524             code: [
 525                 "class C {",
 526                 "    static {",
 527                 "        'use strict';", // static blocks do not have directives
 528                 "        var x;",
 529                 "    }",
 530                 "}"
 531             ].join("\n"),
 532             parserOptions: {
 533                 ecmaVersion: 2022
 534             },
 535             errors: [error]
 536         },
 537         {
 538             code: [
 539                 "class C {",
 540                 "    static {",
 541                 "        var x;",
 542                 "        foo();",
 543                 "        var y;",
 544                 "    }",
 545                 "}"
 546             ].join("\n"),
 547             parserOptions: {
 548                 ecmaVersion: 2022
 549             },
 550             errors: [{ ...error, line: 5 }]
 551         },
 552         {
 553             code: [
 554                 "class C {",
 555                 "    static {",
 556                 "        if (foo) {",
 557                 "            var x;",
 558                 "        }",
 559                 "    }",
 560                 "}"
 561             ].join("\n"),
 562             parserOptions: {
 563                 ecmaVersion: 2022
 564             },
 565             errors: [error]
 566         },
 567         {
 568             code: [
 569                 "class C {",
 570                 "    static {",
 571                 "        if (foo)",
 572                 "            var x;",
 573                 "    }",
 574                 "}"
 575             ].join("\n"),
 576             parserOptions: {
 577                 ecmaVersion: 2022
 578             },
 579             errors: [error]
 580         }
 581     ]
 582 });