eslint/tests/lib/rules/no-multiple-empty-lines.js

   1 /**
   2  * @fileoverview Disallows multiple blank lines.
   3  * @author Greg Cochard
   4  */
   5 "use strict";
   6
   7 //------------------------------------------------------------------------------
   8 // Requirements
   9 //------------------------------------------------------------------------------
  10
  11 const rule = require("../../../lib/rules/no-multiple-empty-lines"),
  12     { RuleTester } = require("../../../lib/rule-tester");
  13
  14 //------------------------------------------------------------------------------
  15 // Tests
  16 //------------------------------------------------------------------------------
  17
  18 const ruleTester = new RuleTester();
  19
  20 /**
  21  * Creates the expected error message object for the specified number of lines
  22  * @param {lines} lines The number of lines expected.
  23  * @returns {Object} the expected error message object
  24  * @private
  25  */
  26 function getExpectedError(lines) {
  27     return {
  28         messageId: "consecutiveBlank",
  29         data: {
  30             max: lines,
  31             pluralizedLines: lines === 1 ? "line" : "lines"
  32         },
  33         type: "Program",
  34         column: 1
  35     };
  36 }
  37
  38 /**
  39  * Creates the expected error message object for the specified number of lines
  40  * @param {lines} lines The number of lines expected.
  41  * @returns {Object} the expected error message object
  42  * @private
  43  */
  44 function getExpectedErrorEOF(lines) {
  45     return {
  46         messageId: "blankEndOfFile",
  47         data: {
  48             max: lines
  49         },
  50         type: "Program",
  51         column: 1
  52     };
  53 }
  54
  55 /**
  56  * Creates the expected error message object for the specified number of lines
  57  * @param {lines} lines The number of lines expected.
  58  * @returns {Object} the expected error message object
  59  * @private
  60  */
  61 function getExpectedErrorBOF(lines) {
  62     return {
  63         messageId: "blankBeginningOfFile",
  64         data: {
  65             max: lines
  66         },
  67         type: "Program",
  68         column: 1
  69     };
  70 }
  71
  72
  73 ruleTester.run("no-multiple-empty-lines", rule, {
  74
  75     valid: [
  76         {
  77             code: "// valid 1\nvar a = 5;\nvar b = 3;\n\n",
  78             options: [{ max: 1 }]
  79         },
  80         {
  81             code: "// valid 2\n\nvar a = 5;\n\nvar b = 3;",
  82             options: [{ max: 1 }]
  83         },
  84         {
  85             code: "// valid 3\nvar a = 5;\n\nvar b = 3;\n\n\n",
  86             options: [{ max: 2 }]
  87         },
  88         {
  89             code: "// valid 4\nvar a = 5,\n    b = 3;",
  90             options: [{ max: 2 }]
  91         },
  92         {
  93             code: "// valid 5\nvar a = 5;\n\n\n\n\nvar b = 3;\n\n\n\n\n",
  94             options: [{ max: 4 }]
  95         },
  96         {
  97             code: "// valid 6\nvar a = 5;\n/* comment */\nvar b = 5;",
  98             options: [{ max: 0 }]
  99         },
 100         {
 101             code: "// valid 7\nvar a = 5;\n",
 102             options: [{ max: 0 }]
 103         },
 104         {
 105             code: "// valid 8\nvar a = 5;\n",
 106             options: [{ max: 0, maxEOF: 0 }]
 107         },
 108         {
 109             code: "// valid 9\nvar a = 1;\n\n",
 110             options: [{ max: 2, maxEOF: 1 }]
 111         },
 112         {
 113             code: "// valid 10\nvar a = 5;\n",
 114             options: [{ max: 0, maxBOF: 0 }]
 115         },
 116         {
 117             code: "\n// valid 11\nvar a = 1;\n",
 118             options: [{ max: 2, maxBOF: 1 }]
 119         },
 120         {
 121             code: "// valid 12\r\n// windows line endings\r\nvar a = 5;\r\nvar b = 3;\r\n\r\n",
 122             options: [{ max: 1 }]
 123         },
 124
 125         // template strings
 126         {
 127             code: "// valid 12\nx = `\n\n\n\nhi\n\n\n\n`",
 128             options: [{ max: 2 }],
 129             parserOptions: { ecmaVersion: 6 }
 130         },
 131         {
 132             code: "// valid 13\n`\n\n`",
 133             options: [{ max: 0 }],
 134             parserOptions: { ecmaVersion: 6 }
 135         },
 136         {
 137             code: "// valid 14\nvar a = 5;`\n\n\n\n\n`",
 138             options: [{ max: 0, maxEOF: 0 }],
 139             parserOptions: { ecmaVersion: 6 }
 140         },
 141         {
 142             code: "`\n\n\n\n\n`\n// valid 15\nvar a = 5;",
 143             options: [{ max: 0, maxBOF: 0 }],
 144             parserOptions: { ecmaVersion: 6 }
 145         },
 146         {
 147             code: "\n\n\n\n// valid 16\nvar a = 5;\n",
 148             options: [{ max: 0, maxBOF: 4 }]
 149         },
 150         {
 151             code: "// valid 17\nvar a = 5;\n\n",
 152             options: [{ max: 0, maxEOF: 1 }]
 153         },
 154         {
 155             code: "var a = 5;",
 156             options: [{ max: 1 }]
 157         }
 158     ],
 159
 160     invalid: [
 161         {
 162             code: "// invalid 1\nvar a = 5;\n\n\nvar b = 3;",
 163             output: "// invalid 1\nvar a = 5;\n\nvar b = 3;",
 164             options: [{ max: 1 }],
 165             errors: [getExpectedError(1)]
 166         },
 167         {
 168             code: "// invalid 2\n\n\n\n\nvar a = 5;",
 169             output: "// invalid 2\n\n\nvar a = 5;",
 170             options: [{ max: 2 }],
 171             errors: [getExpectedError(2)]
 172         },
 173         {
 174             code: "// invalid 3\nvar a = 5;\n\n\n\n",
 175             output: "// invalid 3\nvar a = 5;\n\n\n",
 176             options: [{ max: 2 }],
 177             errors: [getExpectedErrorEOF(2)]
 178         },
 179         {
 180             code: "// invalid 4\nvar a = 5;\n \n \n \n",
 181             output: "// invalid 4\nvar a = 5;\n \n \n",
 182             options: [{ max: 2 }],
 183             errors: [getExpectedErrorEOF(2)]
 184         },
 185         {
 186             code: "// invalid 5\nvar a=5;\n\n\n\nvar b = 3;",
 187             output: "// invalid 5\nvar a=5;\n\n\nvar b = 3;",
 188             options: [{ max: 2 }],
 189             errors: [getExpectedError(2)]
 190         },
 191         {
 192             code: "// invalid 6\nvar a=5;\n\n\n\nvar b = 3;\n",
 193             output: "// invalid 6\nvar a=5;\n\n\nvar b = 3;\n",
 194             options: [{ max: 2 }],
 195             errors: [getExpectedError(2)]
 196         },
 197         {
 198             code: "// invalid 7\nvar a = 5;\n\n\n\nb = 3;\nvar c = 5;\n\n\n\nvar d = 3;",
 199             output: "// invalid 7\nvar a = 5;\n\n\nb = 3;\nvar c = 5;\n\n\nvar d = 3;",
 200             options: [{ max: 2 }],
 201             errors: 2
 202         },
 203         {
 204             code: "// invalid 8\nvar a = 5;\n\n\n\n\n\n\n\n\n\n\n\n\n\nb = 3;",
 205             output: "// invalid 8\nvar a = 5;\n\n\nb = 3;",
 206             options: [{ max: 2 }],
 207             errors: [getExpectedError(2)]
 208         },
 209         {
 210             code: "// invalid 9\nvar a=5;\n\n\n\n\n",
 211             output: "// invalid 9\nvar a=5;\n\n\n",
 212             options: [{ max: 2 }],
 213             errors: [getExpectedErrorEOF(2)]
 214         },
 215         {
 216             code: "// invalid 10\nvar a = 5;\n\nvar b = 3;",
 217             output: "// invalid 10\nvar a = 5;\nvar b = 3;",
 218             options: [{ max: 0 }],
 219             errors: [getExpectedError(0)]
 220         },
 221         {
 222             code: "// invalid 11\nvar a = 5;\n\n\n",
 223             output: "// invalid 11\nvar a = 5;\n\n",
 224             options: [{ max: 5, maxEOF: 1 }],
 225             errors: [getExpectedErrorEOF(1)]
 226         },
 227         {
 228             code: "// invalid 12\nvar a = 5;\n\n\n\n\n\n",
 229             output: "// invalid 12\nvar a = 5;\n\n\n\n\n",
 230             options: [{ max: 0, maxEOF: 4 }],
 231             errors: [getExpectedErrorEOF(4)]
 232         },
 233         {
 234             code: "// invalid 13\n\n\n\n\n\n\n\n\nvar a = 5;\n\n\n",
 235             output: "// invalid 13\n\n\n\n\n\n\n\n\nvar a = 5;\n\n",
 236             options: [{ max: 10, maxEOF: 1 }],
 237             errors: [getExpectedErrorEOF(1)]
 238         },
 239         {
 240             code: "// invalid 14\nvar a = 5;\n\n",
 241             output: "// invalid 14\nvar a = 5;\n",
 242             options: [{ max: 2, maxEOF: 0 }],
 243             errors: [getExpectedErrorEOF(0)]
 244         },
 245         {
 246             code: "\n\n// invalid 15\nvar a = 5;\n",
 247             output: "\n// invalid 15\nvar a = 5;\n",
 248             options: [{ max: 5, maxBOF: 1 }],
 249             errors: [getExpectedErrorBOF(1)]
 250         },
 251         {
 252             code: "\n\n\n\n\n// invalid 16\nvar a = 5;\n",
 253             output: "\n\n\n\n// invalid 16\nvar a = 5;\n",
 254             options: [{ max: 0, maxBOF: 4 }],
 255             errors: [getExpectedErrorBOF(4)]
 256         },
 257         {
 258             code: "\n\n// invalid 17\n\n\n\n\n\n\n\n\nvar a = 5;\n",
 259             output: "\n// invalid 17\n\n\n\n\n\n\n\n\nvar a = 5;\n",
 260             options: [{ max: 10, maxBOF: 1 }],
 261             errors: [getExpectedErrorBOF(1)]
 262         },
 263         {
 264             code: "\n// invalid 18\nvar a = 5;\n",
 265             output: "// invalid 18\nvar a = 5;\n",
 266             options: [{ max: 2, maxBOF: 0 }],
 267             errors: [getExpectedErrorBOF(0)]
 268         },
 269         {
 270             code: "\n\n\n// invalid 19\nvar a = 5;\n\n",
 271             output: "// invalid 19\nvar a = 5;\n",
 272             options: [{ max: 2, maxBOF: 0, maxEOF: 0 }],
 273             errors: [getExpectedErrorBOF(0),
 274                 getExpectedErrorEOF(0)]
 275         },
 276         {
 277             code: "// invalid 20\r\n// windows line endings\r\nvar a = 5;\r\nvar b = 3;\r\n\r\n\r\n",
 278             output: "// invalid 20\r\n// windows line endings\r\nvar a = 5;\r\nvar b = 3;\r\n\r\n",
 279             options: [{ max: 1 }],
 280             errors: [getExpectedErrorEOF(1)]
 281         },
 282         {
 283             code: "// invalid 21\n// unix line endings\nvar a = 5;\nvar b = 3;\n\n\n",
 284             output: "// invalid 21\n// unix line endings\nvar a = 5;\nvar b = 3;\n\n",
 285             options: [{ max: 1 }],
 286             errors: [getExpectedErrorEOF(1)]
 287         },
 288         {
 289             code:
 290             "'foo';\n" +
 291             "\n" +
 292             "\n" +
 293             "`bar`;\n" +
 294             "`baz`;",
 295             output:
 296             "'foo';\n" +
 297             "\n" +
 298             "`bar`;\n" +
 299             "`baz`;",
 300             options: [{ max: 1 }],
 301             parserOptions: { ecmaVersion: 6 },
 302             errors: [getExpectedError(1)]
 303         },
 304         {
 305             code: "`template ${foo\n\n\n} literal`;",
 306             output: "`template ${foo\n\n} literal`;",
 307             options: [{ max: 1 }],
 308             parserOptions: { ecmaVersion: 6 },
 309             errors: [getExpectedError(1)]
 310         },
 311         {
 312
 313             // https://github.com/eslint/eslint/issues/7893
 314             code: `a\n\n\n\n${"a".repeat(1e5)}`,
 315             output: `a\n\n\n${"a".repeat(1e5)}`,
 316             errors: [getExpectedError(2)]
 317         },
 318         {
 319
 320             // https://github.com/eslint/eslint/issues/8401
 321             code: "foo\n ",
 322             output: "foo\n",
 323             options: [{ max: 1, maxEOF: 0 }],
 324             errors: [getExpectedErrorEOF(0)]
 325         },
 326         {
 327
 328             // https://github.com/eslint/eslint/pull/12594
 329             code: "var a;\n\n\n\n\nvar b;",
 330             output: "var a;\n\nvar b;",
 331             options: [{ max: 1 }],
 332             errors: [{
 333                 messageId: "consecutiveBlank",
 334                 data: {
 335                     max: 1,
 336                     pluralizedLines: "line"
 337                 },
 338                 type: "Program",
 339                 line: 3,
 340                 column: 1
 341             }]
 342         },
 343         {
 344
 345             // https://github.com/eslint/eslint/pull/12594
 346             code: "var a;\n\n\n\n\nvar b;",
 347             output: "var a;\n\n\nvar b;",
 348             options: [{ max: 2 }],
 349             errors: [{
 350                 messageId: "consecutiveBlank",
 351                 data: {
 352                     max: 2,
 353                     pluralizedLines: "lines"
 354                 },
 355                 type: "Program",
 356                 line: 4,
 357                 column: 1
 358             }]
 359         }
 360     ]
 361 });