.config/coc/extensions/node_modules/coc-prettier/node_modules/eslint/lib/rules/padded-blocks.js

   1 /**
   2  * @fileoverview A rule to ensure blank lines within blocks.
   3  * @author Mathias Schreck <https://github.com/lo1tuma>
   4  */
   5
   6 "use strict";
   7
   8 //------------------------------------------------------------------------------
   9 // Requirements
  10 //------------------------------------------------------------------------------
  11
  12 const astUtils = require("./utils/ast-utils");
  13
  14 //------------------------------------------------------------------------------
  15 // Rule Definition
  16 //------------------------------------------------------------------------------
  17
  18 module.exports = {
  19     meta: {
  20         type: "layout",
  21
  22         docs: {
  23             description: "require or disallow padding within blocks",
  24             category: "Stylistic Issues",
  25             recommended: false,
  26             url: "https://eslint.org/docs/rules/padded-blocks"
  27         },
  28
  29         fixable: "whitespace",
  30
  31         schema: [
  32             {
  33                 oneOf: [
  34                     {
  35                         enum: ["always", "never"]
  36                     },
  37                     {
  38                         type: "object",
  39                         properties: {
  40                             blocks: {
  41                                 enum: ["always", "never"]
  42                             },
  43                             switches: {
  44                                 enum: ["always", "never"]
  45                             },
  46                             classes: {
  47                                 enum: ["always", "never"]
  48                             }
  49                         },
  50                         additionalProperties: false,
  51                         minProperties: 1
  52                     }
  53                 ]
  54             },
  55             {
  56                 type: "object",
  57                 properties: {
  58                     allowSingleLineBlocks: {
  59                         type: "boolean"
  60                     }
  61                 },
  62                 additionalProperties: false
  63             }
  64         ],
  65
  66         messages: {
  67             alwaysPadBlock: "Block must be padded by blank lines.",
  68             neverPadBlock: "Block must not be padded by blank lines."
  69         }
  70     },
  71
  72     create(context) {
  73         const options = {};
  74         const typeOptions = context.options[0] || "always";
  75         const exceptOptions = context.options[1] || {};
  76
  77         if (typeof typeOptions === "string") {
  78             const shouldHavePadding = typeOptions === "always";
  79
  80             options.blocks = shouldHavePadding;
  81             options.switches = shouldHavePadding;
  82             options.classes = shouldHavePadding;
  83         } else {
  84             if (Object.prototype.hasOwnProperty.call(typeOptions, "blocks")) {
  85                 options.blocks = typeOptions.blocks === "always";
  86             }
  87             if (Object.prototype.hasOwnProperty.call(typeOptions, "switches")) {
  88                 options.switches = typeOptions.switches === "always";
  89             }
  90             if (Object.prototype.hasOwnProperty.call(typeOptions, "classes")) {
  91                 options.classes = typeOptions.classes === "always";
  92             }
  93         }
  94
  95         if (Object.prototype.hasOwnProperty.call(exceptOptions, "allowSingleLineBlocks")) {
  96             options.allowSingleLineBlocks = exceptOptions.allowSingleLineBlocks === true;
  97         }
  98
  99         const sourceCode = context.getSourceCode();
 100
 101         /**
 102          * Gets the open brace token from a given node.
 103          * @param {ASTNode} node A BlockStatement or SwitchStatement node from which to get the open brace.
 104          * @returns {Token} The token of the open brace.
 105          */
 106         function getOpenBrace(node) {
 107             if (node.type === "SwitchStatement") {
 108                 return sourceCode.getTokenBefore(node.cases[0]);
 109             }
 110             return sourceCode.getFirstToken(node);
 111         }
 112
 113         /**
 114          * Checks if the given parameter is a comment node
 115          * @param {ASTNode|Token} node An AST node or token
 116          * @returns {boolean} True if node is a comment
 117          */
 118         function isComment(node) {
 119             return node.type === "Line" || node.type === "Block";
 120         }
 121
 122         /**
 123          * Checks if there is padding between two tokens
 124          * @param {Token} first The first token
 125          * @param {Token} second The second token
 126          * @returns {boolean} True if there is at least a line between the tokens
 127          */
 128         function isPaddingBetweenTokens(first, second) {
 129             return second.loc.start.line - first.loc.end.line >= 2;
 130         }
 131
 132
 133         /**
 134          * Checks if the given token has a blank line after it.
 135          * @param {Token} token The token to check.
 136          * @returns {boolean} Whether or not the token is followed by a blank line.
 137          */
 138         function getFirstBlockToken(token) {
 139             let prev,
 140                 first = token;
 141
 142             do {
 143                 prev = first;
 144                 first = sourceCode.getTokenAfter(first, { includeComments: true });
 145             } while (isComment(first) && first.loc.start.line === prev.loc.end.line);
 146
 147             return first;
 148         }
 149
 150         /**
 151          * Checks if the given token is preceded by a blank line.
 152          * @param {Token} token The token to check
 153          * @returns {boolean} Whether or not the token is preceded by a blank line
 154          */
 155         function getLastBlockToken(token) {
 156             let last = token,
 157                 next;
 158
 159             do {
 160                 next = last;
 161                 last = sourceCode.getTokenBefore(last, { includeComments: true });
 162             } while (isComment(last) && last.loc.end.line === next.loc.start.line);
 163
 164             return last;
 165         }
 166
 167         /**
 168          * Checks if a node should be padded, according to the rule config.
 169          * @param {ASTNode} node The AST node to check.
 170          * @returns {boolean} True if the node should be padded, false otherwise.
 171          */
 172         function requirePaddingFor(node) {
 173             switch (node.type) {
 174                 case "BlockStatement":
 175                     return options.blocks;
 176                 case "SwitchStatement":
 177                     return options.switches;
 178                 case "ClassBody":
 179                     return options.classes;
 180
 181                 /* istanbul ignore next */
 182                 default:
 183                     throw new Error("unreachable");
 184             }
 185         }
 186
 187         /**
 188          * Checks the given BlockStatement node to be padded if the block is not empty.
 189          * @param {ASTNode} node The AST node of a BlockStatement.
 190          * @returns {void} undefined.
 191          */
 192         function checkPadding(node) {
 193             const openBrace = getOpenBrace(node),
 194                 firstBlockToken = getFirstBlockToken(openBrace),
 195                 tokenBeforeFirst = sourceCode.getTokenBefore(firstBlockToken, { includeComments: true }),
 196                 closeBrace = sourceCode.getLastToken(node),
 197                 lastBlockToken = getLastBlockToken(closeBrace),
 198                 tokenAfterLast = sourceCode.getTokenAfter(lastBlockToken, { includeComments: true }),
 199                 blockHasTopPadding = isPaddingBetweenTokens(tokenBeforeFirst, firstBlockToken),
 200                 blockHasBottomPadding = isPaddingBetweenTokens(lastBlockToken, tokenAfterLast);
 201
 202             if (options.allowSingleLineBlocks && astUtils.isTokenOnSameLine(tokenBeforeFirst, tokenAfterLast)) {
 203                 return;
 204             }
 205
 206             if (requirePaddingFor(node)) {
 207
 208                 if (!blockHasTopPadding) {
 209                     context.report({
 210                         node,
 211                         loc: {
 212                             start: tokenBeforeFirst.loc.start,
 213                             end: firstBlockToken.loc.start
 214                         },
 215                         fix(fixer) {
 216                             return fixer.insertTextAfter(tokenBeforeFirst, "\n");
 217                         },
 218                         messageId: "alwaysPadBlock"
 219                     });
 220                 }
 221                 if (!blockHasBottomPadding) {
 222                     context.report({
 223                         node,
 224                         loc: {
 225                             end: tokenAfterLast.loc.start,
 226                             start: lastBlockToken.loc.end
 227                         },
 228                         fix(fixer) {
 229                             return fixer.insertTextBefore(tokenAfterLast, "\n");
 230                         },
 231                         messageId: "alwaysPadBlock"
 232                     });
 233                 }
 234             } else {
 235                 if (blockHasTopPadding) {
 236
 237                     context.report({
 238                         node,
 239                         loc: {
 240                             start: tokenBeforeFirst.loc.start,
 241                             end: firstBlockToken.loc.start
 242                         },
 243                         fix(fixer) {
 244                             return fixer.replaceTextRange([tokenBeforeFirst.range[1], firstBlockToken.range[0] - firstBlockToken.loc.start.column], "\n");
 245                         },
 246                         messageId: "neverPadBlock"
 247                     });
 248                 }
 249
 250                 if (blockHasBottomPadding) {
 251
 252                     context.report({
 253                         node,
 254                         loc: {
 255                             end: tokenAfterLast.loc.start,
 256                             start: lastBlockToken.loc.end
 257                         },
 258                         messageId: "neverPadBlock",
 259                         fix(fixer) {
 260                             return fixer.replaceTextRange([lastBlockToken.range[1], tokenAfterLast.range[0] - tokenAfterLast.loc.start.column], "\n");
 261                         }
 262                     });
 263                 }
 264             }
 265         }
 266
 267         const rule = {};
 268
 269         if (Object.prototype.hasOwnProperty.call(options, "switches")) {
 270             rule.SwitchStatement = function(node) {
 271                 if (node.cases.length === 0) {
 272                     return;
 273                 }
 274                 checkPadding(node);
 275             };
 276         }
 277
 278         if (Object.prototype.hasOwnProperty.call(options, "blocks")) {
 279             rule.BlockStatement = function(node) {
 280                 if (node.body.length === 0) {
 281                     return;
 282                 }
 283                 checkPadding(node);
 284             };
 285         }
 286
 287         if (Object.prototype.hasOwnProperty.call(options, "classes")) {
 288             rule.ClassBody = function(node) {
 289                 if (node.body.length === 0) {
 290                     return;
 291                 }
 292                 checkPadding(node);
 293             };
 294         }
 295
 296         return rule;
 297     }
 298 };