.gitignore added
[dotfiles/.git] / .config / coc / extensions / node_modules / coc-prettier / node_modules / eslint / lib / rules / brace-style.js
1 /**
2  * @fileoverview Rule to flag block statements that do not use the one true brace style
3  * @author Ian Christian Myers
4  */
5
6 "use strict";
7
8 const astUtils = require("./utils/ast-utils");
9
10 //------------------------------------------------------------------------------
11 // Rule Definition
12 //------------------------------------------------------------------------------
13
14 module.exports = {
15     meta: {
16         type: "layout",
17
18         docs: {
19             description: "enforce consistent brace style for blocks",
20             category: "Stylistic Issues",
21             recommended: false,
22             url: "https://eslint.org/docs/rules/brace-style"
23         },
24
25         schema: [
26             {
27                 enum: ["1tbs", "stroustrup", "allman"]
28             },
29             {
30                 type: "object",
31                 properties: {
32                     allowSingleLine: {
33                         type: "boolean",
34                         default: false
35                     }
36                 },
37                 additionalProperties: false
38             }
39         ],
40
41         fixable: "whitespace",
42
43         messages: {
44             nextLineOpen: "Opening curly brace does not appear on the same line as controlling statement.",
45             sameLineOpen: "Opening curly brace appears on the same line as controlling statement.",
46             blockSameLine: "Statement inside of curly braces should be on next line.",
47             nextLineClose: "Closing curly brace does not appear on the same line as the subsequent block.",
48             singleLineClose: "Closing curly brace should be on the same line as opening curly brace or on the line after the previous block.",
49             sameLineClose: "Closing curly brace appears on the same line as the subsequent block."
50         }
51     },
52
53     create(context) {
54         const style = context.options[0] || "1tbs",
55             params = context.options[1] || {},
56             sourceCode = context.getSourceCode();
57
58         //--------------------------------------------------------------------------
59         // Helpers
60         //--------------------------------------------------------------------------
61
62         /**
63          * Fixes a place where a newline unexpectedly appears
64          * @param {Token} firstToken The token before the unexpected newline
65          * @param {Token} secondToken The token after the unexpected newline
66          * @returns {Function} A fixer function to remove the newlines between the tokens
67          */
68         function removeNewlineBetween(firstToken, secondToken) {
69             const textRange = [firstToken.range[1], secondToken.range[0]];
70             const textBetween = sourceCode.text.slice(textRange[0], textRange[1]);
71
72             // Don't do a fix if there is a comment between the tokens
73             if (textBetween.trim()) {
74                 return null;
75             }
76             return fixer => fixer.replaceTextRange(textRange, " ");
77         }
78
79         /**
80          * Validates a pair of curly brackets based on the user's config
81          * @param {Token} openingCurly The opening curly bracket
82          * @param {Token} closingCurly The closing curly bracket
83          * @returns {void}
84          */
85         function validateCurlyPair(openingCurly, closingCurly) {
86             const tokenBeforeOpeningCurly = sourceCode.getTokenBefore(openingCurly);
87             const tokenAfterOpeningCurly = sourceCode.getTokenAfter(openingCurly);
88             const tokenBeforeClosingCurly = sourceCode.getTokenBefore(closingCurly);
89             const singleLineException = params.allowSingleLine && astUtils.isTokenOnSameLine(openingCurly, closingCurly);
90
91             if (style !== "allman" && !astUtils.isTokenOnSameLine(tokenBeforeOpeningCurly, openingCurly)) {
92                 context.report({
93                     node: openingCurly,
94                     messageId: "nextLineOpen",
95                     fix: removeNewlineBetween(tokenBeforeOpeningCurly, openingCurly)
96                 });
97             }
98
99             if (style === "allman" && astUtils.isTokenOnSameLine(tokenBeforeOpeningCurly, openingCurly) && !singleLineException) {
100                 context.report({
101                     node: openingCurly,
102                     messageId: "sameLineOpen",
103                     fix: fixer => fixer.insertTextBefore(openingCurly, "\n")
104                 });
105             }
106
107             if (astUtils.isTokenOnSameLine(openingCurly, tokenAfterOpeningCurly) && tokenAfterOpeningCurly !== closingCurly && !singleLineException) {
108                 context.report({
109                     node: openingCurly,
110                     messageId: "blockSameLine",
111                     fix: fixer => fixer.insertTextAfter(openingCurly, "\n")
112                 });
113             }
114
115             if (tokenBeforeClosingCurly !== openingCurly && !singleLineException && astUtils.isTokenOnSameLine(tokenBeforeClosingCurly, closingCurly)) {
116                 context.report({
117                     node: closingCurly,
118                     messageId: "singleLineClose",
119                     fix: fixer => fixer.insertTextBefore(closingCurly, "\n")
120                 });
121             }
122         }
123
124         /**
125          * Validates the location of a token that appears before a keyword (e.g. a newline before `else`)
126          * @param {Token} curlyToken The closing curly token. This is assumed to precede a keyword token (such as `else` or `finally`).
127          * @returns {void}
128          */
129         function validateCurlyBeforeKeyword(curlyToken) {
130             const keywordToken = sourceCode.getTokenAfter(curlyToken);
131
132             if (style === "1tbs" && !astUtils.isTokenOnSameLine(curlyToken, keywordToken)) {
133                 context.report({
134                     node: curlyToken,
135                     messageId: "nextLineClose",
136                     fix: removeNewlineBetween(curlyToken, keywordToken)
137                 });
138             }
139
140             if (style !== "1tbs" && astUtils.isTokenOnSameLine(curlyToken, keywordToken)) {
141                 context.report({
142                     node: curlyToken,
143                     messageId: "sameLineClose",
144                     fix: fixer => fixer.insertTextAfter(curlyToken, "\n")
145                 });
146             }
147         }
148
149         //--------------------------------------------------------------------------
150         // Public API
151         //--------------------------------------------------------------------------
152
153         return {
154             BlockStatement(node) {
155                 if (!astUtils.STATEMENT_LIST_PARENTS.has(node.parent.type)) {
156                     validateCurlyPair(sourceCode.getFirstToken(node), sourceCode.getLastToken(node));
157                 }
158             },
159             ClassBody(node) {
160                 validateCurlyPair(sourceCode.getFirstToken(node), sourceCode.getLastToken(node));
161             },
162             SwitchStatement(node) {
163                 const closingCurly = sourceCode.getLastToken(node);
164                 const openingCurly = sourceCode.getTokenBefore(node.cases.length ? node.cases[0] : closingCurly);
165
166                 validateCurlyPair(openingCurly, closingCurly);
167             },
168             IfStatement(node) {
169                 if (node.consequent.type === "BlockStatement" && node.alternate) {
170
171                     // Handle the keyword after the `if` block (before `else`)
172                     validateCurlyBeforeKeyword(sourceCode.getLastToken(node.consequent));
173                 }
174             },
175             TryStatement(node) {
176
177                 // Handle the keyword after the `try` block (before `catch` or `finally`)
178                 validateCurlyBeforeKeyword(sourceCode.getLastToken(node.block));
179
180                 if (node.handler && node.finalizer) {
181
182                     // Handle the keyword after the `catch` block (before `finally`)
183                     validateCurlyBeforeKeyword(sourceCode.getLastToken(node.handler.body));
184                 }
185             }
186         };
187     }
188 };