odin-javascript-exercises/node_modules/eslint/lib/rules/switch-colon-spacing.js
2017-12-15 12:56:14 -06:00

133 lines
4.9 KiB
JavaScript

/**
* @fileoverview Rule to enforce spacing around colons of switch statements.
* @author Toru Nagashima
*/
"use strict";
//------------------------------------------------------------------------------
// Requirements
//------------------------------------------------------------------------------
const astUtils = require("../ast-utils");
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------
module.exports = {
meta: {
docs: {
description: "enforce spacing around colons of switch statements",
category: "Stylistic Issues",
recommended: false
},
schema: [
{
type: "object",
properties: {
before: { type: "boolean" },
after: { type: "boolean" }
},
additionalProperties: false
}
],
fixable: "whitespace"
},
create(context) {
const sourceCode = context.getSourceCode();
const options = context.options[0] || {};
const beforeSpacing = options.before === true; // false by default
const afterSpacing = options.after !== false; // true by default
/**
* Get the colon token of the given SwitchCase node.
* @param {ASTNode} node The SwitchCase node to get.
* @returns {Token} The colon token of the node.
*/
function getColonToken(node) {
if (node.test) {
return sourceCode.getTokenAfter(node.test, astUtils.isColonToken);
}
return sourceCode.getFirstToken(node, 1);
}
/**
* Check whether the spacing between the given 2 tokens is valid or not.
* @param {Token} left The left token to check.
* @param {Token} right The right token to check.
* @param {boolean} expected The expected spacing to check. `true` if there should be a space.
* @returns {boolean} `true` if the spacing between the tokens is valid.
*/
function isValidSpacing(left, right, expected) {
return (
astUtils.isClosingBraceToken(right) ||
!astUtils.isTokenOnSameLine(left, right) ||
sourceCode.isSpaceBetweenTokens(left, right) === expected
);
}
/**
* Check whether comments exist between the given 2 tokens.
* @param {Token} left The left token to check.
* @param {Token} right The right token to check.
* @returns {boolean} `true` if comments exist between the given 2 tokens.
*/
function commentsExistBetween(left, right) {
return sourceCode.getFirstTokenBetween(
left,
right,
{
includeComments: true,
filter: astUtils.isCommentToken
}
) !== null;
}
/**
* Fix the spacing between the given 2 tokens.
* @param {RuleFixer} fixer The fixer to fix.
* @param {Token} left The left token of fix range.
* @param {Token} right The right token of fix range.
* @param {boolean} spacing The spacing style. `true` if there should be a space.
* @returns {Fix|null} The fix object.
*/
function fix(fixer, left, right, spacing) {
if (commentsExistBetween(left, right)) {
return null;
}
if (spacing) {
return fixer.insertTextAfter(left, " ");
}
return fixer.removeRange([left.range[1], right.range[0]]);
}
return {
SwitchCase(node) {
const colonToken = getColonToken(node);
const beforeToken = sourceCode.getTokenBefore(colonToken);
const afterToken = sourceCode.getTokenAfter(colonToken);
if (!isValidSpacing(beforeToken, colonToken, beforeSpacing)) {
context.report({
node,
loc: colonToken.loc,
message: "{{verb}} space(s) before this colon.",
data: { verb: beforeSpacing ? "Expected" : "Unexpected" },
fix: fixer => fix(fixer, beforeToken, colonToken, beforeSpacing)
});
}
if (!isValidSpacing(colonToken, afterToken, afterSpacing)) {
context.report({
node,
loc: colonToken.loc,
message: "{{verb}} space(s) after this colon.",
data: { verb: afterSpacing ? "Expected" : "Unexpected" },
fix: fixer => fix(fixer, colonToken, afterToken, afterSpacing)
});
}
}
};
}
};