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author | Michaël Zasso <targos@protonmail.com> | 2017-12-22 16:53:42 +0100 |
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committer | Michaël Zasso <targos@protonmail.com> | 2018-01-11 09:48:05 +0100 |
commit | 3dc30632755713179f345f4af024bd904c6162d0 (patch) | |
tree | f28c4f6dd6dfc5992edf301449d1a371d229755b /tools/node_modules/eslint/lib/rules/prefer-promise-reject-errors.js | |
parent | a2c7085dd4a8e60d1a47572aca8bb6fcb7a32f88 (diff) | |
download | android-node-v8-3dc30632755713179f345f4af024bd904c6162d0.tar.gz android-node-v8-3dc30632755713179f345f4af024bd904c6162d0.tar.bz2 android-node-v8-3dc30632755713179f345f4af024bd904c6162d0.zip |
tools: move eslint from tools to tools/node_modules
This is required because we need to add the babel-eslint dependency
and it has to be able to resolve "eslint".
babel-eslint is required to support future ES features such as async
iterators and import.meta.
Refs: https://github.com/nodejs/node/pull/17755
PR-URL: https://github.com/nodejs/node/pull/17820
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Diffstat (limited to 'tools/node_modules/eslint/lib/rules/prefer-promise-reject-errors.js')
-rw-r--r-- | tools/node_modules/eslint/lib/rules/prefer-promise-reject-errors.js | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/tools/node_modules/eslint/lib/rules/prefer-promise-reject-errors.js b/tools/node_modules/eslint/lib/rules/prefer-promise-reject-errors.js new file mode 100644 index 0000000000..d2a6b5df10 --- /dev/null +++ b/tools/node_modules/eslint/lib/rules/prefer-promise-reject-errors.js @@ -0,0 +1,124 @@ +/** + * @fileoverview restrict values that can be used as Promise rejection reasons + * @author Teddy Katz + */ +"use strict"; + +const astUtils = require("../ast-utils"); + +//------------------------------------------------------------------------------ +// Rule Definition +//------------------------------------------------------------------------------ + +module.exports = { + meta: { + docs: { + description: "require using Error objects as Promise rejection reasons", + category: "Best Practices", + recommended: false + }, + fixable: null, + schema: [ + { + type: "object", + properties: { + allowEmptyReject: { type: "boolean" } + }, + additionalProperties: false + } + ] + }, + + create(context) { + + const ALLOW_EMPTY_REJECT = context.options.length && context.options[0].allowEmptyReject; + + //---------------------------------------------------------------------- + // Helpers + //---------------------------------------------------------------------- + + /** + * Checks the argument of a reject() or Promise.reject() CallExpression, and reports it if it can't be an Error + * @param {ASTNode} callExpression A CallExpression node which is used to reject a Promise + * @returns {void} + */ + function checkRejectCall(callExpression) { + if (!callExpression.arguments.length && ALLOW_EMPTY_REJECT) { + return; + } + if ( + !callExpression.arguments.length || + !astUtils.couldBeError(callExpression.arguments[0]) || + callExpression.arguments[0].type === "Identifier" && callExpression.arguments[0].name === "undefined" + ) { + context.report({ + node: callExpression, + message: "Expected the Promise rejection reason to be an Error." + }); + } + } + + /** + * Determines whether a function call is a Promise.reject() call + * @param {ASTNode} node A CallExpression node + * @returns {boolean} `true` if the call is a Promise.reject() call + */ + function isPromiseRejectCall(node) { + return node.callee.type === "MemberExpression" && + node.callee.object.type === "Identifier" && node.callee.object.name === "Promise" && + node.callee.property.type === "Identifier" && node.callee.property.name === "reject"; + } + + //---------------------------------------------------------------------- + // Public + //---------------------------------------------------------------------- + + return { + + // Check `Promise.reject(value)` calls. + CallExpression(node) { + if (isPromiseRejectCall(node)) { + checkRejectCall(node); + } + }, + + /* + * Check for `new Promise((resolve, reject) => {})`, and check for reject() calls. + * This function is run on "NewExpression:exit" instead of "NewExpression" to ensure that + * the nodes in the expression already have the `parent` property. + */ + "NewExpression:exit"(node) { + if ( + node.callee.type === "Identifier" && node.callee.name === "Promise" && + node.arguments.length && astUtils.isFunction(node.arguments[0]) && + node.arguments[0].params.length > 1 && node.arguments[0].params[1].type === "Identifier" + ) { + context.getDeclaredVariables(node.arguments[0]) + + /* + * Find the first variable that matches the second parameter's name. + * If the first parameter has the same name as the second parameter, then the variable will actually + * be "declared" when the first parameter is evaluated, but then it will be immediately overwritten + * by the second parameter. It's not possible for an expression with the variable to be evaluated before + * the variable is overwritten, because functions with duplicate parameters cannot have destructuring or + * default assignments in their parameter lists. Therefore, it's not necessary to explicitly account for + * this case. + */ + .find(variable => variable.name === node.arguments[0].params[1].name) + + // Get the references to that variable. + .references + + // Only check the references that read the parameter's value. + .filter(ref => ref.isRead()) + + // Only check the references that are used as the callee in a function call, e.g. `reject(foo)`. + .filter(ref => ref.identifier.parent.type === "CallExpression" && ref.identifier === ref.identifier.parent.callee) + + // Check the argument of the function call to determine whether it's an Error. + .forEach(ref => checkRejectCall(ref.identifier.parent)); + } + } + }; + } +}; |