github-pages-deploy-action/node_modules/tslint/lib/rules/unnecessaryBindRule.js
2019-11-19 07:48:29 -05:00

129 lines
5.4 KiB
JavaScript

"use strict";
/**
* @license
* Copyright 2017 Palantir Technologies, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
Object.defineProperty(exports, "__esModule", { value: true });
var tslib_1 = require("tslib");
var tsutils = require("tsutils");
var ts = require("typescript");
var Lint = require("../index");
var Rule = /** @class */ (function (_super) {
tslib_1.__extends(Rule, _super);
function Rule() {
return _super !== null && _super.apply(this, arguments) || this;
}
Rule.prototype.apply = function (sourceFile) {
return this.applyWithFunction(sourceFile, walk);
};
Rule.prototype.applyWithProgram = function (sourceFile, program) {
return this.applyWithFunction(sourceFile, walk, undefined, program.getTypeChecker());
};
Rule.metadata = {
description: "Prevents unnecessary and/or misleading scope bindings on functions.",
optionExamples: [true],
options: null,
optionsDescription: "Not configurable.",
rationale: Lint.Utils.dedent(templateObject_1 || (templateObject_1 = tslib_1.__makeTemplateObject(["\n `function` expressions that are immediately bound to `this` are equivalent to `() =>` arrow lambdas.\n Additionally, there's no use in binding a scope to an arrow lambda, as it already has one.\n "], ["\n \\`function\\` expressions that are immediately bound to \\`this\\` are equivalent to \\`() =>\\` arrow lambdas.\n Additionally, there's no use in binding a scope to an arrow lambda, as it already has one.\n "]))),
requiresTypeInfo: true,
ruleName: "unnecessary-bind",
type: "style",
typescriptOnly: false,
};
Rule.FAILURE_STRING_FUNCTION = "Don't bind `this` without arguments as a scope to a function. Use an arrow lambda instead.";
Rule.FAILURE_STRING_ARROW = "Don't bind scopes to arrow lambdas, as they already have a bound scope.";
return Rule;
}(Lint.Rules.OptionallyTypedRule));
exports.Rule = Rule;
function walk(context, typeChecker) {
var variableUsage = tsutils.collectVariableUsage(context.sourceFile);
function checkArrowFunction(node) {
if (node.arguments.length !== 1) {
return;
}
context.addFailureAtNode(node, Rule.FAILURE_STRING_ARROW);
}
function canFunctionExpressionBeFixed(callExpression, valueDeclaration) {
if (callExpression.arguments.length !== 1 ||
callExpression.arguments[0].kind !== ts.SyntaxKind.ThisKeyword ||
valueDeclaration.asteriskToken !== undefined ||
valueDeclaration.decorators !== undefined) {
return false;
}
var name = valueDeclaration.name;
if (name === undefined) {
return true;
}
var nameInfo = variableUsage.get(name);
return nameInfo === undefined || nameInfo.uses.length === 0;
}
function checkFunctionExpression(callExpression, valueDeclaration) {
if (!canFunctionExpressionBeFixed(callExpression, valueDeclaration)) {
return;
}
context.addFailureAtNode(callExpression, Rule.FAILURE_STRING_FUNCTION);
}
function getArrowFunctionDeclaration(node) {
if (typeChecker === undefined) {
return undefined;
}
var symbol = typeChecker.getTypeAtLocation(node).symbol;
if (symbol === undefined) {
return undefined;
}
var valueDeclaration = symbol.valueDeclaration;
if (valueDeclaration === undefined) {
return undefined;
}
if (!tsutils.isArrowFunction(valueDeclaration)) {
return undefined;
}
return valueDeclaration;
}
function isDecoratedPropertyMember(node) {
return (node.parent !== undefined &&
tsutils.isPropertyDeclaration(node.parent) &&
node.parent.decorators !== undefined);
}
function checkCallExpression(node) {
if (isDecoratedPropertyMember(node)) {
return;
}
var bindExpression = node.expression;
if (!isBindPropertyAccess(bindExpression)) {
return;
}
var boundExpression = Lint.unwrapParentheses(bindExpression.expression);
if (tsutils.isFunctionExpression(boundExpression)) {
checkFunctionExpression(node, boundExpression);
return;
}
var valueDeclaration = getArrowFunctionDeclaration(boundExpression);
if (valueDeclaration !== undefined) {
checkArrowFunction(node);
}
}
return ts.forEachChild(context.sourceFile, function callback(node) {
if (ts.isCallExpression(node)) {
checkCallExpression(node);
}
return ts.forEachChild(node, callback);
});
}
function isBindPropertyAccess(node) {
return ts.isPropertyAccessExpression(node) && node.name.text === "bind";
}
var templateObject_1;