wallet-core/node_modules/tslint/lib/rules/noUnboundMethodRule.js

"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_1 = require("tsutils");
var ts = require("typescript");
var Lint = require("../index");
var OPTION_IGNORE_STATIC = "ignore-static";
var Rule = /** @class */ (function (_super) {
    tslib_1.__extends(Rule, _super);
    function Rule() {
        return _super !== null && _super.apply(this, arguments) || this;
    }
    Rule.prototype.applyWithProgram = function (sourceFile, program) {
        return this.applyWithFunction(sourceFile, walk, {
            ignoreStatic: this.ruleArguments.indexOf(OPTION_IGNORE_STATIC) !== -1,
        }, program.getTypeChecker());
    };
    /* tslint:disable:object-literal-sort-keys */
    Rule.metadata = {
        ruleName: "no-unbound-method",
        description: "Warns when a method is used outside of a method call.",
        optionsDescription: "You may optionally pass \"" + OPTION_IGNORE_STATIC + "\" to ignore static methods.",
        options: {
            type: "string",
            enum: [OPTION_IGNORE_STATIC],
        },
        optionExamples: [true, [true, OPTION_IGNORE_STATIC]],
        rationale: Lint.Utils.dedent(templateObject_1 || (templateObject_1 = tslib_1.__makeTemplateObject(["\n            Class functions don't preserve the class scope when passed as standalone variables.\n            For example, this code will log the global scope (`window`/`global`), not the class instance:\n\n            ```\n            class MyClass {\n                public log(): void {\n                    console.log(this);\n                }\n            }\n\n            const instance = new MyClass();\n            const log = instance.log;\n\n            log();\n            ```\n\n            You need to either use an arrow lambda (`() => {...}`) or call the function with the correct scope.\n\n            ```\n            class MyClass {\n                public logArrowBound = (): void => {\n                    console.log(bound);\n                };\n\n                public logManualBind(): void {\n                    console.log(this);\n                }\n            }\n\n            const instance = new MyClass();\n            const logArrowBound = instance.logArrowBound;\n            const logManualBind = instance.logManualBind.bind(instance);\n\n            logArrowBound();\n            logManualBind();\n            ```\n        "], ["\n            Class functions don't preserve the class scope when passed as standalone variables.\n            For example, this code will log the global scope (\\`window\\`/\\`global\\`), not the class instance:\n\n            \\`\\`\\`\n            class MyClass {\n                public log(): void {\n                    console.log(this);\n                }\n            }\n\n            const instance = new MyClass();\n            const log = instance.log;\n\n            log();\n            \\`\\`\\`\n\n            You need to either use an arrow lambda (\\`() => {...}\\`) or call the function with the correct scope.\n\n            \\`\\`\\`\n            class MyClass {\n                public logArrowBound = (): void => {\n                    console.log(bound);\n                };\n\n                public logManualBind(): void {\n                    console.log(this);\n                }\n            }\n\n            const instance = new MyClass();\n            const logArrowBound = instance.logArrowBound;\n            const logManualBind = instance.logManualBind.bind(instance);\n\n            logArrowBound();\n            logManualBind();\n            \\`\\`\\`\n        "]))),
        type: "functionality",
        typescriptOnly: true,
        requiresTypeInfo: true,
    };
    /* tslint:enable:object-literal-sort-keys */
    Rule.FAILURE_STRING = "Avoid referencing unbound methods which may cause unintentional scoping of 'this'.";
    return Rule;
}(Lint.Rules.TypedRule));
exports.Rule = Rule;
function walk(ctx, tc) {
    return ts.forEachChild(ctx.sourceFile, function cb(node) {
        if (tsutils_1.isPropertyAccessExpression(node) && !isSafeUse(node)) {
            var symbol = tc.getSymbolAtLocation(node);
            var declaration = symbol === undefined ? undefined : symbol.valueDeclaration;
            if (declaration !== undefined && isMethod(declaration, ctx.options.ignoreStatic)) {
                ctx.addFailureAtNode(node, Rule.FAILURE_STRING);
            }
        }
        return ts.forEachChild(node, cb);
    });
}
function isMethod(node, ignoreStatic) {
    switch (node.kind) {
        case ts.SyntaxKind.MethodDeclaration:
        case ts.SyntaxKind.MethodSignature:
            return !(ignoreStatic && tsutils_1.hasModifier(node.modifiers, ts.SyntaxKind.StaticKeyword));
        default:
            return false;
    }
}
function isSafeUse(node) {
    var parent = node.parent;
    switch (parent.kind) {
        case ts.SyntaxKind.CallExpression:
            return parent.expression === node;
        case ts.SyntaxKind.TaggedTemplateExpression:
            return parent.tag === node;
        // E.g. `obj.method.bind(obj) or obj.method["prop"]`.
        case ts.SyntaxKind.PropertyAccessExpression:
        case ts.SyntaxKind.ElementAccessExpression:
            return true;
        // Allow most binary operators, but don't allow e.g. `myArray.forEach(obj.method || otherObj.otherMethod)`.
        case ts.SyntaxKind.BinaryExpression:
            return parent.operatorToken.kind !== ts.SyntaxKind.BarBarToken;
        case ts.SyntaxKind.NonNullExpression:
        case ts.SyntaxKind.AsExpression:
        case ts.SyntaxKind.TypeAssertionExpression:
        case ts.SyntaxKind.ParenthesizedExpression:
            return isSafeUse(parent);
        // Allow use in conditions
        case ts.SyntaxKind.ConditionalExpression:
            return parent.condition === node;
        case ts.SyntaxKind.IfStatement:
        case ts.SyntaxKind.WhileStatement:
        case ts.SyntaxKind.DoStatement:
        case ts.SyntaxKind.ForStatement:
        case ts.SyntaxKind.PrefixUnaryExpression:
            return true;
        default:
            return false;
    }
}
var templateObject_1;