捕获“==未定义”的自定义tslint规则不起作用

我抄了 this tslint rule 在我的项目中工作,所以现在tslint === null 使它成为一个错误。

我现在想做同样的事,但是为了 undefined . 我已经实现了和 null 但换了张支票 ts.SyntaxKind.UndefinedKeyWord 而不是 ts.SyntaxKind.NullKeyword 但不知什么原因 === undefined .

如果它和 无效的 一个在工作?

notripleequalsnullrule.ts号

import * as ts from "typescript";
import * as Lint from "tslint";

const OPTION_NO_NULL_KEYWORD = "no-null-keyword";

export class Rule extends Lint.Rules.AbstractRule {
    public static EQ_FAILURE_STRING = "Did you mean == null instead?";
    public static NEQ_FAILURE_STRING = "Did you mean != null instead?";

    public apply(sourceFile: ts.SourceFile): Lint.RuleFailure[] {
        const noTripleEqualsNullWalker = new NoTripleEqualsNullWalker(sourceFile, this.getOptions());
        return this.applyWithWalker(noTripleEqualsNullWalker);
    }
}

class NoTripleEqualsNullWalker extends Lint.RuleWalker {
    public visitBinaryExpression(node: ts.BinaryExpression) {
        if (this.isExpressionAllowed(node)) {
            const position = node.getChildAt(1).getStart();
            const expressionWidth = node.right.getFullWidth() + 3;
            this.handleBinaryComparison(position, expressionWidth, node.operatorToken.kind, node.right.kind);
        }

        super.visitBinaryExpression(node);
    }

    private handleBinaryComparison(position: number, expressionWidth: number, operator: ts.SyntaxKind, right: ts.SyntaxKind) {
        switch (operator) {
            case ts.SyntaxKind.EqualsEqualsEqualsToken:
                if (right === ts.SyntaxKind.NullKeyword) {
                    this.addFailure(this.createFailure(position, expressionWidth, Rule.EQ_FAILURE_STRING));
                }
                break;
            case ts.SyntaxKind.ExclamationEqualsEqualsToken:
                if (right === ts.SyntaxKind.NullKeyword) {
                    this.addFailure(this.createFailure(position, expressionWidth, Rule.NEQ_FAILURE_STRING));
                }
                break;
            default:
                break;
        }
    }

    private isExpressionAllowed(node: ts.BinaryExpression) {
        const nullKeyword = ts.SyntaxKind.NullKeyword;

        return !this.hasOption(OPTION_NO_NULL_KEYWORD)
            && (node.left.kind ===  nullKeyword || node.right.kind === nullKeyword);
    }
}

不可抗力

import * as ts from "typescript";
import * as Lint from "tslint";

const OPTION_NO_NULL_KEYWORD = "no-null-keyword";

export class Rule extends Lint.Rules.AbstractRule {
    public static EQ_FAILURE_STRING = "Did you mean == null instead?";
    public static NEQ_FAILURE_STRING = "Did you mean != null instead?";

    public apply(sourceFile: ts.SourceFile): Lint.RuleFailure[] {
        const noTripleEqualsNullWalker = new NoTripleEqualsNullWalker(sourceFile, this.getOptions());
        return this.applyWithWalker(noTripleEqualsNullWalker);
    }
}

class NoTripleEqualsNullWalker extends Lint.RuleWalker {
    public visitBinaryExpression(node: ts.BinaryExpression) {
        if (this.isExpressionAllowed(node)) {
            const position = node.getChildAt(1).getStart();
            const expressionWidth = node.right.getFullWidth() + 3;
            this.handleBinaryComparison(position, expressionWidth, node.operatorToken.kind, node.right.kind);
        }

        super.visitBinaryExpression(node);
    }

    private handleBinaryComparison(position: number, expressionWidth: number, operator: ts.SyntaxKind, right: ts.SyntaxKind) {
        switch (operator) {
            case ts.SyntaxKind.EqualsEqualsEqualsToken:
                if (right === ts.SyntaxKind.UndefinedKeyword) {
                    this.addFailure(this.createFailure(position, expressionWidth, Rule.EQ_FAILURE_STRING));
                }
                break;
            case ts.SyntaxKind.ExclamationEqualsEqualsToken:
                if (right === ts.SyntaxKind.UndefinedKeyword) {
                    this.addFailure(this.createFailure(position, expressionWidth, Rule.NEQ_FAILURE_STRING));
                }
                break;
            default:
                break;
        }
    }

    private isExpressionAllowed(node: ts.BinaryExpression) {
        const nullKeyword = ts.SyntaxKind.UndefinedKeyword;

        return !this.hasOption(OPTION_NO_NULL_KEYWORD)
            && (node.left.kind ===  nullKeyword || node.right.kind === nullKeyword);
    }
}