TypeScript/scripts/tslint/noInOperatorRule.ts

19 lines
718 B
TypeScript

import * as Lint from "tslint/lib";
import * as ts from "typescript";
export class Rule extends Lint.Rules.AbstractRule {
public static FAILURE_STRING = "Don't use the 'in' keyword - use 'hasProperty' to check for key presence instead";
public apply(sourceFile: ts.SourceFile): Lint.RuleFailure[] {
return this.applyWithFunction(sourceFile, walk);
}
}
function walk(ctx: Lint.WalkContext<void>): void {
ts.forEachChild(ctx.sourceFile, recur);
function recur(node: ts.Node): void {
if (node.kind === ts.SyntaxKind.InKeyword && node.parent.kind === ts.SyntaxKind.BinaryExpression) {
ctx.addFailureAtNode(node, Rule.FAILURE_STRING);
}
}
}