feat: Add Directive and DirectiveType (#112)

Co-authored-by: Milos Djermanovic <[email protected]>

packages/core/src/types.ts

@@ -419,19 +419,28 @@ export interface CallTraversalStep {
 
 export type TraversalStep = VisitTraversalStep | CallTraversalStep;
 
+/**
+ * The type of disable directive. This determines how ESLint will disable rules.
+ */
+export type DirectiveType =
+	| "disable"
+	| "enable"
+	| "disable-line"
+	| "disable-next-line";
+
 /**
  * Represents a disable directive.
  */
 export interface Directive {
 	/**
 	 * The type of directive.
 	 */
-	type: "disable" | "enable" | "disable-line" | "disable-next-line";
+	type: DirectiveType;
 
 	/**
 	 * The node of the directive. May be in the AST or a comment/token.
 	 */
-	node: object;
+	node: unknown;
 
 	/**
 	 * The value of the directive.

packages/plugin-kit/README.md

@@ -30,6 +30,7 @@ This package exports the following utilities:
 
 -   `ConfigCommentParser` - used to parse ESLint configuration comments (i.e., `/* eslint-disable rule */`)
 -   `VisitNodeStep` and `CallMethodStep` - used to help implement `SourceCode#traverse()`
+-   `Directive` - used to help implement `SourceCode#getDisableDirectives()`
 -   `TextSourceCodeBase` - base class to help implement the `SourceCode` interface
 
 ### `ConfigCommentParser`
@@ -151,6 +152,55 @@ class MySourceCode {
 }
 ```
 
+### `Directive`
+
+The `Directive` class represents a disable directive in the source code and implements the `Directive` interface from `@eslint/core`. You can tell ESLint about disable directives using the `SourceCode#getDisableDirectives()` method, where part of the return value is an array of `Directive` objects. Here's an example:
+
+```js
+import { Directive, ConfigCommentParser } from "@eslint/plugin-kit";
+
+class MySourceCode {
+	getDisableDirectives() {
+		const directives = [];
+		const problems = [];
+		const commentParser = new ConfigCommentParser();
+
+		// read in the inline config nodes to check each one
+		this.getInlineConfigNodes().forEach(comment => {
+			// Step 1: Parse the directive
+			const { label, value, justification } =
+				commentParser.parseDirective(comment.value);
+
+			// Step 2: Extract the directive value and create the `Directive` object
+			switch (label) {
+				case "eslint-disable":
+				case "eslint-enable":
+				case "eslint-disable-next-line":
+				case "eslint-disable-line": {
+					const directiveType = label.slice("eslint-".length);
+
+					directives.push(
+						new Directive({
+							type: directiveType,
+							node: comment,
+							value,
+							justification,
+						}),
+					);
+				}
+
+				// ignore any comments that don't begin with known labels
+			}
+		});
+
+		return {
+			directives,
+			problems,
+		};
+	}
+}
+```
+
 ### `TextSourceCodeBase`
 
 The `TextSourceCodeBase` class is intended to be a base class that has several of the common members found in `SourceCode` objects already implemented. Those members are:

packages/plugin-kit/src/index.js

@@ -8,4 +8,5 @@ export {
 	CallMethodStep,
 	VisitNodeStep,
 	TextSourceCodeBase,
+	Directive,
 } from "./source-code.js";

packages/plugin-kit/src/source-code.js

@@ -16,6 +16,8 @@
 /** @typedef {import("@eslint/core").SourceLocation} SourceLocation */
 /** @typedef {import("@eslint/core").SourceLocationWithOffset} SourceLocationWithOffset */
 /** @typedef {import("@eslint/core").SourceRange} SourceRange */
+/** @typedef {import("@eslint/core").Directive} IDirective */
+/** @typedef {import("@eslint/core").DirectiveType} DirectiveType */
 
 //-----------------------------------------------------------------------------
 // Helpers
@@ -158,6 +160,56 @@ export class CallMethodStep {
 	}
 }
 
+/**
+ * A class to represent a directive comment.
+ * @implements {IDirective}
+ */
+export class Directive {
+	/**
+	 * The type of directive.
+	 * @type {DirectiveType}
+	 * @readonly
+	 */
+	type;
+
+	/**
+	 * The node representing the directive.
+	 * @type {unknown}
+	 * @readonly
+	 */
+	node;
+
+	/**
+	 * Everything after the "eslint-disable" portion of the directive,
+	 * but before the "--" that indicates the justification.
+	 * @type {string}
+	 * @readonly
+	 */
+	value;
+
+	/**
+	 * The justification for the directive.
+	 * @type {string}
+	 * @readonly
+	 */
+	justification;
+
+	/**
+	 * Creates a new instance.
+	 * @param {Object} options The options for the directive.
+	 * @param {"disable"|"enable"|"disable-next-line"|"disable-line"} options.type The type of directive.
+	 * @param {unknown} options.node The node representing the directive.
+	 * @param {string} options.value The value of the directive.
+	 * @param {string} options.justification The justification for the directive.
+	 */
+	constructor({ type, node, value, justification }) {
+		this.type = type;
+		this.node = node;
+		this.value = value;
+		this.justification = justification;
+	}
+}
+
 /**
  * Source Code Base Object
  * @implements {TextSourceCode}

packages/plugin-kit/tests/source-code.test.js

@@ -11,6 +11,7 @@ import assert from "node:assert";
 import {
 	CallMethodStep,
 	VisitNodeStep,
+	Directive,
 	TextSourceCodeBase,
 } from "../src/source-code.js";
 
@@ -63,6 +64,27 @@ describe("source-code", () => {
 		});
 	});
 
+	describe("Directive", () => {
+		it("should create a new instance", () => {
+			const type = "disable";
+			const node = { foo: "bar" };
+			const value = "baz";
+			const justification = "qux";
+
+			const directive = new Directive({
+				type,
+				node,
+				value,
+				justification,
+			});
+
+			assert.strictEqual(directive.type, type);
+			assert.strictEqual(directive.node, node);
+			assert.strictEqual(directive.value, value);
+			assert.strictEqual(directive.justification, justification);
+		});
+	});
+
 	describe("TextSourceCodeBase", () => {
 		describe("new TextSourceCodeBase", () => {
 			it("should create a new instance", () => {