chore: migrate eslint config and fix lint errors

Author: rzhao271

.eslintrc.json

@@ -0,0 +1,38 @@
+/* eslint-disable no-undef */
+const js = require("@eslint/js");
+const tseslint = require("@typescript-eslint/eslint-plugin");
+const tsParser = require("@typescript-eslint/parser");
+
+/** @type {import("eslint").Linter.Config[]} */
+module.exports = [
+    js.configs.recommended,
+    {
+        files: ["**/*.ts", "**/*.tsx"],
+        languageOptions: {
+            parser: tsParser,
+            parserOptions: {
+                ecmaVersion: 6,
+                sourceType: "module",
+            },
+        },
+        plugins: {
+            "@typescript-eslint": tseslint,
+        },
+        rules: {
+            "@typescript-eslint/naming-convention": [
+                "warn",
+                {
+                    selector: "typeLike",
+                    format: ["PascalCase"],
+                },
+            ],
+            curly: "warn",
+            eqeqeq: "warn",
+            "no-throw-literal": "warn",
+            semi: "warn",
+            "no-unused-expressions": "warn",
+            "no-duplicate-imports": "warn",
+            "new-parens": "warn",
+        },
+    },
+];

eslint.config.js

@@ -19,7 +19,7 @@ import {
 	SyntaxKind
 } from '../main';
 
-namespace ParseOptions {
+namespace ParseOptionsConfigs {
 	export const DEFAULT = {
 		allowTrailingComma: false
 	};
@@ -61,7 +61,7 @@ export function getLocation(text: string, position: number): Location {
 	try {
 
 		visit(text, {
-			onObjectBegin: (offset: number, length: number) => {
+			onObjectBegin: (offset: number) => {
 				if (position <= offset) {
 					throw earlyReturnException;
 				}
@@ -79,21 +79,21 @@ export function getLocation(text: string, position: number): Location {
 					throw earlyReturnException;
 				}
 			},
-			onObjectEnd: (offset: number, length: number) => {
+			onObjectEnd: (offset: number) => {
 				if (position <= offset) {
 					throw earlyReturnException;
 				}
 				previousNode = undefined;
 				segments.pop();
 			},
-			onArrayBegin: (offset: number, length: number) => {
+			onArrayBegin: (offset: number) => {
 				if (position <= offset) {
 					throw earlyReturnException;
 				}
 				previousNode = undefined;
 				segments.push(0);
 			},
-			onArrayEnd: (offset: number, length: number) => {
+			onArrayEnd: (offset: number) => {
 				if (position <= offset) {
 					throw earlyReturnException;
 				}
@@ -110,7 +110,7 @@ export function getLocation(text: string, position: number): Location {
 					throw earlyReturnException;
 				}
 			},
-			onSeparator: (sep: string, offset: number, length: number) => {
+			onSeparator: (sep: string, offset: number) => {
 				if (position <= offset) {
 					throw earlyReturnException;
 				}
@@ -159,7 +159,7 @@ export function getLocation(text: string, position: number): Location {
  * Parses the given text and returns the object the JSON content represents. On invalid input, the parser tries to be as fault tolerant as possible, but still return a result.
  * Therefore always check the errors list to find out if the input was valid.
  */
-export function parse(text: string, errors: ParseError[] = [], options: ParseOptions = ParseOptions.DEFAULT): any {
+export function parse(text: string, errors: ParseError[] = [], options: ParseOptions = ParseOptionsConfigs.DEFAULT): any {
 	let currentProperty: string | null = null;
 	let currentParent: any = [];
 	const previousParents: any[] = [];
@@ -209,7 +209,7 @@ export function parse(text: string, errors: ParseError[] = [], options: ParseOpt
 /**
  * Parses the given text and returns a tree representation the JSON content. On invalid input, the parser tries to be as fault tolerant as possible, but still return a result.
  */
-export function parseTree(text: string, errors: ParseError[] = [], options: ParseOptions = ParseOptions.DEFAULT): Node | undefined {
+export function parseTree(text: string, errors: ParseError[] = [], options: ParseOptions = ParseOptionsConfigs.DEFAULT): Node | undefined {
 	let currentParent: NodeImpl = { type: 'array', offset: -1, length: -1, children: [], parent: undefined }; // artificial root
 
 	function ensurePropertyComplete(endOffset: number) {
@@ -239,7 +239,7 @@ export function parseTree(text: string, errors: ParseError[] = [], options: Pars
 			currentParent = currentParent.parent!;
 			ensurePropertyComplete(offset + length);
 		},
-		onArrayBegin: (offset: number, length: number) => {
+		onArrayBegin: (offset: number) => {
 			currentParent = onValue({ type: 'array', offset, length: -1, parent: currentParent, children: [] });
 		},
 		onArrayEnd: (offset: number, length: number) => {
@@ -251,7 +251,7 @@ export function parseTree(text: string, errors: ParseError[] = [], options: Pars
 			onValue({ type: getNodeType(value), offset, length, parent: currentParent, value });
 			ensurePropertyComplete(offset + length);
 		},
-		onSeparator: (sep: string, offset: number, length: number) => {
+		onSeparator: (sep: string, offset: number) => {
 			if (currentParent.type === 'property') {
 				if (sep === ':') {
 					currentParent.colonOffset = offset;
@@ -335,7 +335,7 @@ export function getNodeValue(node: Node): any {
 	switch (node.type) {
 		case 'array':
 			return node.children!.map(getNodeValue);
-		case 'object':
+		case 'object': {
 			const obj = Object.create(null);
 			for (let prop of node.children!) {
 				const valueNode = prop.children![1];
@@ -344,6 +344,7 @@ export function getNodeValue(node: Node): any {
 				}
 			}
 			return obj;
+		}
 		case 'null':
 		case 'string':
 		case 'number':
@@ -383,7 +384,7 @@ export function findNodeAtOffset(node: Node, offset: number, includeRightBound =
 /**
  * Parses the given text and invokes the visitor functions for each object, array and literal reached.
  */
-export function visit(text: string, visitor: JSONVisitor, options: ParseOptions = ParseOptions.DEFAULT): any {
+export function visit(text: string, visitor: JSONVisitor, options: ParseOptions = ParseOptionsConfigs.DEFAULT): any {
 
 	const _scanner = createScanner(text, false);
 	// Important: Only pass copies of this to visitor functions to prevent accidental modification, and
@@ -512,16 +513,17 @@ export function visit(text: string, visitor: JSONVisitor, options: ParseOptions
 
 	function parseLiteral(): boolean {
 		switch (_scanner.getToken()) {
-			case SyntaxKind.NumericLiteral:
-				const tokenValue = _scanner.getTokenValue();
-				let value = Number(tokenValue);
+			case SyntaxKind.NumericLiteral: {
+					const tokenValue = _scanner.getTokenValue();
+					let value = Number(tokenValue);
 
-				if (isNaN(value)) {
-					handleError(ParseErrorCode.InvalidNumberFormat);
-					value = 0;
-				}
+					if (isNaN(value)) {
+						handleError(ParseErrorCode.InvalidNumberFormat);
+						value = 0;
+					}
 
-				onLiteralValue(value);
+					onLiteralValue(value);
+				}
 				break;
 			case SyntaxKind.NullKeyword:
 				onLiteralValue(null);

src/impl/parser.ts

@@ -125,7 +125,7 @@ export function createScanner(text: string, ignoreTrivia: boolean = false): JSON
 				const ch2 = text.charCodeAt(pos++);
 				switch (ch2) {
 					case CharacterCodes.doubleQuote:
-						result += '\"';
+						result += '"';
 						break;
 					case CharacterCodes.backslash:
 						result += '\\';
@@ -148,12 +148,13 @@ export function createScanner(text: string, ignoreTrivia: boolean = false): JSON
 					case CharacterCodes.t:
 						result += '\t';
 						break;
-					case CharacterCodes.u:
-						const ch3 = scanHexDigits(4, true);
-						if (ch3 >= 0) {
-							result += String.fromCharCode(ch3);
-						} else {
-							scanError = ScanError.InvalidUnicode;
+					case CharacterCodes.u: {
+							const ch3 = scanHexDigits(4, true);
+							if (ch3 >= 0) {
+								result += String.fromCharCode(ch3);
+							} else {
+								scanError = ScanError.InvalidUnicode;
+							}
 						}
 						break;
 					default:
@@ -245,7 +246,7 @@ export function createScanner(text: string, ignoreTrivia: boolean = false): JSON
 				return token = SyntaxKind.StringLiteral;
 
 			// comments
-			case CharacterCodes.slash:
+			case CharacterCodes.slash: {
 				const start = pos - 1;
 				// Single-line comment
 				if (text.charCodeAt(pos + 1) === CharacterCodes.slash) {
@@ -301,6 +302,7 @@ export function createScanner(text: string, ignoreTrivia: boolean = false): JSON
 				value += String.fromCharCode(code);
 				pos++;
 				return token = SyntaxKind.Unknown;
+			}
 
 			// numbers
 			case CharacterCodes.minus:
@@ -312,6 +314,7 @@ export function createScanner(text: string, ignoreTrivia: boolean = false): JSON
 			// found a minus, followed by a number so
 			// we fall through to proceed with scanning
 			// numbers
+			// eslint-disable-next-line no-fallthrough
 			case CharacterCodes._0:
 			case CharacterCodes._1:
 			case CharacterCodes._2:

src/impl/scanner.ts

@@ -5,7 +5,8 @@
 'use strict';
 
 import * as assert from 'assert';
-import { FormattingOptions, Edit, ModificationOptions, modify } from '../main';
+import { suite, test } from 'mocha';
+import { Edit, FormattingOptions, ModificationOptions, modify } from '../main';
 
 suite('JSON - edits', () => {
 
@@ -30,21 +31,10 @@ suite('JSON - edits', () => {
 		keepLines: false
 	};
 
-	let formattingOptionsKeepLines: FormattingOptions = {
-		insertSpaces: true,
-		tabSize: 2,
-		eol: '\n',
-		keepLines: true
-	};
-
 	let options: ModificationOptions = {
 		formattingOptions
 	};
 
-	let optionsKeepLines: ModificationOptions = {
-		formattingOptions : formattingOptionsKeepLines
-	};
-
 	test('set property', () => {
 		let content = '{\n  "x": "y"\n}';
 		let edits = modify(content, ['x'], 'bar', options);

src/test/edit.test.ts

@@ -5,6 +5,7 @@
 'use strict';
 
 import * as assert from 'assert';
+import { suite, test } from 'mocha';
 import * as Formatter from '../impl/format';
 import { Range } from '../main';
 
@@ -21,14 +22,8 @@ suite('JSON - formatter', () => {
 
 		const edits = Formatter.format(content, range, { tabSize: 2, insertSpaces, insertFinalNewline, eol: '\n', keepLines });
 
-		let lastEditOffset = content.length;
-
 		for (let i = edits.length - 1; i >= 0; i--) {
 			const edit = edits[i];
-			// assert(edit.offset >= 0 && edit.length >= 0 && edit.offset + edit.length <= content.length);
-			// assert(typeof edit.content === 'string');
-			// assert(lastEditOffset >= edit.offset + edit.length); // make sure all edits are ordered
-			lastEditOffset = edit.offset;
 			content = content.substring(0, edit.offset) + edit.content + content.substring(edit.offset + edit.length);
 		}
 

src/test/format.test.ts

@@ -5,6 +5,7 @@
 'use strict';
 
 import * as assert from 'assert';
+import { suite, test } from 'mocha';
 import {
 	SyntaxKind, createScanner, parse, getLocation, Node, ParseError, parseTree, ParseErrorCode,
 	ParseOptions, Segment, findNodeAtLocation, getNodeValue, getNodePath, ScanError, visit, JSONVisitor, JSONPath

src/test/json.test.ts

@@ -1,5 +1,6 @@
-import { cachedBreakLinesWithSpaces, cachedSpaces, supportedEols } from '../impl/string-intern';
 import * as assert from 'assert';
+import { suite, test } from 'mocha';
+import { cachedBreakLinesWithSpaces, cachedSpaces, supportedEols } from '../impl/string-intern';
 
 suite('string intern', () => {
   test('should correctly define spaces intern', () => {