prefer-string-raw: Add support for template literals (#2691)

Co-authored-by: fisker <lionkay@gmail.com>

Author: som-sm

docs/rules/prefer-string-raw.md

@@ -26,3 +26,11 @@ const regexp = new RegExp('foo\\.bar');
 // ✅
 const regexp = new RegExp(String.raw`foo\.bar`);
 ```
+
+```js
+// ❌
+const file = `C:\\windows\\temp\\myapp-${process.pid}.log`;
+
+// ✅
+const file = String.raw`C:\windows\temp\myapp-${process.pid}.log`;
+```

rules/prefer-string-raw.js

@@ -1,5 +1,5 @@
 import {isStringLiteral, isDirective} from './ast/index.js';
-import {fixSpaceAroundKeyword} from './fix/index.js';
+import {fixSpaceAroundKeyword, replaceTemplateElement} from './fix/index.js';
 
 const MESSAGE_ID = 'prefer-string-raw';
 const messages = {
@@ -8,12 +8,8 @@ const messages = {
 
 const BACKSLASH = '\\';
 
-function unescapeBackslash(raw) {
-	const quote = raw.charAt(0);
-
-	return raw
-		.slice(1, -1)
-		.replaceAll(new RegExp(String.raw`\\(?<escapedCharacter>[\\${quote}])`, 'g'), '$<escapedCharacter>');
+function unescapeBackslash(text, quote = '') {
+	return text.replaceAll(new RegExp(String.raw`\\(?<escapedCharacter>[\\${quote}])`, 'g'), '$<escapedCharacter>');
 }
 
 /** @param {import('eslint').Rule.RuleContext} context */
@@ -50,7 +46,7 @@ const create = context => {
 			return;
 		}
 
-		const unescaped = unescapeBackslash(raw);
+		const unescaped = unescapeBackslash(raw.slice(1, -1), raw.charAt(0));
 		if (unescaped !== node.value) {
 			return;
 		}
@@ -59,8 +55,36 @@ const create = context => {
 			node,
 			messageId: MESSAGE_ID,
 			* fix(fixer) {
-				yield fixer.replaceText(node, `String.raw\`${unescaped}\``);
 				yield * fixSpaceAroundKeyword(fixer, node, sourceCode);
+				yield fixer.replaceText(node, `String.raw\`${unescaped}\``);
+			},
+		};
+	});
+
+	context.on('TemplateLiteral', node => {
+		if (
+			(node.parent.type === 'TaggedTemplateExpression' && node.parent.quasi === node)
+			|| node.quasis.every(({value: {cooked, raw}}) => cooked === raw)
+			|| node.quasis.some(({value: {cooked, raw}}) => cooked.at(-1) === BACKSLASH || unescapeBackslash(raw) !== cooked)
+		) {
+			return;
+		}
+
+		return {
+			node,
+			messageId: MESSAGE_ID,
+			* fix(fixer) {
+				yield * fixSpaceAroundKeyword(fixer, node, context.sourceCode);
+				yield fixer.insertTextBefore(node, 'String.raw');
+
+				for (const quasis of node.quasis) {
+					const {cooked, raw} = quasis.value;
+					if (cooked === raw) {
+						continue;
+					}
+
+					yield replaceTemplateElement(fixer, quasis, cooked);
+				}
 			},
 		};
 	});

rules/prefer-string-replace-all.js

@@ -57,11 +57,11 @@ function getPatternReplacement(node) {
 					return String.raw`\t`;
 				}
 
-				return `\\u{${codePoint.toString(16)}}`;
+				return String.raw`\u{${codePoint.toString(16)}}`;
 			}
 
 			if (kind === 'octal') {
-				return `\\u{${codePoint.toString(16)}}`;
+				return String.raw`\u{${codePoint.toString(16)}}`;
 			}
 
 			let character = raw;

test/prefer-string-raw.js

@@ -1,8 +1,10 @@
+/* eslint-disable no-template-curly-in-string */
 import outdent from 'outdent';
 import {getTester} from './utils/test.js';
 
 const {test} = getTester(import.meta);
 
+// String literal to `String.raw`
 test.snapshot({
 	valid: [
 		String.raw`a = '\''`,
@@ -18,7 +20,6 @@ test.snapshot({
 		`,
 		String.raw`a = 'a\\b\u{51}c'`,
 		'a = "a\\\\b`"',
-		// eslint-disable-next-line no-template-curly-in-string
 		'a = "a\\\\b${foo}"',
 		{
 			code: String.raw`<Component attribute="a\\b" />`,
@@ -47,6 +48,55 @@ test.snapshot({
 	],
 });
 
+// `TemplateLiteral` to `String.raw`
+test.snapshot({
+	valid: [
+		// No backslash
+		'a = `a`',
+		'a = `${foo}`',
+		'a = `a${100}b`',
+
+		// Escaped characters other than backslash
+		'a = `a\\t${foo.bar}b\\\\c`', // \t
+		'a = `${foo}\\\\a${bar}\\``', // \`
+		'a = `a\\${`', // \$
+		'a = `a$\\{`', // \{
+		'a = `${a}\\\'${b}\\\\`', // \'
+		'a = `\\"a\\\\b`', // \"
+
+		// Ending with backslash
+		'a = `\\\\a${foo}b\\\\${foo}`',
+
+		// Tagged template expression
+		'a = String.raw`a\\\\b`',
+
+		// Slash before newline (spread into multiple lines)
+		outdent`
+			a = \`\\\\a \\
+			b\`
+		`,
+	],
+	invalid: [
+		'a = `a\\\\b`',
+		'function a() {return`a\\\\b${foo}cd`}',
+		'a = {[`a\\\\b${foo}cd${foo.bar}e\\\\f`]: b}',
+		'a = `a${foo}${foo.bar}b\\\\c`',
+		'a = `a\\\\b${"c\\\\d"}e`',
+		outdent`
+			a = \`\\\\a
+			b\`
+		`,
+		outdent`
+			a = \`\\\\a\${foo}
+			b\${bar}c
+			d\\\\\\\\e\`
+		`,
+		'a = `a\\\\b${ foo /* bar */}c\\\\d`',
+		'a = `a\\\\b${ foo + bar }`',
+		'a = `${ foo .bar }a\\\\b`',
+	],
+});
+
 test.typescript({
 	valid: [
 		outdent`