fix: account for \n and \r in TemplateLiteral handling for the no-useless-mustaches rule (#1040)

Author: baseballyama

.changeset/old-numbers-pull.md

@@ -0,0 +1,5 @@
+---
+'eslint-plugin-svelte': patch
+---
+
+fix: account for \n and \r in `TemplateLiteral` handling for the `no-useless-mustaches` rule

packages/eslint-plugin-svelte/src/rules/no-useless-mustaches.ts

@@ -81,6 +81,10 @@ export default createRule('no-useless-mustaches', {
 				return;
 			}
 
+			if (expression.type === 'TemplateLiteral' && /[\n\r]/.test(rawValue)) {
+				return;
+			}
+
 			let hasEscape = false;
 			if (rawValue !== strValue) {
 				// check escapes

packages/eslint-plugin-svelte/tests/fixtures/rules/no-useless-mustaches/valid/valid-test02-input.svelte

@@ -0,0 +1,5 @@
+<HyperMD
+	value={`# Doc
+
+Text goes here`}
+/>