fix: avoid false positive in no-unassigned-vars for declare module

azat-io · azat-io · commit b92efb319fe7 · 2025-05-19T21:18:48.000+03:00
diff --git a/lib/rules/no-unassigned-vars.js b/lib/rules/no-unassigned-vars.js
@@ -36,12 +36,19 @@ module.exports = {
 			VariableDeclarator(node) {
 				/** @type {import('estree').VariableDeclaration} */
 				const declaration = node.parent;
-				const shouldCheck =
-					!node.init &&
-					node.id.type === "Identifier" &&
-					declaration.kind !== "const" &&
-					!declaration.declare;
-				if (!shouldCheck) {
+				const ancestors = context.sourceCode.getAncestors(node);
+				const insideDeclareModule = ancestors.some(
+					ancestorNode =>
+						ancestorNode.type === "TSModuleDeclaration" &&
+						ancestorNode.declare === true
+				);
+				const shouldSkip =
+					node.init ||
+					node.id.type !== "Identifier" ||
+					declaration.kind === "const" ||
+					declaration.declare ||
+					insideDeclareModule;
+				if (shouldSkip) {
 					return;
 				}
 				const [variable] = sourceCode.getDeclaredVariables(node);
diff --git a/tests/lib/rules/no-unassigned-vars.js b/tests/lib/rules/no-unassigned-vars.js
@@ -140,6 +140,13 @@ ruleTesterTypeScript.run("no-unassigned-vars", rule, {
 				}
 			}
 		`,
+		unIndent`
+			declare module 'module' {
+				import type { T } from 'module'
+				let x: T
+				export = x
+			}
+		`,
 	],
 	invalid: [
 		{

Original file line number	Diff line number	Diff line change
`@@ -140,6 +140,13 @@ ruleTesterTypeScript.run("no-unassigned-vars", rule, {`
`140`	`140`	`}`
`141`	`141`	`}`
`142`	`142`	`,
	`143`	+ unIndent`
	`144`	`+ declare module 'module' {`
	`145`	`+ import type { T } from 'module'`
	`146`	`+ let x: T`
	`147`	`+ export = x`
	`148`	`+ }`
	`149`	+ `,
`143`	`150`	`],`
`144`	`151`	`invalid: [`
`145`	`152`	`{`