prefer-export-from: Fix crash in TypeScript files (#1647)

sindresorhus · Dec 20, 2021 · 1ff8e42 · 1ff8e42
1 parent e59a856
commit 1ff8e42
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Showing 2 changed files with 36 additions and 11 deletions.
diff --git a/rules/prefer-export-from.js b/rules/prefer-export-from.js
@@ -207,7 +207,7 @@ function isVariableUnused(node, context) {
 }
 
 function getImported(variable, sourceCode) {
-	const specifier = variable.identifiers[0].parent;
+	const specifier = variable.defs[0].node;
 	const result = {
 		node: specifier,
 		declaration: specifier.parent,
@@ -297,17 +297,22 @@ function create(context) {
 		},
 		* 'Program:exit'(program) {
 			for (const importDeclaration of importDeclarations) {
-				const variables = context.getDeclaredVariables(importDeclaration)
-					.map(variable => {
-						const imported = getImported(variable, sourceCode);
-						const exports = getExports(imported, context, sourceCode);
+				let variables = context.getDeclaredVariables(importDeclaration);
 
-						return {
-							variable,
-							imported,
-							exports,
-						};
-					});
+				if (variables.some(variable => variable.defs.length !== 1 || variable.defs[0].parent !== importDeclaration)) {
+					continue;
+				}
+
+				variables = variables.map(variable => {
+					const imported = getImported(variable, sourceCode);
+					const exports = getExports(imported, context, sourceCode);
+
+					return {
+						variable,
+						imported,
+						exports,
+					};
+				});
 
 				if (
 					ignoreUsedVariables

diff --git a/test/prefer-export-from.mjs b/test/prefer-export-from.mjs
@@ -330,6 +330,26 @@ test.typescript({
 
 			export const useDispatch: () => DispatchAllActions = reduxUseDispatch
 		`,
+		// #1645
+		outdent`
+			import React from "react";
+			import React from "react";
+			export {React}
+		`,
+		outdent`
+			type AceEditor = import("ace-builds").Ace.Editor;
+			import AceEditor from "./advanced-editor";
+		`,
+		outdent`
+			type AceEditor = import("ace-builds").Ace.Editor;
+			import AceEditor from "./advanced-editor";
+			export {AceEditor};
+		`,
+		outdent`
+			import AceEditor from "./advanced-editor";
+			type AceEditor = import("ace-builds").Ace.Editor;
+			export {AceEditor};
+		`,
 	],
 	invalid: [],
 });