prefer-export-from: Support import assertions (#1618)

rules/prefer-export-from.js

@@ -74,6 +74,16 @@ function * removeImportOrExport(node, fixer, sourceCode) {
 	}
 }
 
+function getSourceAndAssertionsText(declaration, sourceCode) {
+	const keywordFromToken = sourceCode.getTokenBefore(
+		declaration.source,
+		token => token.type === 'Identifier' && token.value === 'from',
+	);
+	const [start] = keywordFromToken.range;
+	const [, end] = declaration.range;
+	return sourceCode.text.slice(start, end);
+}
+
 function getFixFunction({
 	context,
 	imported,
@@ -82,17 +92,17 @@ function getFixFunction({
 	program,
 }) {
 	const sourceCode = context.getSourceCode();
-	const sourceNode = imported.declaration.source;
+	const importDeclaration = imported.declaration;
+	const sourceNode = importDeclaration.source;
 	const sourceValue = sourceNode.value;
-	const sourceText = sourceCode.getText(sourceNode);
 	const exportDeclaration = exportDeclarations.find(({source}) => source.value === sourceValue);
 
 	/** @param {import('eslint').Rule.RuleFixer} fixer */
 	return function * (fixer) {
 		if (imported.name === '*') {
 			yield fixer.insertTextAfter(
 				program,
-				`\nexport * as ${exported.name} from ${sourceText};`,
+				`\nexport * as ${exported.name} ${getSourceAndAssertionsText(importDeclaration, sourceCode)}`,
 			);
 		} else {
 			const specifier = exported.name === imported.name
@@ -112,7 +122,7 @@ function getFixFunction({
 			} else {
 				yield fixer.insertTextAfter(
 					program,
-					`\nexport {${specifier}} from ${sourceText};`,
+					`\nexport {${specifier}} ${getSourceAndAssertionsText(importDeclaration, sourceCode)}`,
 				);
 			}
 		}

test/prefer-export-from.mjs

@@ -394,3 +394,65 @@ test.snapshot({
 		`,
 	].map(code => ({code, options: [{ignoreUsedVariables: true}]})),
 });
+
+// TODO: Run test with default parser when it support "import assertions"
+test.babel({
+	testerOptions: {
+		parserOptions: {
+			babelOptions: {
+				parserOpts: {
+					plugins: ['importAssertions'],
+				},
+			},
+		},
+	},
+	valid: [],
+	invalid: [
+		{
+			code: outdent`
+				import json from './foo.json' assert { type: 'json' };
+				export default json;
+			`,
+			errors: 1,
+			output: outdent`
+				\n
+				export {default} from './foo.json' assert { type: 'json' };
+			`,
+		},
+		{
+			code: outdent`
+				import * as json from './foo.json' assert { type: 'json' };
+				export {json};
+			`,
+			errors: 1,
+			output: outdent`
+				\n
+				export * as json from './foo.json' assert { type: 'json' };
+			`,
+		},
+		{
+			code: outdent`
+				import {foo} from './foo.json' assert { type: 'json' };
+				export {foo};
+				export {bar} from './foo.json';
+			`,
+			errors: 1,
+			output: outdent`
+				\n
+				export {bar, foo} from './foo.json';
+			`,
+		},
+		{
+			code: outdent`
+				import {foo} from './foo.json';
+				export {foo};
+				export {bar} from './foo.json' assert { type: 'json' };
+			`,
+			errors: 1,
+			output: outdent`
+				\n
+				export {bar, foo} from './foo.json' assert { type: 'json' };
+			`,
+		},
+	],
+});