feat(FN-5059): merge fusion/fn-5059

packages/core/src/__tests__/index-exports.test.ts

@@ -0,0 +1,31 @@
+import { readFileSync } from "node:fs";
+import { resolve } from "node:path";
+import { describe, expect, it } from "vitest";
+
+describe("FN-5059 core index exports", () => {
+  it("prevents duplicate export specifiers across export-from blocks", () => {
+    const indexPath = resolve(import.meta.dirname, "..", "index.ts");
+    const source = readFileSync(indexPath, "utf8");
+
+    const exportFromBlock = /export\s*\{([\s\S]*?)\}\s*from\s*["'][^"']+["'];/g;
+    const counts = new Map<string, number>();
+
+    for (const match of source.matchAll(exportFromBlock)) {
+      const specifierBlock = match[1] ?? "";
+      for (const rawSpecifier of specifierBlock.split(",")) {
+        const specifier = rawSpecifier.trim();
+        if (!specifier) continue;
+
+        const withoutType = specifier.replace(/^type\s+/, "");
+        const exportedName = withoutType.includes(" as ")
+          ? withoutType.split(/\s+as\s+/)[1]?.trim() ?? withoutType
+          : withoutType;
+
+        counts.set(exportedName, (counts.get(exportedName) ?? 0) + 1);
+      }
+    }
+
+    const duplicates = [...counts.entries()].filter(([, count]) => count > 1);
+    expect(duplicates).toEqual([]);
+  });
+});