fix(javascript): resolve root package exports arrays (#1046)

Co-authored-by: N0zoM1z0 <1705004398@qq.com>

docs/javascript-artifact-reconstruction.md

@@ -226,3 +226,7 @@ URI schemes are classified independently of local file names: a reference such
 as `web3:app.js` remains external even when an artifact has that literal name.
 Scheme characters may include digits after the initial letter; a relative path
 such as `./web3:app.js` still names a local artifact.
+
+Package `exports` fallback arrays are supported both at the top level and under
+the root `"."` entry. The resolver selects targets in declared order using the
+same conditional and invalid-entry handling as nested exports arrays.

src/application/javascript/JavaScriptArtifactPathResolution.ts

@@ -440,12 +440,10 @@ const packageExport = (
   moduleKind: ResolveArtifactPathInput["moduleKind"],
 ): PackageExportOutcome => {
   if (typeof value === "string") return packagePathValue(value);
-  if (typeof value !== "object" || value === null || Array.isArray(value))
-    return { status: "invalid" };
+  if (typeof value !== "object" || value === null) return { status: "invalid" };
   const root = Reflect.get(value, ".") ?? value;
   if (typeof root === "string") return packagePathValue(root);
-  if (typeof root !== "object" || root === null || Array.isArray(root))
-    return { status: "invalid" };
+  if (typeof root !== "object" || root === null) return { status: "invalid" };
   const flattened = exportTargets(root, packageExportConditions(moduleKind));
   if (flattened.kind === "invalid") return { status: "invalid" };
   const first =

tests/boundary/filesystem/javascriptPackagePrecedence.test.ts

@@ -25,6 +25,26 @@ const cases: readonly {
     metadata: { main: "actual.cjs" },
     index: false,
   },
+  {
+    name: "top-level exports array",
+    metadata: { exports: ["./actual.cjs"] },
+    index: true,
+  },
+  {
+    name: "root subpath exports array",
+    metadata: { exports: { ".": ["./actual.cjs"] } },
+    index: true,
+  },
+  {
+    name: "exports array skips invalid and unmatched entries",
+    metadata: { exports: [42, { browser: "./browser.js" }, "./actual.cjs"] },
+    index: true,
+  },
+  {
+    name: "nested root exports array",
+    metadata: { exports: { ".": [[null, { require: "./actual.cjs" }]] } },
+    index: true,
+  },
   { name: "index fallback", metadata: {}, index: true },
   {
     name: "missing legacy main fallback",