fix(shadcn): fix async imports not being transformed (#8036)

* fix(shadcn): fix async imports not being transformed when installing components

* fix(shadcn): improve performance

* test(shadcn): add tests for transform import

* test: update timeout

---------

Co-authored-by: shadcn <m@shadcn.com>

Author: fuma-nama

.changeset/tame-schools-flow.md

@@ -0,0 +1,5 @@
+---
+"shadcn": patch
+---
+
+fix async imports not being transformed when installing components

packages/shadcn/src/utils/transformers/transform-import.ts

@@ -1,5 +1,6 @@
 import { Config } from "@/src/utils/get-config"
 import { Transformer } from "@/src/utils/transformers"
+import { SyntaxKind } from "ts-morph"
 
 export const transformImport: Transformer = async ({
   sourceFile,
@@ -9,32 +10,34 @@ export const transformImport: Transformer = async ({
   const workspaceAlias = config.aliases?.utils?.split("/")[0]?.slice(1)
   const utilsImport = `@${workspaceAlias}/lib/utils`
 
-  const importDeclarations = sourceFile.getImportDeclarations()
-
   if (![".tsx", ".ts", ".jsx", ".js"].includes(sourceFile.getExtension())) {
     return sourceFile
   }
 
-  for (const importDeclaration of importDeclarations) {
-    const moduleSpecifier = updateImportAliases(
-      importDeclaration.getModuleSpecifierValue(),
+  for (const specifier of sourceFile.getImportStringLiterals()) {
+    const updated = updateImportAliases(
+      specifier.getLiteralValue(),
       config,
       isRemote
     )
-
-    importDeclaration.setModuleSpecifier(moduleSpecifier)
+    specifier.setLiteralValue(updated)
 
     // Replace `import { cn } from "@/lib/utils"`
-    if (utilsImport === moduleSpecifier || moduleSpecifier === "@/lib/utils") {
-      const namedImports = importDeclaration.getNamedImports()
-      const cnImport = namedImports.find((i) => i.getName() === "cn")
-      if (cnImport) {
-        importDeclaration.setModuleSpecifier(
-          utilsImport === moduleSpecifier
-            ? moduleSpecifier.replace(utilsImport, config.aliases.utils)
-            : config.aliases.utils
-        )
-      }
+    if (utilsImport === updated || updated === "@/lib/utils") {
+      const importDeclaration = specifier.getFirstAncestorByKind(
+        SyntaxKind.ImportDeclaration
+      )
+      const isCnImport = importDeclaration
+        ?.getNamedImports()
+        .some((namedImport) => namedImport.getName() === "cn")
+
+      if (!isCnImport) continue
+
+      specifier.setLiteralValue(
+        utilsImport === updated
+          ? updated.replace(utilsImport, config.aliases.utils)
+          : config.aliases.utils
+      )
     }
   }
 

packages/shadcn/test/utils/__snapshots__/transform-import.test.ts.snap

@@ -1,5 +1,57 @@
 // Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
 
+exports[`transform async/dynamic imports 1`] = `
+"import * as React from "react"
+import { Button } from "@/components/ui/button"
+
+async function loadComponent() {
+  const { cn } = await import("@/lib/utils")
+  const module = await import("@/components/ui/card")
+  return module
+}
+
+function lazyLoad() {
+  return import("@/components/ui/dialog").then(module => module)
+}
+    "
+`;
+
+exports[`transform async/dynamic imports 2`] = `
+"import { Button } from "~/components/ui/button"
+
+async function loadUtils() {
+  const utils = await import("~/lib/utils")
+  const { cn } = await import("~/lib/utils")
+  return { utils, cn }
+}
+
+const dialogPromise = import("~/components/ui/dialog")
+const cardModule = import("~/components/ui/card")
+    "
+`;
+
+exports[`transform dynamic imports with cn utility 1`] = `
+"async function loadCn() {
+  const { cn } = await import("@/lib/utils")
+  return cn
+}
+
+async function loadMultiple() {
+  const utils1 = await import("@/lib/utils")
+  const { cn, twMerge } = await import("@/lib/utils")
+  const other = await import("@/lib/other")
+}
+    "
+`;
+
+exports[`transform dynamic imports with cn utility 2`] = `
+"async function loadWorkspaceCn() {
+  const { cn } = await import("@workspace/lib/utils")
+  return cn
+}
+    "
+`;
+
 exports[`transform import 1`] = `
 "import * as React from "react"
 import { Foo } from "bar"
@@ -91,3 +143,14 @@ import { Foo } from "bar"
     import { cn } from "@repo/ui/lib/utils"
     "
 `;
+
+exports[`transform re-exports with dynamic imports 1`] = `
+"export { cn } from "@/lib/utils"
+export { Button } from "@/components/ui/button"
+
+async function load() {
+  const module = await import("@/components/ui/card")
+  return module
+}
+    "
+`;

packages/shadcn/test/utils/transform-import.test.ts

@@ -144,7 +144,6 @@ import { Foo } from "bar"
   ).toMatchSnapshot()
 })
 
-
 test("transform import for monorepo", async () => {
   expect(
     await transform({
@@ -196,3 +195,122 @@ import { Foo } from "bar"
     })
   ).toMatchSnapshot()
 })
+
+test("transform async/dynamic imports", async () => {
+  expect(
+    await transform({
+      filename: "test.ts",
+      raw: `import * as React from "react"
+import { Button } from "@/registry/new-york/ui/button"
+
+async function loadComponent() {
+  const { cn } = await import("@/lib/utils")
+  const module = await import("@/registry/new-york/ui/card")
+  return module
+}
+
+function lazyLoad() {
+  return import("@/registry/new-york/ui/dialog").then(module => module)
+}
+    `,
+      config: {
+        tsx: true,
+        aliases: {
+          components: "@/components",
+          utils: "@/lib/utils",
+        },
+      },
+    })
+  ).toMatchSnapshot()
+
+  expect(
+    await transform({
+      filename: "test.ts",
+      raw: `import { Button } from "@/registry/new-york/ui/button"
+
+async function loadUtils() {
+  const utils = await import("@/lib/utils")
+  const { cn } = await import("@/lib/utils")
+  return { utils, cn }
+}
+
+const dialogPromise = import("@/registry/new-york/ui/dialog")
+const cardModule = import("@/registry/new-york/ui/card")
+    `,
+      config: {
+        tsx: true,
+        aliases: {
+          components: "~/components",
+          utils: "~/lib/utils",
+        },
+      },
+    })
+  ).toMatchSnapshot()
+})
+
+test("transform dynamic imports with cn utility", async () => {
+  expect(
+    await transform({
+      filename: "test.ts",
+      raw: `async function loadCn() {
+  const { cn } = await import("@/lib/utils")
+  return cn
+}
+
+async function loadMultiple() {
+  const utils1 = await import("@/lib/utils")
+  const { cn, twMerge } = await import("@/lib/utils")
+  const other = await import("@/lib/other")
+}
+    `,
+      config: {
+        tsx: true,
+        aliases: {
+          components: "@/components",
+          utils: "@/lib/utils",
+        },
+      },
+    })
+  ).toMatchSnapshot()
+
+  expect(
+    await transform({
+      filename: "test.ts",
+      raw: `async function loadWorkspaceCn() {
+  const { cn } = await import("@/lib/utils")
+  return cn
+}
+    `,
+      config: {
+        tsx: true,
+        aliases: {
+          components: "@workspace/ui/components",
+          utils: "@workspace/ui/lib/utils",
+        },
+      },
+    })
+  ).toMatchSnapshot()
+})
+
+test("transform re-exports with dynamic imports", async () => {
+  expect(
+    await transform({
+      filename: "test.ts",
+      raw: `export { cn } from "@/lib/utils"
+export { Button } from "@/registry/new-york/ui/button"
+
+async function load() {
+  const module = await import("@/registry/new-york/ui/card")
+  return module
+}
+    `,
+      config: {
+        tsx: true,
+        aliases: {
+          components: "@/components",
+          utils: "@/lib/utils",
+        },
+      },
+    })
+  ).toMatchSnapshot()
+})

packages/shadcn/vitest.config.ts

@@ -9,6 +9,7 @@ export default defineConfig({
       "**/fixtures/**",
       "**/templates/**",
     ],
+    testTimeout: 8000,
   },
   plugins: [
     tsconfigPaths({