fix(cli): fix add registry item with at-property css rule (#8451)

* Add fixture and test

* Handle at-property as regular CSS rules in updateCssPlugin

* Add changeset entry

---------

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

.changeset/lazy-mails-wear.md

@@ -0,0 +1,5 @@
+---
+"shadcn": patch
+---
+
+fix adding registry item with CSS at-property

packages/shadcn/src/utils/updaters/update-css.ts

@@ -338,6 +338,10 @@ function updateCssPlugin(css: z.infer<typeof registryItemCssSchema>) {
                 }
               }
             }
+          }
+          // Handle at-property as regular CSS rules
+          else if (name === "property") {
+            processRule(root, selector, properties)
           } else {
             // Handle other at-rules normally
             processAtRule(root, name, params, properties)

packages/tests/fixtures/registry/example-at-property.json

@@ -0,0 +1,12 @@
+{
+  "$schema": "https://ui.shadcn.com/schema/registry-item.json",
+  "name": "example-at-property",
+  "type": "registry:style",
+  "css": {
+    "@property --foo": {
+      "syntax": "'<number>'",
+      "inherits": "false",
+      "initial-value": "0"
+    }
+  }
+}

packages/tests/src/tests/add.test.ts

@@ -296,4 +296,31 @@ describe("shadcn add", () => {
       await fs.readFile(path.join(fixturePath, "path/to/foo.txt"), "utf-8")
     ).toBe("Foo Bar")
   })
+
+  it("should add at-property", async () => {
+    const fixturePath = await createFixtureTestDirectory("next-app-init")
+    await npxShadcn(fixturePath, [
+      "add",
+      "../../fixtures/registry/example-at-property.json",
+      "--yes",
+    ])
+
+    const globalCssContent = await fs.readFile(
+      path.join(fixturePath, "app/globals.css"),
+      "utf-8"
+    )
+
+    expect(
+      cssHasProperties(globalCssContent, [
+        {
+          selector: "@property --foo",
+          properties: {
+            syntax: "'<number>'",
+            inherits: "false",
+            "initial-value": "0",
+          },
+        },
+      ])
+    ).toBe(true)
+  })
 })