From 6d6708bcf8ad426f66c74a763ccba646ce21a7d7 Mon Sep 17 00:00:00 2001
From: Lauri Luotola <lauri.luotola@gmail.com>
Date: Wed, 28 Oct 2026 12:27:46 +0200
Subject: [PATCH] fix(react): resolve plain props before the polymorphic as
 overload

Spreading the result of a generic function call into a styled component
fails with TS2698 since #1479 added the generic `as` overload. TypeScript
does not infer such a spread against that overload, so add a non-generic
overload without `as` first. The `as` overloads are unchanged.
---
 .changeset/polymorphic-as-generic-spread.md | 5 +++++
 packages/react/__dtslint__/styled-jsx.tsx   | 9 +++++++++
 packages/react/src/styled.ts                | 5 +++++
 3 files changed, 19 insertions(+)
 create mode 100644 .changeset/polymorphic-as-generic-spread.md

diff --git a/.changeset/polymorphic-as-generic-spread.md b/.changeset/polymorphic-as-generic-spread.md
new file mode 100644
index 000000000..820ee0beb
--- /dev/null
+++ b/.changeset/polymorphic-as-generic-spread.md
@@ -0,0 +1,5 @@
+---
+'@linaria/react': patch
+---
+
+Fix TypeScript inference for generic spread props on styled components (TS2698).
diff --git a/packages/react/__dtslint__/styled-jsx.tsx b/packages/react/__dtslint__/styled-jsx.tsx
index d4b73f7e6..9e61adbe1 100644
--- a/packages/react/__dtslint__/styled-jsx.tsx
+++ b/packages/react/__dtslint__/styled-jsx.tsx
@@ -9,3 +9,12 @@ const Button = styled.button``;
 <Button href="/" />;
 // @ts-expect-error href is not a button property
 <Button as="button" href="/" />;
+
+declare function getProps<
+  T extends React.InputHTMLAttributes<HTMLInputElement>,
+>(props?: T): T;
+
+const Input = styled.input``;
+
+// A spread of a generic call must not depend on the `as` overload.
+<Input {...getProps()} disabled />;
diff --git a/packages/react/src/styled.ts b/packages/react/src/styled.ts
index 28cb6adad..cfe200120 100644
--- a/packages/react/src/styled.ts
+++ b/packages/react/src/styled.ts
@@ -273,6 +273,11 @@ type IntrinsicElementProps<TName extends keyof IntrinsicElements> =
   keyof IntrinsicElements extends TName ? unknown : IntrinsicElements[TName];
 
 type StyledComponentWithAs<TProps> = {
+  // Tried first so that inference in JSX does not have to go through the generic `as` overload.
+  (
+    props: TProps & { as?: undefined },
+    context?: any
+  ): ReturnType<React.FunctionComponent<TProps>>;
   <TAs extends keyof IntrinsicElements>(
     props: TProps & { as: TAs } & NoInfer<IntrinsicElementProps<TAs>>,
     context?: any