fix: preserve legacy button compatibility classes

Author: root

packages/web/src/components/ui/button/index.test.tsx

@@ -42,6 +42,21 @@ describe("Button", () => {
     expect(screen.getByRole("button", { name: "Large" })).toBeInTheDocument();
   });
 
+  it("preserves legacy compatibility classes for migrated callers", () => {
+    render(
+      <Button variant="primary" size="lg" className="auth-submit">
+        Submit
+      </Button>
+    );
+
+    expect(screen.getByRole("button", { name: "Submit" })).toHaveClass(
+      "btn",
+      "btn-primary",
+      "btn-lg",
+      "auth-submit"
+    );
+  });
+
   it("disables click handlers while loading", async () => {
     const user = userEvent.setup();
     const onClick = vi.fn();

packages/web/src/components/ui/button/index.tsx

@@ -40,6 +40,19 @@ const sizeClassMap: Record<ButtonSize, string | undefined> = {
   lg: styles.lg,
 };
 
+const legacyVariantClassMap: Record<ButtonVariant, string> = {
+  primary: "btn-primary",
+  secondary: "btn-secondary",
+  ghost: "btn-ghost",
+  danger: "btn-danger",
+};
+
+const legacySizeClassMap: Record<ButtonSize, string | undefined> = {
+  sm: "btn-sm",
+  md: undefined,
+  lg: "btn-lg",
+};
+
 const ButtonContent = ({
   children,
   leadingIcon,
@@ -82,6 +95,9 @@ export const Button = (props: ButtonProps) => {
     styles.btn,
     variantClassMap[variant],
     sizeClassMap[size],
+    "btn",
+    legacyVariantClassMap[variant],
+    legacySizeClassMap[size],
     loading ? styles.loading : undefined,
     className
   );