From 6f6a355d12d1522486f04b9bbf7795b349fc3234 Mon Sep 17 00:00:00 2001
From: jxdp <32483798+jxdp@users.noreply.github.com>
Date: Sat, 29 Jun 2024 11:01:19 +0100
Subject: [PATCH 1/2] [material-ui] Support CssVarsTheme in responsiveFontSizes
 types (#42760)

Signed-off-by: jxdp <32483798+jxdp@users.noreply.github.com>
---
 packages/mui-material/src/styles/responsiveFontSizes.d.ts | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/packages/mui-material/src/styles/responsiveFontSizes.d.ts b/packages/mui-material/src/styles/responsiveFontSizes.d.ts
index 394419e5a8ef0f..ce66cf94eb1347 100644
--- a/packages/mui-material/src/styles/responsiveFontSizes.d.ts
+++ b/packages/mui-material/src/styles/responsiveFontSizes.d.ts
@@ -1,6 +1,5 @@
 import { Breakpoint } from '@mui/system';
 import { Typography } from './createTypography';
-import { Theme } from './createTheme';
 
 export interface ResponsiveFontSizesOptions {
   breakpoints?: Breakpoint[];
@@ -9,7 +8,7 @@ export interface ResponsiveFontSizesOptions {
   variants?: Array<keyof Typography>;
 }
 
-export default function responsiveFontSizes(
-  theme: Theme,
+export default function responsiveFontSizes<T extends { typography: Typography }>(
+  theme: T,
   options?: ResponsiveFontSizesOptions,
-): Theme;
+): T;

From 6e9b84b4cdf61e52687efbe96fe6ef3585636d4d Mon Sep 17 00:00:00 2001
From: ZeeshanTamboli <zeeshan.tamboli@gmail.com>
Date: Sun, 30 Jun 2024 20:26:05 +0530
Subject: [PATCH 2/2] add TypeScript test

---
 .../src/styles/responsiveFontSize.spec.ts          | 14 ++++++++++++++
 1 file changed, 14 insertions(+)
 create mode 100644 packages/mui-material/src/styles/responsiveFontSize.spec.ts

diff --git a/packages/mui-material/src/styles/responsiveFontSize.spec.ts b/packages/mui-material/src/styles/responsiveFontSize.spec.ts
new file mode 100644
index 00000000000000..1eb6662ae2ef63
--- /dev/null
+++ b/packages/mui-material/src/styles/responsiveFontSize.spec.ts
@@ -0,0 +1,14 @@
+import {
+  responsiveFontSizes,
+  extendTheme,
+  createTheme,
+  Theme,
+  CssVarsTheme,
+} from '@mui/material/styles';
+import { expectType } from '@mui/types';
+
+const cssVarsTheme = responsiveFontSizes(extendTheme());
+expectType<Omit<Theme, 'applyStyles'> & CssVarsTheme, typeof cssVarsTheme>(cssVarsTheme);
+
+const theme = responsiveFontSizes(createTheme());
+expectType<Theme, typeof theme>(theme);