[core] Update classes generation logic

packages/material-ui-unstyled/src/BadgeUnstyled/BadgeUnstyled.js

@@ -3,33 +3,25 @@ import PropTypes from 'prop-types';
 import clsx from 'clsx';
 import { unstable_capitalize as capitalize, usePreviousProps } from '@material-ui/utils';
 import isHostComponent from '../utils/isHostComponent';
-import badgeUnstyledClasses, { getBadgeUtilityClass } from './badgeUnstyledClasses';
+import composeClasses from '../composeClasses';
+import { getBadgeUtilityClass } from './badgeUnstyledClasses';
 
 const useUtilityClasses = (styleProps) => {
-  const { variant, anchorOrigin, overlap, invisible, classes = {} } = styleProps;
-
-  return {
-    root: clsx(badgeUnstyledClasses.root, classes.root),
-    badge: clsx(
-      badgeUnstyledClasses.badge,
-      classes.badge,
-      getBadgeUtilityClass(variant),
-      badgeUnstyledClasses[
-        `anchorOrigin${capitalize(anchorOrigin.vertical)}${capitalize(
-          anchorOrigin.horizontal,
-        )}${capitalize(overlap)}`
-      ],
-      classes[
-        `anchorOrigin${capitalize(anchorOrigin.vertical)}${capitalize(
-          anchorOrigin.horizontal,
-        )}${capitalize(overlap)}`
-      ],
-      {
-        [badgeUnstyledClasses.invisible]: invisible,
-        [classes.invisible]: invisible,
-      },
-    ),
+  const { variant, anchorOrigin, overlap, invisible, classes } = styleProps;
+
+  const slots = {
+    root: ['root'],
+    badge: [
+      'badge',
+      variant, // there was only utility class for the variant previously
+      `anchorOrigin${capitalize(anchorOrigin.vertical)}${capitalize(
+        anchorOrigin.horizontal,
+      )}${capitalize(overlap)}`,
+      invisible && 'invisible',
+    ],
   };
+
+  return composeClasses({ slots, classes, getUtilityClass: getBadgeUtilityClass });
 };
 
 const BadgeUnstyled = React.forwardRef(function BadgeUnstyled(props, ref) {

packages/material-ui-unstyled/src/SliderUnstyled/SliderUnstyled.js

@@ -12,7 +12,8 @@ import {
   visuallyHidden,
 } from '@material-ui/utils';
 import isHostComponent from '../utils/isHostComponent';
-import sliderUnstyledClasses from './sliderUnstyledClasses';
+import composeClasses from '../composeClasses';
+import { getSliderUtilityClass } from './sliderUnstyledClasses';
 import SliderValueLabelUnstyled from './SliderValueLabelUnstyled';
 
 function asc(a, b) {
@@ -150,36 +151,31 @@ function doesSupportTouchActionNone() {
 }
 
 const useUtilityClasses = (styleProps) => {
-  const { disabled, marked, orientation, track, classes = {} } = styleProps;
-
-  return {
-    root: clsx(sliderUnstyledClasses.root, classes.root, {
-      [sliderUnstyledClasses.disabled]: disabled,
-      [classes.disabled]: disabled,
-      [sliderUnstyledClasses.marked]: marked,
-      [classes.marked]: marked,
-      [sliderUnstyledClasses.vertical]: orientation === 'vertical',
-      [classes.vertical]: orientation === 'vertical',
-      [sliderUnstyledClasses.trackInverted]: track === 'inverted',
-      [classes.trackInverted]: track === 'inverted',
-      [sliderUnstyledClasses.trackFalse]: track === false,
-      [classes.trackFalse]: track === false,
-    }),
-    rail: clsx(sliderUnstyledClasses.rail, classes.rail),
-    track: clsx(sliderUnstyledClasses.track, classes.track),
-    mark: clsx(sliderUnstyledClasses.mark, classes.mark),
-    markActive: clsx(sliderUnstyledClasses.markActive, classes.markActive),
-    markLabel: clsx(sliderUnstyledClasses.markLabel, classes.markLabel),
-    markLabelActive: clsx(sliderUnstyledClasses.markLabelActive, classes.markLabelActive),
-    valueLabel: clsx(sliderUnstyledClasses.valueLabel, classes.valueLabel),
-    thumb: clsx(sliderUnstyledClasses.thumb, classes.thumb, {
-      [classes.disabled]: disabled,
-      [sliderUnstyledClasses.disabled]: disabled,
-    }),
-    active: clsx(sliderUnstyledClasses.active, classes.active),
-    disabled: clsx(sliderUnstyledClasses.disabled, classes.disabled),
-    focusVisible: clsx(sliderUnstyledClasses.focusVisible, classes.focusVisible),
+  const { disabled, marked, orientation, track, classes } = styleProps;
+
+  const slots = {
+    root: [
+      'root',
+      disabled && 'disabled',
+      marked && 'marked',
+      orientation === 'vertical' && 'vertical',
+      track === 'inverted' && 'trackInverted',
+      track === false && 'trackFalse',
+    ],
+    rail: ['rail'],
+    track: ['track'],
+    mark: ['mark'],
+    markActive: ['markActive'],
+    markLabel: ['markLabel'],
+    markLabelActive: ['markLabelActive'],
+    valueLabel: ['valueLabel'],
+    thumb: ['thumb', disabled && 'disabled'],
+    active: ['active'],
+    disabled: ['disabled'],
+    focusVisible: ['focusVisible'],
   };
+
+  return composeClasses({ slots, classes, getUtilityClass: getSliderUtilityClass });
 };
 
 const Forward = ({ children }) => children;

packages/material-ui-unstyled/src/composeClasses/composeClasses.d.ts

@@ -0,0 +1,5 @@
+export default function composeClasses(options: {
+  slots: Record<string, string[]>;
+  classes: Record<string, string>;
+  getUtilityClass: (slot: string) => string;
+}): Record<string, string>;

packages/material-ui-unstyled/src/composeClasses/composeClasses.js

@@ -0,0 +1,19 @@
+function composeClasses({ slots = {}, classes = {}, getUtilityClass = () => '' }) {
+  const output = {};
+
+  Object.keys(slots).forEach((slot) => {
+    output[slot] = slots[slot]
+      .reduce((acc, key) => {
+        if (classes && classes[key]) {
+          acc.push(classes[key]);
+        }
+        acc.push(getUtilityClass(key));
+        return acc;
+      }, [])
+      .join(' ');
+  });
+
+  return output;
+}
+
+export default composeClasses;

packages/material-ui-unstyled/src/composeClasses/composeClasses.test.js

@@ -0,0 +1,38 @@
+import { expect } from 'chai';
+import composeClasses from './composeClasses';
+
+describe('composeClasses', () => {
+  it('should generate the classes based on the slots', () => {
+    expect(
+      composeClasses({
+        slots: {
+          root: ['root', 'standard'],
+          slot: ['slot'],
+        },
+        getUtilityClass: (slot) => `MuiTest-${slot}`,
+      }),
+    ).to.deep.equal({
+      root: 'MuiTest-root MuiTest-standard',
+      slot: 'MuiTest-slot',
+    });
+  });
+
+  it('should consider classes if available', () => {
+    expect(
+      composeClasses({
+        slots: {
+          root: ['root', 'standard'],
+          slot: ['slot'],
+        },
+        getUtilityClass: (slot) => `MuiTest-${slot}`,
+        classes: {
+          standard: 'standardOverride',
+          slot: 'slotOverride',
+        },
+      }),
+    ).to.deep.equal({
+      root: 'MuiTest-root standardOverride MuiTest-standard',
+      slot: 'slotOverride MuiTest-slot',
+    });
+  });
+});

packages/material-ui-unstyled/src/composeClasses/index.d.ts

@@ -0,0 +1,2 @@
+export { default } from './composeClasses';
+export * from './composeClasses';

packages/material-ui-unstyled/src/composeClasses/index.js

@@ -0,0 +1 @@
+export { default } from './composeClasses';

packages/material-ui-unstyled/src/index.d.ts

@@ -10,4 +10,7 @@ export * from './generateUtilityClass';
 export { default as generateUtilityClasses } from './generateUtilityClasses';
 export * from './generateUtilityClasses';
 
+export { default as unstable_composeClasses } from './composeClasses';
+export * from './composeClasses';
+
 export * from './utils';

packages/material-ui-unstyled/src/index.js

@@ -8,4 +8,6 @@ export { default as generateUtilityClass } from './generateUtilityClass';
 
 export { default as generateUtilityClasses } from './generateUtilityClasses';
 
+export { default as unstable_composeClasses } from './composeClasses';
+
 export * from './utils';

packages/material-ui/src/Avatar/Avatar.js

@@ -2,6 +2,7 @@ import * as React from 'react';
 import PropTypes from 'prop-types';
 import clsx from 'clsx';
 import { deepmerge } from '@material-ui/utils';
+import { unstable_composeClasses as composeClasses } from '@material-ui/unstyled';
 import experimentalStyled from '../styles/experimentalStyled';
 import useThemeProps from '../styles/useThemeProps';
 import Person from '../internal/svg-icons/Person';
@@ -19,16 +20,15 @@ const overridesResolver = (props, styles) => {
 };
 
 const useUtilityClasses = (styleProps) => {
-  const { classes = {}, variant, colorDefault } = styleProps;
+  const { classes, variant, colorDefault } = styleProps;
 
-  return {
-    root: clsx(avatarClasses.root, classes.root, getAvatarUtilityClass(variant), classes[variant], {
-      [avatarClasses.colorDefault]: colorDefault,
-      [classes.colorDefault]: colorDefault,
-    }),
-    img: clsx(avatarClasses.img, classes.img),
-    fallback: clsx(avatarClasses.fallback, classes.fallback),
+  const slots = {
+    root: ['root', variant, colorDefault && 'colorDefault'],
+    img: ['img'],
+    fallback: ['fallback'],
   };
+
+  return composeClasses({ slots, classes, getUtilityClass: getAvatarUtilityClass });
 };
 
 const AvatarRoot = experimentalStyled(

packages/material-ui/src/Button/Button.js

@@ -2,6 +2,7 @@ import * as React from 'react';
 import PropTypes from 'prop-types';
 import clsx from 'clsx';
 import { deepmerge } from '@material-ui/utils';
+import { unstable_composeClasses as composeClasses } from '@material-ui/unstyled';
 import experimentalStyled from '../styles/experimentalStyled';
 import useThemeProps from '../styles/useThemeProps';
 import { alpha } from '../styles/colorManipulator';
@@ -35,41 +36,23 @@ const overridesResolver = (props, styles) => {
 const useUtilityClasses = (styleProps) => {
   const { color, disableElevation, fullWidth, size, variant, classes = {} } = styleProps;
 
-  return {
-    root: clsx(
-      buttonClasses.root,
-      classes.root,
-      getButtonUtilityClass(variant),
-      classes[variant],
-      getButtonUtilityClass(`${variant}${capitalize(color)}`),
-      classes[[`${variant}${capitalize(color)}`]],
-      getButtonUtilityClass(`size${capitalize(size)}`),
-      classes[`size${capitalize(size)}`],
-      getButtonUtilityClass(`${variant}Size${capitalize(size)}`),
-      classes[`${variant}Size${capitalize(size)}`],
-      {
-        [buttonClasses.colorInherit]: color === 'inherit',
-        [classes.colorInherit]: color === 'inherit',
-        [buttonClasses.disableElevation]: disableElevation,
-        [classes.disableElevation]: disableElevation,
-        [buttonClasses.fullWidth]: fullWidth,
-        [classes.fullWidth]: fullWidth,
-      },
-    ),
-    label: clsx(buttonClasses.label, classes.label),
-    startIcon: clsx(
-      buttonClasses.startIcon,
-      classes.startIcon,
-      getButtonUtilityClass(`iconSize${capitalize(size)}`),
-      classes[`iconSize${capitalize(size)}`],
-    ),
-    endIcon: clsx(
-      buttonClasses.endIcon,
-      classes.endIcon,
-      getButtonUtilityClass(`iconSize${capitalize(size)}`),
-      classes[`iconSize${capitalize(size)}`],
-    ),
+  const slots = {
+    root: [
+      'root',
+      variant,
+      `${variant}${capitalize(color)}`,
+      `size${capitalize(size)}`,
+      `${variant}Size${capitalize(size)}`,
+      color === 'inherit' && 'colorInherit',
+      disableElevation && 'disableElevation',
+      fullWidth && 'fullWidth',
+    ],
+    label: ['label'],
+    startIcon: ['startIcon', `iconSize${capitalize(size)}`],
+    endIcon: ['endIcon', `iconSize${capitalize(size)}`],
   };
+
+  return composeClasses({ slots, classes, getUtilityClass: getButtonUtilityClass });
 };
 
 const commonIconStyles = (styleProps) => ({

packages/material-ui/src/ButtonBase/ButtonBase.js

@@ -2,13 +2,14 @@ import * as React from 'react';
 import PropTypes from 'prop-types';
 import clsx from 'clsx';
 import { deepmerge, elementTypeAcceptingRef, refType } from '@material-ui/utils';
+import { unstable_composeClasses as composeClasses } from '@material-ui/unstyled';
 import experimentalStyled from '../styles/experimentalStyled';
 import useThemeProps from '../styles/useThemeProps';
 import useForkRef from '../utils/useForkRef';
 import useEventCallback from '../utils/useEventCallback';
 import useIsFocusVisible from '../utils/useIsFocusVisible';
 import TouchRipple from './TouchRipple';
-import buttonBaseClasses from './buttonBaseClasses';
+import { getButtonBaseUtilityClass } from './buttonBaseClasses';
 
 const overridesResolver = (props, styles) => {
   const { styleProps } = props;
@@ -22,15 +23,21 @@ const overridesResolver = (props, styles) => {
 const useUtilityClasses = (styleProps) => {
   const { disabled, focusVisible, focusVisibleClassName, classes = {} } = styleProps;
 
-  return {
-    root: clsx(buttonBaseClasses.root, classes.root, {
-      [buttonBaseClasses.disabled]: disabled,
-      [classes.disabled]: disabled,
-      [buttonBaseClasses.focusVisible]: focusVisible,
-      [classes.focusVisible]: focusVisible,
-      [focusVisibleClassName]: focusVisible,
-    }),
+  const slots = {
+    root: ['root', disabled && 'disabled', focusVisible && 'focusVisible'],
   };
+
+  const composedClasses = composeClasses({
+    slots,
+    classes,
+    getUtilityClass: getButtonBaseUtilityClass,
+  });
+
+  if (focusVisible && focusVisibleClassName) {
+    composedClasses.root += ` ${focusVisibleClassName}`;
+  }
+
+  return composedClasses;
 };
 
 export const ButtonBaseRoot = experimentalStyled(

packages/material-ui/src/Container/Container.js

@@ -2,9 +2,10 @@ import * as React from 'react';
 import PropTypes from 'prop-types';
 import clsx from 'clsx';
 import { deepmerge } from '@material-ui/utils';
+import { unstable_composeClasses as composeClasses } from '@material-ui/unstyled';
 import useThemeProps from '../styles/useThemeProps';
 import experimentalStyled from '../styles/experimentalStyled';
-import containerClasses, { getContainerUtilityClass } from './containerClasses';
+import { getContainerUtilityClass } from './containerClasses';
 import capitalize from '../utils/capitalize';
 
 const overridesResolver = (props, styles) => {
@@ -18,22 +19,18 @@ const overridesResolver = (props, styles) => {
 };
 
 const useUtilityClasses = (styleProps) => {
-  const { classes = {}, fixed, disableGutters, maxWidth } = styleProps;
+  const { classes, fixed, disableGutters, maxWidth } = styleProps;
 
-  return {
-    root: clsx(
-      containerClasses.root,
-      classes.root,
-      getContainerUtilityClass(`maxWidth${capitalize(String(maxWidth))}`),
-      classes[`maxWidth${capitalize(String(maxWidth))}`],
-      {
-        [containerClasses.fixed]: fixed,
-        [classes.fixed]: fixed,
-        [containerClasses.disableGutters]: disableGutters,
-        [classes.disableGutters]: disableGutters,
-      },
-    ),
+  const slots = {
+    root: [
+      'root',
+      maxWidth && `maxWidth${capitalize(String(maxWidth))}`,
+      fixed && 'fixed',
+      disableGutters && 'disableGutters',
+    ],
   };
+
+  return composeClasses({ slots, classes, getUtilityClass: getContainerUtilityClass });
 };
 
 const ContainerRoot = experimentalStyled(