@mui/styles/modern/getThemeProps/getThemeProps.js

MUI Styles - The legacy JSS-based styling solution of Material UI.

export default function getThemeProps(params) {
  const {
    theme,
    name,
    props
  } = params;
  if (!theme || !theme.components || !theme.components[name] || !theme.components[name].defaultProps) {
    return props;
  }
  const output = {
    ...props
  };

  // Resolve default props, code borrow from React source.
  // https://github.com/facebook/react/blob/15a8f031838a553e41c0b66eb1bcf1da8448104d/packages/react/src/ReactElement.js#L221
  const defaultProps = theme.components[name].defaultProps;
  let propName;
  for (propName in defaultProps) {
    if (output[propName] === undefined) {
      output[propName] = defaultProps[propName];
    }
  }
  return output;
}