Typescript pulling all MUI files - super slow compilation

• This is a v1.x issue (v0.x is no longer maintained).
• I have searched the issues of this repository and believe that this is not a duplicate.

Expected Behavior

TSC should compile in about 3-8 seconds.

Current Behavior

TSC takes over 1 minute to compile, because it’s pulling the entire library, with over half a million types. running tsc --extendedDiagnostics --listFiles --noEmit

and it goes on…

If I remove the MUI folder (resulting in lots of errors of course)

Context

I’m only using 10 components in the entire app, all imported like this: import CircularProgress from '@material-ui/core/CircularProgress/CircularProgress';

It should only import the relevant files and types.

My tsconfig:

{
  "compilerOptions": {
    "baseUrl": "./src",
    "outDir": "build/dist",
    "target": "es5",
    "lib": ["es6", "es7", "dom"],
    "sourceMap": true,
    "allowJs": false,
    "jsx": "react",
    "esModuleInterop": true,
    "skipLibCheck": true,
    "moduleResolution": "node",
    "allowSyntheticDefaultImports": true,
    "rootDir": "./src",
    "noEmitOnError": false,
    "isolatedModules": true,
    "strictPropertyInitialization": false,
    "forceConsistentCasingInFileNames": true,
    "noFallthroughCasesInSwitch": true,
    "noErrorTruncation": true,
    "noImplicitReturns": true,
    "noImplicitAny": true,
    "noImplicitThis": true,
    "strictNullChecks": true,
    "diagnostics": true,
    "suppressImplicitAnyIndexErrors": true,
    "noUnusedLocals": true
  },
  "include": [
    "src/**/*"
  ],
  "exclude": [
    "dist",
    "build",
    "node_modules",
    "src/**/__tests__"
  ],
  "defaultSeverity": "warning"
}

My @types folder:

Any ideas why this happens?

Thank you for your help!!!

Your Environment

Tech	Version
Material-UI	v1.2.2
React	latest
browser
etc

[jtreminio]

@manpreetnarang instead of

import {
  AppBar,
  Button,
  Hidden,
  IconButton,
  Toolbar,
} from '@material-ui/core';
import { Menu } from '@material-ui/icons';

Do this:

import AppBar from '@material-ui/core/AppBar';
import Button from '@material-ui/core/Button';
import Hidden from '@material-ui/core/Hidden';
import IconButton from '@material-ui/core/IconButton';
import Toolbar from '@material-ui/core/Toolbar';

import Menu from '@material-ui/icons/Menu';

[weswigham]

This is an issue with Typescript, not with MUI. There is nothing MUI can do about this

@Pajn Actually while we definitely do (did? we should be publishing a fix on nightlies tonight) have a perf problem, there’s an issue in MUI that is causing us to do more work than we should need to for a given deep import, too (which is why the file count goes up so much with a single component import)! Specifically, you have imports like this one:

import { StandardProps } from '..';

That import references the root index.d.ts - your root index.d.ts imports all components (to reexport them), causing us to load every type definition in MUI (we won’t typecheck them unless requested, but we will load them all from disk and parse them, which has a cost). If you moved your utilitity types like StandardProps into a separate file from the root index.d.ts and did a direct import of them, it would cut down on the fileset loaded for a given component fairly significantly.