Split module into @types/vscode and vscode-test

[octref]

Per the recent incidents (microsoft/vscode#69656), I think it's a good opportunity for us to split vscode node modules into 2 pieces:

• @types/vscode
• vscode-test

Explanation

vscode node module contains 3 scripts:

• compile: no longer used
• install: used to fetch vscode.d.ts according to engine.vscode in package.json
• test: used for extension test (also lib/testRunner)

Problems

• install asks update server for finding matching vscode.d.ts version (actual dts files fetched from GitHub). When update service is down, all extension deps install (CI or local development) could fail.
• yarn install and npm install can't be completed offline, even if they have caching: Add Switch for Offline Installation #93
• test depends on a lot of node modules (13MB). Everyone has to download them even if they just want to use the API.
• test needs some improvements. For example, for running extension tests against multiple workspaces, I had to pull out the test scripts and modify them manually Vetur. Also add flag / env var to enable downloading and unzipping to .vscode-test without running tests... #124, people want functionalities exposed from test so they can build upon them.

Benefits of splitting vscode into @types/vscode and vscode-test

• No awkward postinstall scripts after each npm install for extension
• Users don't have to pull in the 11MB dependencies of test. They pull a few kb of vscode.d.ts from @types/vscode, and it's fully cached by npm/yarn.
• vscode.d.ts are hosted on NPM which is pretty reliable. d.ts live in a @types package as they should be.
• test now lives in its own repo. It's easier to make improvements, release new versions, expose functionalities (for example, import { downloadVSCodeExecutable } from vscode-test).

Challenges

We can't put all versions of vscode.d.ts into @types/vscode and let TS infer which one, from engines.vscode.

However I think we can publish vscode.d.ts the same version as we do for VS Code, since all our 1.x API are backwards compatible. Most users also auto-update to latest version, so extension authors could use "@types/vscode": "^1.31.0" and safely get minor updates.

/cc @Microsoft/vscode for thoughts.

[alexdima]

👍 I like the proposal, I would suggest the small twist of shipping the .d.ts file directly within the vscode npm module instead of using @types/vscode. But that means we have to remember to always publish a new vscode npm module when we create a stable release. That should be fine, given we do it strictly after a VS Code release.

I would also vote for rewriting the script which downloads a vscode release to use https directly and the native installed tar instead of 13MB of gulp-* dependencies.

[octref]

rewriting the script which downloads a vscode release to use https directly

Agreed, something like this already works for macOS/Linux, which is what I'm using on Travis. vscode-test should also contain minimal or zero dependencies, so we'd be exempted from issues like event-stream.

let downloadPlatform

switch (process.platform) {
  case 'darwin':
    downloadPlatform = 'darwin'
    break
  case 'win32':
    downloadPlatform = 'win32-archive'
    break
  default:
    downloadPlatform = 'linux-x64'
}

const url = `https://update.code.visualstudio.com/latest/${downloadPlatform}/stable`

const https = require('https')
const fs = require('fs')
const cp = require('child_process')

https.get(url, res => {
  const zipUrl = res.headers.location

  if (zipUrl.endsWith('.zip')) {
    const outStream = fs.createWriteStream('vscode.zip')
    https.get(zipUrl, res => {
      res.pipe(outStream)
    })
    outStream.on('close', () => {
      if (process.platform === 'win32') {
        // need some windows powershell script or a zip library that supports windows
      } else {
        cp.execSync('unzip vscode.zip')
      }
    })
  } else {
    const outStream = fs.createWriteStream('vscode.tgz')
    https.get(zipUrl, res => {
      res.pipe(outStream)
    })
    outStream.on('close', () => {
      cp.execSync('tar -xzf vscode.tgz')
    })
  }
})

[bpasero]

@octref wanna do some PRs on this? E.g. the download part?

[octref]

@bpasero Sure.