Configure Gitpod online dev environment

.gitpod.Dockerfile

@@ -0,0 +1,6 @@
+FROM gitpod/workspace-full
+
+RUN sudo apt-get update \
+  && sudo apt-get install -y \
+    g++ gcc make python2.7 pkg-config libx11-dev libxkbfile-dev libsecret-1-dev python-is-python3 rsync \
+  && sudo rm -rf /var/lib/apt/lists/*

.gitpod.yml

@@ -0,0 +1,38 @@
+image:
+  file: .gitpod.Dockerfile
+tasks:
+  - init: |
+      yarn
+      yarn build
+      mkdir -p lib/vscode/out
+      sed -i 's/The Web Worker Extension Host did not start in 10s/The Web Worker Extension Host did not start in 60s/g' ./lib/vscode/src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts
+      sed -i 's/}, 10000);/}, 60000);/g' ./lib/vscode/src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts
+    command: |
+      echo "======================="
+      echo "Please run 'yarn watch'"
+      echo "======================="
+  - command: |
+      echo "==========================================================================="
+      echo "Please wait for 'yarn watch' to complete compilation, then run 'yarn serve'"
+      echo "==========================================================================="
+ports:
+  - port: 5000
+    onOpen: open-browser
+github:
+  prebuilds:
+    # enable for the master/default branch (defaults to true)
+    master: true
+    # enable for all branches in this repo (defaults to false)
+    branches: true
+    # enable for pull requests coming from this repo (defaults to true)
+    pullRequests: true
+    # enable for pull requests coming from forks (defaults to false)
+    pullRequestsFromForks: true
+    # add a check to pull requests (defaults to true)
+    addCheck: true
+    # add a "Review in Gitpod" button as a comment to pull requests (defaults to false)
+    addComment: true
+    # add a "Review in Gitpod" button to the pull request's description (defaults to false)
+    addBadge: false
+    # add a label once the prebuild is ready to pull requests (defaults to false)
+    addLabel: false

README.md

@@ -35,6 +35,14 @@ javascript: window.location.href = window.location.href.replace(/github(1s)?.com
 
 ## Development
 
+### Cloud-based development
+
+You can start an online development environment with [Gitpod](https://www.gitpod.io) by clicking the following button:
+
+[![Gitpod ready-to-code](https://img.shields.io/badge/Gitpod-ready--to--code-blue?logo=gitpod)](https://gitpod.io/#https://github.com/conwnet/github1s)
+
+### Local development
+
 You need [these prerequisites (the same ones as for VS Code)](https://github.com/microsoft/vscode/wiki/How-to-Contribute#prerequisites) for development.
 
 ```bash

extensions/svelte-web/package.json

@@ -3,7 +3,7 @@
   "version": "0.5.0",
   "description": "Svelte language support for VS Code",
   "scripts": {
-    "build:grammar": "npx js-yaml syntaxes/svelte.tmLanguage.src.yaml > syntaxes/svelte.tmLanguage.json",
+    "build:grammar": "js-yaml syntaxes/svelte.tmLanguage.src.yaml > syntaxes/svelte.tmLanguage.json",
     "build": "npm run build:ts && npm run build:grammar",
     "vscode:prepublish": "npm run build && npm prune --production",
     "compile": "npm run build:grammar",
@@ -119,5 +119,8 @@
         }
       }
     ]
+  },
+  "devDependencies": {
+    "js-yaml": "^4.0.0"
   }
 }