Extract watcher into its own package

.gitignore

@@ -5,6 +5,7 @@ coverage
 .nyc_output
 .cache
 dist
+lib
 .vscode/
 .idea/
 *.min.js

packages/core/parcel-bundler/package.json

@@ -68,6 +68,7 @@
     "tomlify-j0.4": "^3.0.0",
     "v8-compile-cache": "^2.0.0",
     "ws": "^5.1.1",
+    "@parcel/watcher": "1.10.3",
     "@parcel/workers": "^1.10.3",
     "@parcel/logger": "^1.10.3"
   },

packages/core/parcel-bundler/src/Bundler.js

@@ -4,7 +4,7 @@ const Parser = require('./Parser');
 const WorkerFarm = require('@parcel/workers');
 const Path = require('path');
 const Bundle = require('./Bundle');
-const Watcher = require('./Watcher');
+const Watcher = require('@parcel/watcher');
 const FSCache = require('./FSCache');
 const HMRServer = require('./HMRServer');
 const Server = require('./Server');

packages/core/watcher/.babelrc

@@ -0,0 +1,13 @@
+{
+  "presets": [
+    [
+      "@babel/preset-env",
+      {
+        "targets": {
+          "node": "6"
+        }
+      }
+    ]
+  ],
+  "plugins": ["@babel/plugin-transform-runtime"]
+}

packages/core/watcher/index.js

@@ -0,0 +1,5 @@
+// Node 8 supports native async functions - no need to use compiled code!
+module.exports =
+  parseInt(process.versions.node, 10) < 8
+    ? require('./lib/Watcher')
+    : require('./src/Watcher');

packages/core/watcher/package.json

@@ -0,0 +1,18 @@
+{
+  "name": "@parcel/watcher",
+  "version": "1.10.3",
+  "description": "Blazing fast, zero configuration web application bundler",
+  "main": "index.js",
+  "license": "MIT",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/parcel-bundler/parcel.git"
+  },
+  "scripts": {
+    "build": "babel src -d lib",
+    "prepublish": "yarn build"
+  },
+  "dependencies": {
+    "fswatcher-child": "^1.0.5"
+  }
+}