feat: add env variable to skip binary download on npm install (electron#17627)

Joshua Westerheide · John Kleinschmidt · commit a59dc56fa6dd · 2019-05-03T10:17:15.000-07:00
* feat: add env variable to skip binary download on npm install

* docs: add "Skip binary download" section to install tutorial
diff --git a/docs/tutorial/installation.md b/docs/tutorial/installation.md
@@ -97,6 +97,17 @@ a text file. A typical cache might look like this:
 ├── SHASUMS256.txt-1.8.2-beta.3
 ```
 
+## Skip binary download
+When installing the `electron` NPM package, it automatically downloads the electron binary.
+
+This can sometimes be unnecessary, e.g. in a CI environment, when testing another component.
+
+To prevent the binary from being downloaded when you install all npm dependencies you can set the environment variable `ELECTRON_SKIP_BINARY_DOWNLOAD`.
+E.g.:
+```sh
+ELECTRON_SKIP_BINARY_DOWNLOAD=1 npm install
+```
+
 ## Troubleshooting
 
 When running `npm install electron`, some users occasionally encounter
diff --git a/npm/install.js b/npm/install.js
@@ -15,6 +15,10 @@ try {
   // do nothing
 }
 
+if (process.env.ELECTRON_SKIP_BINARY_DOWNLOAD) {
+  process.exit(0)
+}
+
 var platformPath = getPlatformPath()
 
 var electronPath = process.env.ELECTRON_OVERRIDE_DIST_PATH || path.join(__dirname, 'dist', platformPath)

Original file line number	Diff line number	Diff line change
`@@ -15,6 +15,10 @@ try {`
`15`	`15`	`// do nothing`
`16`	`16`	`}`
`17`	`17`
	`18`	`+if (process.env.ELECTRON_SKIP_BINARY_DOWNLOAD) {`
	`19`	`+ process.exit(0)`
	`20`	`+}`
	`21`	`+`
`18`	`22`	`var platformPath = getPlatformPath()`
`19`	`23`
`20`	`24`	`var electronPath = process.env.ELECTRON_OVERRIDE_DIST_PATH \|\| path.join(__dirname, 'dist', platformPath)`