save: Use rawSpec when saving git-type specifiers

Since npm-package-arg strips a preceding `git+` from urls, and the stripped
urls will cause trouble when loading the package the next time, we have to
make sure that in this case at least we save the rawSpec not the spec.

PR-URL: npm#11091
Fixes: npm#9679
Credit: @gagern
Reviewed-By: @othiym23
Reviewed-By: @iarna

lib/install/save.js

@@ -180,8 +180,10 @@ function computeVersionSpec (child) {
         pathname: relativePath
       })
     }
-  } else {
+  } else if (requested.type === 'hosted') {
     return requested.spec
+  } else {
+    return requested.rawSpec
   }
 }
 

test/tap/add-remote-git-file.js

@@ -45,6 +45,29 @@ test('cache from repo', function (t) {
   })
 })
 
+test('save install', function (t) {
+  process.chdir(pkg)
+  fs.writeFileSync('package.json', JSON.stringify({
+    name: 'parent',
+    version: '5.4.3'
+  }, null, 2) + '\n')
+  var prev = npm.config.get('save')
+  npm.config.set('save', true)
+  npm.commands.install('.', [cloneURL], function (er) {
+    npm.config.set('save', prev)
+    t.ifError(er, 'npm installed via git')
+    var pj = JSON.parse(fs.readFileSync('package.json', 'utf-8'))
+    var dep = pj.dependencies.child
+    t.equal(
+      url.parse(dep).protocol,
+      'git+file:',
+      'npm didn\'t strip the git+ from git+file://'
+    )
+
+    t.end()
+  })
+})
+
 test('clean', function (t) {
   cleanup()
   t.end()