install-deps: Match symlinked transitive deps correctly

1 files changed, 12 insertions, 3 deletions

diff --git a/lib/install/deps.js b/lib/install/deps.js
index 4137a5993..368e25030 100644
--- a/lib/install/deps.js
+++ b/lib/install/deps.js
@@ -183,7 +183,9 @@ function packageRelativePath (tree) {
   if (!tree) return ''
   var requested = tree.package._requested || {}
   var isLocal = requested.type === 'directory' || requested.type === 'file'
-  return isLocal ? requested.fetchSpec : tree.path
+  return isLocal ? requested.fetchSpec
+       : (tree.isLink || tree.isInLink) && !preserveSymlinks() ? tree.realpath
+       : tree.path
 }
 
 function matchingDep (tree, name) {
@@ -664,6 +666,13 @@ var findRequirement = exports.findRequirement = function (tree, name, requested,
   return findRequirement(tree.parent, name, requested, requestor)
 }
 
+function preserveSymlinks () {
+  if (!('NODE_PRESERVE_SYMLINKS' in process.env)) return false
+  const value = process.env.NODE_PRESERVE_SYMLINKS
+  if (value == null || value === '' || value === 'false' || value === 'no' || value === '0') return false
+  return true
+}
+
 // Find the highest level in the tree that we can install this module in.
 // If the module isn't installed above us yet, that'd be the very top.
 // If it is, then it's the level below where its installed.
@@ -695,7 +704,7 @@ var earliestInstallable = exports.earliestInstallable = function (requiredBy, tr
 
   var devDeps = tree.package.devDependencies || {}
   if (tree.isTop && devDeps[pkg.name]) {
-    var requested = npa.resolve(pkg.name, devDeps[pkg.name], tree.path)
+    var requested = childDependencySpecifier(tree, pkg.name, devDeps[pkg.name])
     if (!doesChildVersionMatch({package: pkg}, requested, tree)) {
       return null
     }
@@ -709,7 +718,7 @@ var earliestInstallable = exports.earliestInstallable = function (requiredBy, tr
   if (npm.config.get('global-style') && tree.parent.isTop) return tree
   if (npm.config.get('legacy-bundling')) return tree
 
-  if (!process.env.NODE_PRESERVE_SYMLINKS && /^[.][.][\\/]/.test(path.relative(tree.parent.realpath, tree.realpath))) return tree
+  if (!preserveSymlinks() && /^[.][.][\\/]/.test(path.relative(tree.parent.realpath, tree.realpath))) return tree
 
   return (earliestInstallable(requiredBy, tree.parent, pkg) || tree)
 }