Ignore buffer errors when the path is a directory

This would previously cause Atom to fail to launch if a buffer's
serialized path was now a directory on launch.

spec/project-spec.coffee

@@ -37,6 +37,19 @@ describe "Project", ->
         deserializedProject.getBuffers()[0].destroy()
         expect(deserializedProject.getBuffers().length).toBe 0
 
+
+    it "does not deserialize buffers when the path is a directory", ->
+      pathToOpen = path.join(temp.mkdirSync(), 'file.txt')
+
+      waitsForPromise ->
+        atom.project.open(pathToOpen)
+
+      runs ->
+        expect(atom.project.getBuffers().length).toBe 1
+        fs.mkdirSync(pathToOpen)
+        deserializedProject = atom.project.testSerialization()
+        expect(deserializedProject.getBuffers().length).toBe 0
+
   describe "when an editor is saved and the project has no path", ->
     it "sets the project's path to the saved file's parent directory", ->
       tempFile = temp.openSync().path

src/project.coffee

@@ -66,7 +66,12 @@ class Project extends Model
     buffers: _.compact(@buffers.map (buffer) -> buffer.serialize() if buffer.isRetained())
 
   deserializeParams: (params) ->
-    params.buffers = params.buffers.map (bufferState) -> atom.deserializers.deserialize(bufferState)
+    params.buffers = _.compact params.buffers.map (bufferState) ->
+      try
+        atom.deserializers.deserialize(bufferState)
+      catch error
+        # Ignore buffers for files that are now folders
+        throw error unless error.code is 'EISDIR'
     params