From 46272cd1927aac453a69397ffa6675c506ba3ac8 Mon Sep 17 00:00:00 2001
From: Max Brunsfeld <maxbrunsfeld@gmail.com>
Date: Wed, 18 Nov 2015 14:31:16 -0800
Subject: [PATCH] Load deserializers lazily

---
 .../{the-deserializer.js => deserializer-1.js}      |  2 +-
 .../package-with-deserializers/deserializer-2.js    |  6 ++++++
 .../package-with-deserializers/package.json         |  3 ++-
 spec/package-manager-spec.coffee                    | 13 +++++++++----
 src/package.coffee                                  | 10 ++++++++--
 5 files changed, 26 insertions(+), 8 deletions(-)
 rename spec/fixtures/packages/package-with-deserializers/{the-deserializer.js => deserializer-1.js} (62%)
 create mode 100644 spec/fixtures/packages/package-with-deserializers/deserializer-2.js

diff --git a/spec/fixtures/packages/package-with-deserializers/the-deserializer.js b/spec/fixtures/packages/package-with-deserializers/deserializer-1.js
similarity index 62%
rename from spec/fixtures/packages/package-with-deserializers/the-deserializer.js
rename to spec/fixtures/packages/package-with-deserializers/deserializer-1.js
index d70e62bfd..f4d7a1488 100644
--- a/spec/fixtures/packages/package-with-deserializers/the-deserializer.js
+++ b/spec/fixtures/packages/package-with-deserializers/deserializer-1.js
@@ -1,6 +1,6 @@
 module.exports = function (state) {
   return {
-    wasDeserializedBy: 'TheDeserializer',
+    wasDeserializedBy: 'Deserializer1',
     state: state
   }
 }
diff --git a/spec/fixtures/packages/package-with-deserializers/deserializer-2.js b/spec/fixtures/packages/package-with-deserializers/deserializer-2.js
new file mode 100644
index 000000000..3099d2b15
--- /dev/null
+++ b/spec/fixtures/packages/package-with-deserializers/deserializer-2.js
@@ -0,0 +1,6 @@
+module.exports = function (state) {
+  return {
+    wasDeserializedBy: 'Deserializer2',
+    state: state
+  }
+}
diff --git a/spec/fixtures/packages/package-with-deserializers/package.json b/spec/fixtures/packages/package-with-deserializers/package.json
index 867457e0a..377a5faf8 100644
--- a/spec/fixtures/packages/package-with-deserializers/package.json
+++ b/spec/fixtures/packages/package-with-deserializers/package.json
@@ -2,6 +2,7 @@
   "name": "package-with-deserializers",
   "version": "1.0.0",
   "atom-deserializers": {
-    "TheDeserializerName": "./the-deserializer.js"
+    "Deserializer1": "./deserializer-1.js",
+    "Deserializer2": "./deserializer-2.js"
   }
 }
diff --git a/spec/package-manager-spec.coffee b/spec/package-manager-spec.coffee
index 59e076834..843e9a932 100644
--- a/spec/package-manager-spec.coffee
+++ b/spec/package-manager-spec.coffee
@@ -82,11 +82,16 @@ describe "PackageManager", ->
     it "registers any deserializers specified in the package's package.json", ->
       atom.packages.loadPackage("package-with-deserializers")
 
-      state = {deserializer: 'TheDeserializerName', a: 'b'}
+      state1 = {deserializer: 'Deserializer1', a: 'b'}
+      expect(atom.deserializers.deserialize(state1)).toEqual {
+        wasDeserializedBy: 'Deserializer1'
+        state: state1
+      }
 
-      expect(atom.deserializers.deserialize(state)).toEqual {
-        wasDeserializedBy: 'TheDeserializer'
-        state: state
+      state2 = {deserializer: 'Deserializer2', c: 'd'}
+      expect(atom.deserializers.deserialize(state2)).toEqual {
+        wasDeserializedBy: 'Deserializer2'
+        state: state2
       }
 
   describe "::unloadPackage(name)", ->
diff --git a/src/package.coffee b/src/package.coffee
index b40cabac3..f933f93c3 100644
--- a/src/package.coffee
+++ b/src/package.coffee
@@ -256,8 +256,14 @@ class Package
 
   loadDeserializers: ->
     for name, implementationPath of @metadata['atom-deserializers']
-      deserialize = require(path.join(@path, implementationPath))
-      atom.deserializers.add({name, deserialize})
+      do =>
+        deserializePath = path.join(@path, implementationPath)
+        deserializeFunction = null
+        atom.deserializers.add
+          name: name,
+          deserialize: ->
+            deserializeFunction ?= require(deserializePath)
+            deserializeFunction.apply(this, arguments)
     return
 
   getStylesheetsPath: ->