Do not modify existing .idea/vcs.xml. Closes #31.

sbt-idea-core/src/main/scala/IdeaProjectDescriptor.scala

@@ -74,15 +74,17 @@ class IdeaProjectDescriptor(val project: BasicDependencyProject, val log: Logger
 
     if (projectPath.exists) {
       val configDir = new File(projectPath, ".idea")
+      def configFile(name: String) = new File(configDir, name)
       configDir.mkdirs
 
       Seq(
         "modules.xml" -> project(projectModuleManagerComponent),
-        "misc.xml" -> miscTransformer.transform(miscXml(configDir)).firstOption.get,
-        "vcs.xml" -> project(vcsComponent)
+        "misc.xml" -> miscTransformer.transform(miscXml(configDir)).firstOption.get
       ) foreach { case (fileName, xmlNode) => saveFile(configDir, fileName, xmlNode) }
 
-      val librariesDir = new File(configDir, "libraries")
+      if (!configFile("vcs.xml").exists) saveFile(configDir, "vcs.xml", project(vcsComponent))
+
+      val librariesDir = configFile("libraries")
       librariesDir.mkdirs
       saveFile(librariesDir, "buildScala.xml", libraryTableComponent("buildScala", buildScalaJarDir, true))
       saveFile(librariesDir, "defScala.xml", libraryTableComponent("defScala", defScalaJarDir, false))

sbt-idea-tests/src/sbt-test/idea-plugin/preserve-existing-vcs-xml/project/build.properties

@@ -0,0 +1,6 @@
+project.organization=foo
+project.name=scripted-test
+sbt.version=0.7.4
+project.version=1.0
+build.scala.versions=2.7.7
+project.initialize=false

sbt-idea-tests/src/sbt-test/idea-plugin/preserve-existing-vcs-xml/project/build/ScriptedTestProject.scala

@@ -0,0 +1,3 @@
+import sbt._
+
+class ScriptedTestProject(info: ProjectInfo) extends DefaultProject(info) with ScriptedTestAssertTasks with IdeaProject

sbt-idea-tests/src/sbt-test/idea-plugin/preserve-existing-vcs-xml/project/plugins/Plugins.scala

@@ -0,0 +1,9 @@
+import sbt._
+
+class Plugins(info: ProjectInfo) extends PluginDefinition(info) {
+  val testedVersion = "0.2-SNAPSHOT"
+  val groupId = "com.github.mpeltonen"
+  val ideaPlugin = groupId % "sbt-idea-plugin" % testedVersion
+  val scriptedTestUtils = groupId % "sbt-idea-tests_2.7.7" % testedVersion
+}
+

sbt-idea-tests/src/sbt-test/idea-plugin/preserve-existing-vcs-xml/test

@@ -0,0 +1,3 @@
+> update
+> idea
+> assert-expected-xml-files