Use instance creators only from single test file.

This ensures that ordering of tests does not influence
the initialization of the instance creators, assuming
this is done in the setup phase of the test.

Author: nhaarman

README.md

@@ -79,6 +79,9 @@ MockitoKotlin.registerInstanceCreator<MyClass> { MyClass(5) }
 Whenever MockitoKotlin needs to create an instance of `MyClass`, this function is called,
 giving you ultimate control over how these instances are created.
 
+These instance creators work on a per-file basis: for each of your test files
+you will need to register them again.
+
 ### Argument Matchers
 
 Using higher-order functions, you can write very clear expectations about expected values.

mockito-kotlin/src/main/kotlin/com/nhaarman/mockito_kotlin/MockitoKotlin.kt

@@ -35,7 +35,7 @@ class MockitoKotlin {
         /**
          * Maps KClasses to functions that can create an instance of that KClass.
          */
-        private val creators: MutableMap<KClass<*>, () -> Any> = HashMap()
+        private val creators: MutableMap<KClass<*>, MutableList<Pair<String, () -> Any>>> = HashMap()
 
         /**
          * Registers a function to be called when an instance of T is necessary.
@@ -45,7 +45,12 @@ class MockitoKotlin {
         /**
          * Registers a function to be called when an instance of T is necessary.
          */
-        fun <T : Any> registerInstanceCreator(kClass: KClass<T>, creator: () -> T) = creators.put(kClass, creator)
+        fun <T : Any> registerInstanceCreator(kClass: KClass<T>, creator: () -> T) {
+            val element = Error().stackTrace[1]
+
+            creators.getOrPut(kClass) { ArrayList<Pair<String, () -> Any>>() }
+                    .add(element.toFileIdentifier() to creator)
+        }
 
         /**
          * Unregisters an instance creator.
@@ -63,7 +68,16 @@ class MockitoKotlin {
         fun resetInstanceCreators() = creators.clear()
 
         internal fun <T : Any> instanceCreator(kClass: KClass<T>): (() -> Any)? {
+            val stacktrace = Error().stackTrace.filterNot {
+                it.className.contains("com.nhaarman.mockito_kotlin")
+            }[0]
+
             return creators[kClass]
+                    ?.filter { it.first == stacktrace.toFileIdentifier() }
+                    ?.firstOrNull()
+                    ?.second
         }
+
+        private fun StackTraceElement.toFileIdentifier() = "$fileName$className"
     }
 }