Copy: Support multiple classes in the same file

idea/testData/refactoring/copy/copyMultipleClassesToExistingFile/after/bar/test.kt

@@ -0,0 +1,19 @@
+package bar
+
+import foo.B
+
+fun test() {
+
+}
+
+class A {
+    val a: A = A()
+    val b: B = B()
+    val c: C = C()
+}
+
+class C {
+    val a: A = A()
+    val b: B = B()
+    val c: C = C()
+}

idea/testData/refactoring/copy/copyMultipleClassesToExistingFile/after/foo/test.kt

@@ -0,0 +1,19 @@
+package foo
+
+class A {
+    val a: A = A()
+    val b: B = B()
+    val c: C = C()
+}
+
+class B {
+    val a: A = A()
+    val b: B = B()
+    val c: C = C()
+}
+
+class C {
+    val a: A = A()
+    val b: B = B()
+    val c: C = C()
+}

idea/testData/refactoring/copy/copyMultipleClassesToExistingFile/before/bar/test.kt

@@ -0,0 +1,5 @@
+package bar
+
+fun test() {
+
+}

idea/testData/refactoring/copy/copyMultipleClassesToExistingFile/before/foo/test.kt

@@ -0,0 +1,19 @@
+package foo
+
+class <caret>A {
+    val a: A = A()
+    val b: B = B()
+    val c: C = C()
+}
+
+class B {
+    val a: A = A()
+    val b: B = B()
+    val c: C = C()
+}
+
+class <caret>C {
+    val a: A = A()
+    val b: B = B()
+    val c: C = C()
+}

idea/testData/refactoring/copy/copyMultipleClassesToExistingFile/copyMultipleClassesToExistingFile.test

@@ -0,0 +1,4 @@
+{
+  "mainFile": "foo/test.kt",
+  "targetPackage": "bar"
+}