PY-18522 "Smart indent on paste" preserves original indent of statement if necessary

python/src/com/jetbrains/python/editor/PythonCopyPasteProcessor.java

@@ -162,8 +162,10 @@ public class PythonCopyPasteProcessor implements CopyPastePreProcessor {
           indentText = strings.get(0);
         }
       }
-      if (indentText.length() == firstLineIndent)
+      // Top-level, there should be no indentation
+      if (PsiTreeUtil.getParentOfType(ws, PyStatementList.class) == null) {
         return "";
+      }
     }
     return indentText;
   }

python/testData/copyPaste/SameIndentPreserved.after.py

@@ -0,0 +1,5 @@
+def f():
+    x = 1
+    z = 3
+
+    y = 2

python/testData/copyPaste/SameIndentPreserved.dst.py

@@ -0,0 +1,4 @@
+def f():
+    x = 1
+<caret>
+    y = 2

python/testData/copyPaste/SameIndentPreserved.src.py

@@ -0,0 +1,6 @@
+def f():
+    x = 1
+
+    y = 2
+<selection>    z = 3
+</selection>

python/testSrc/com/jetbrains/python/PyCopyPasteTest.java

@@ -371,4 +371,9 @@ public class PyCopyPasteTest extends PyTestCase {
   private void doTestMultiLine() {
     doTest("multiLine/");
   }
+
+  // PY-18522
+  public void testSameIndentPreserved() {
+    doTest();
+  }
 }