PY-16335 Preserve formatting of converted collection literals

python/src/com/jetbrains/python/codeInsight/intentions/PyBaseConvertCollectionLiteralIntention.java

@@ -98,16 +98,17 @@ public abstract class PyBaseConvertCollectionLiteralIntention extends BaseIntent
       replacedElement = literal;
     }
 
+    final String innerText = stripLiteralBraces(replacedElement);
     final PyElementGenerator elementGenerator = PyElementGenerator.getInstance(project);
     final PyExpression newLiteral = elementGenerator.createExpressionFromText(LanguageLevel.forElement(file),
-                                                                              myLeftBrace + stripLiteralBraces(literal) + myRightBrace);
+                                                                              myLeftBrace + innerText + myRightBrace);
     replacedElement.replace(newLiteral);
   }
 
   @NotNull
-  private static String stripLiteralBraces(@NotNull PySequenceExpression literal) {
+  private static String stripLiteralBraces(@NotNull PsiElement literal) {
     if (literal instanceof PyTupleExpression) {
-      return literal.getText().trim();
+      return literal.getText();
     }
 
     final PsiElement firstChild = literal.getFirstChild();
@@ -130,7 +131,7 @@ public abstract class PyBaseConvertCollectionLiteralIntention extends BaseIntent
       contentEndOffset = replacedText.length();
     }
 
-    return literal.getText().substring(contentStartOffset, contentEndOffset).trim();
+    return literal.getText().substring(contentStartOffset, contentEndOffset);
   }
 
   @Nullable

python/testData/intentions/PyConvertCollectionLiteralIntentionTest/convertLiteralPreservesFormattingAndComments.py

@@ -0,0 +1,4 @@
+xs = (<caret>
+    1, 2,  # comment 1
+    3  # comment 2
+)

python/testData/intentions/PyConvertCollectionLiteralIntentionTest/convertLiteralPreservesFormattingAndComments_after.py

@@ -0,0 +1,4 @@
+xs = [
+    1, 2,  # comment 1
+    3  # comment 2
+]

python/testSrc/com/jetbrains/python/intentions/PyConvertCollectionLiteralIntentionTest.java

@@ -103,4 +103,9 @@ public class PyConvertCollectionLiteralIntentionTest extends PyIntentionTestCase
   public void testConvertSetToList() {
     doIntentionTest(CONVERT_SET_TO_LIST);
   }
+
+  // PY-16335
+  public void testConvertLiteralPreservesFormattingAndComments() {
+    doIntentionTest(CONVERT_TUPLE_TO_LIST);
+  }
 }