when joining comments, we skipped over whitespace to the left of caret twice, which caused characters to be deleted (PY-7286)

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

@@ -420,11 +420,7 @@ public class PyJoinLinesHandler implements JoinRawLinesHandlerDelegate {
         int last = right_range.getEndOffset();
         while (pos < last && " \t".indexOf(text.charAt(pos)) >= 0) pos += 1;
         int right = pos - initial_pos + 1; // account for the '#'
-        initial_pos = req.leftElem().getTextRange().getEndOffset() - 1;
-        pos = initial_pos;
-        while (" \t".indexOf(text.charAt(pos)) >= 0) pos -=1; // we'll end up at '#' if nothing else
-        int left = initial_pos - pos;
-        return new Result(" ", 0, left, right);
+        return new Result(" ", 0, 0, right);
       }
       return null;
     }

python/testData/joinLines/TwoComments2-after.py

@@ -0,0 +1 @@
+        # has the

python/testData/joinLines/TwoComments2.py

@@ -0,0 +1,2 @@
+        # has <caret>
+        # the

python/testSrc/com/jetbrains/python/PyJoinLinesTest.java

@@ -61,6 +61,7 @@ public class PyJoinLinesTest extends PyTestCase {
   public void testTuple() { doTest(); }
   public void testTupleRPar() { doTest(); }
   public void testTwoComments() { doTest(); }
+  public void testTwoComments2() { doTest(); }   // PY-7286
   public void testTwoStatements() { doTest(); }
   public void testStringWithSlash() { doTest(); }
   public void testListOfStrings() { doTest(); }

python/testSrc/com/jetbrains/python/PythonAllTestsSuite.java

@@ -98,7 +98,8 @@ public class PythonAllTestsSuite {
     PyMissingConstructorTest.class,
     PyPropertyAccessInspectionTest.class,
     Jinja2ParserTest.class,
-    DjangoTemplateParserTest.class
+    DjangoTemplateParserTest.class,
+    PyJoinLinesTest.class
   };
 
   public static TestSuite suite() {