failing test for alignment in binary expressions

python/src/com/jetbrains/python/formatter/PyBlock.java

@@ -33,7 +33,7 @@ public class PyBlock implements ASTBlock {
   private final Wrap _wrap;
   private final CodeStyleSettings mySettings;
   private List<PyBlock> _subBlocks = null;
-  private final Alignment _childListAlignment;
+  private Alignment myChildAlignment;
   private static final boolean DUMP_FORMATTING_BLOCKS = false;
 
   private static final TokenSet ourListElementTypes = TokenSet.create(PyElementTypes.LIST_LITERAL_EXPRESSION,
@@ -61,7 +61,6 @@ public class PyBlock implements ASTBlock {
     _node = node;
     _wrap = wrap;
     mySettings = settings;
-    _childListAlignment = Alignment.createAlignment();
   }
 
   @NotNull
@@ -74,6 +73,13 @@ public class PyBlock implements ASTBlock {
     return _node.getTextRange();
   }
 
+  private Alignment getAlignmentForChildren() {
+    if (myChildAlignment == null) {
+      myChildAlignment = Alignment.createAlignment();
+    }
+    return myChildAlignment;
+  }
+
   @NotNull
   public List<Block> getSubBlocks() {
     if (_subBlocks == null) {
@@ -131,9 +137,12 @@ public class PyBlock implements ASTBlock {
         wrap = Wrap.createWrap(WrapType.NORMAL, true);
       }
       if (needListAlignment(child)) {
-        childAlignment = _childListAlignment;
+        childAlignment = getAlignmentForChildren();
       }
     }
+    else if (parentType == PyElementTypes.BINARY_EXPRESSION && PyElementTypes.EXPRESSIONS.contains(childType)) {
+      childAlignment = getAlignmentForChildren();
+    }
     if (parentType == PyElementTypes.LIST_LITERAL_EXPRESSION) {
       if (childType == PyTokenTypes.RBRACKET || childType == PyTokenTypes.LBRACKET) {
         childIndent = Indent.getNoneIndent();
@@ -452,7 +461,7 @@ public class PyBlock implements ASTBlock {
 
   private Alignment getChildAlignment() {
     if (ourListElementTypes.contains(_node.getElementType())) {
-      return _childListAlignment;
+      return getAlignmentForChildren();
     }
     return null;
   }

python/testData/formatter/alignInBinaryExpression.py

@@ -0,0 +1,2 @@
+if isintance(True, bool) and\
+    isinstance(1, int): pass

python/testData/formatter/alignInBinaryExpression_after.py

@@ -0,0 +1,2 @@
+if isintance(True, bool) and\
+   isinstance(1, int): pass

python/testSrc/com/jetbrains/python/PyFormatterTest.java

@@ -76,6 +76,10 @@ public class PyFormatterTest extends PyLightFixtureTestCase {
     doTest();
   }
 
+  public void testAlignInBinaryExpression() {
+    doTest();
+  }
+
   private void doTest() {
     myFixture.configureByFile("formatter/" + getTestName(true) + ".py");
     ApplicationManager.getApplication().runWriteAction(new Runnable() {