better alignment in nested binary expressions (PY-5710)

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

@@ -28,6 +28,7 @@ import static com.jetbrains.python.psi.PyUtil.sure;
  * @author yole
  */
 public class PyBlock implements ASTBlock {
+  private final PyBlock myParent;
   private final Alignment _alignment;
   private final Indent _indent;
   private final ASTNode _node;
@@ -54,11 +55,13 @@ public class PyBlock implements ASTBlock {
                                                               PyTokenTypes.LBRACE, PyTokenTypes.RBRACE,
                                                               PyTokenTypes.LBRACKET, PyTokenTypes.RBRACKET);
 
-  public PyBlock(final ASTNode node,
+  public PyBlock(final PyBlock parent,
+                 final ASTNode node,
                  final Alignment alignment,
                  final Indent indent,
                  final Wrap wrap,
                  final PyBlockContext context) {
+    myParent = parent;
     _alignment = alignment;
     _indent = indent;
     _node = node;
@@ -134,8 +137,13 @@ public class PyBlock implements ASTBlock {
       }
     }
     else if (parentType == PyElementTypes.BINARY_EXPRESSION &&
-             PythonDialectsTokenSetProvider.INSTANCE.getExpressionTokens().contains(childType)) {
-      childAlignment = getAlignmentForChildren();
+             (PythonDialectsTokenSetProvider.INSTANCE.getExpressionTokens().contains(childType) || PyTokenTypes.OPERATIONS.contains(childType))) {
+      if (grandparentType == PyElementTypes.BINARY_EXPRESSION && myParent != null) {
+        childAlignment = myParent.getAlignmentForChildren();
+      }
+      else {
+        childAlignment = getAlignmentForChildren();
+      }
     }
 
     if (parentType == PyElementTypes.LIST_LITERAL_EXPRESSION) {
@@ -190,7 +198,7 @@ public class PyBlock implements ASTBlock {
       childIndent = Indent.getNormalIndent();
     }
 
-    return new PyBlock(child, childAlignment, childIndent, wrap, myContext);
+    return new PyBlock(this, child, childAlignment, childIndent, wrap, myContext);
   }
 
   private static boolean isEmptyList(PsiElement psi) {

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

@@ -35,7 +35,7 @@ public class PythonFormattingModelBuilder implements FormattingModelBuilderEx, C
     }
     final CommonCodeStyleSettings codeStyleSettings = settings.getCommonSettings(PythonLanguage.getInstance());
     final PyBlockContext context = new PyBlockContext(codeStyleSettings, createSpacingBuilder(settings), mode);
-    final PyBlock block = new PyBlock(element.getNode(), null, Indent.getNoneIndent(), null, context);
+    final PyBlock block = new PyBlock(null, element.getNode(), null, Indent.getNoneIndent(), null, context);
     if (DUMP_FORMATTING_AST) {
       FormattingModelDumper.dumpFormattingModel(block, 2, System.out);
     }

python/testData/formatter/alignInBinaryExpressions.py

@@ -0,0 +1,3 @@
+term1 = BNF.lpar + expr + BNF.rpar\
+| if_expr\
+| numeric_value

python/testData/formatter/alignInBinaryExpressions_after.py

@@ -0,0 +1,3 @@
+term1 = BNF.lpar + expr + BNF.rpar\
+        | if_expr\
+        | numeric_value

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

@@ -167,6 +167,10 @@ public class PyFormatterTest extends PyTestCase {
     doTest();
   }
 
+  public void testAlignInBinaryExpressions() {
+    doTest();
+  }
+
   public void testPsiFormatting() { // IDEA-69724
     String initial =
       "def method_name(\n" +