Discard unused nesting levels.

benchmark/before.dart.txt

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library pub.solver.backtracking_solver;
 
 import 'dart:async';
 import 'dart:collection' show Queue;
 
 import '../barback.dart' as barback;
@@ skipping 76 matching lines @@
 
     for (var override in root.dependencyOverrides) {
       _overrides[override.name] = override;
     }
 
     // A deeply nested statement that's hard on the formatter.
     isTwoWay = !isEvent && bindings.isWhole && (isCustomTag ||
         tag == 'input' && (name == 'value' || name =='checked') ||
         tag == 'select' && (name == 'selectedindex' || name == 'value') ||
         tag == 'textarea' && name == 'value');
+
+     // Even more deeply nested pathological example.
+     if (javaBooleanAnd(
+        javaBooleanAnd(
+            javaBooleanAnd(
+                javaBooleanAnd(
+                    javaBooleanAnd(
+                        javaBooleanAnd(
+                            javaBooleanAnd(
+                                javaBooleanAnd(),
+                                _isEqualTokens(
+                                    node.period,
+                                    toNode.period)),
+                            _isEqualNodes(
+                                node.name,
+                                toNode.name)),
+                        _isEqualNodes(
+                            node.parameters,
+                            toNode.parameters)),
+                    _isEqualTokens(
+                        node.separator,
+                        toNode.separator)),
+                _isEqualNodeLists(node.initializers, toNode.initializers)),
+            _isEqualNodes(
+                node.redirectedConstructor,
+                toNode.redirectedConstructor)),
+        _isEqualNodes(node.body, toNode.body))) {
+      toNode.element = node.element;
+    }
   }
 
   /// Run the solver.
   ///
   /// Completes with a list of specific package versions if successful or an
   /// error if it failed to find a solution.
   Future<SolveResult> solve() {
     var stopwatch = new Stopwatch();
 
     _logParameters();
@@ skipping 699 matching lines @@
 ///
 /// Throws a [SolveFailure] if not.
 void _validateSdkConstraint(Pubspec pubspec) {
   if (pubspec.environment.sdkVersion.allows(sdk.version)) return;
 
   throw new BadSdkVersionException(
       pubspec.name,
       'Package ${pubspec.name} requires SDK version '
           '${pubspec.environment.sdkVersion} but the current SDK is ' '${sdk.version}.');
 }