lazy toString renderer, not enabled for now

java/debugger/impl/src/com/intellij/debugger/engine/JavaValue.java

@@ -306,6 +306,9 @@ public class JavaValue extends XNamedValue implements NodeDescriptorProvider, XV
           lastRenderer = ((CompoundTypeRenderer)lastRenderer).getLabelRenderer();
         }
         if (lastRenderer instanceof ToStringRenderer) {
+          if (lastRenderer instanceof LazyToStringRenderer && !((LazyToStringRenderer)lastRenderer).isCalculated(myValueDescriptor)) {
+            return;
+          }
           value = StringUtil.wrapWithDoubleQuote(value);
         }
         renderer.renderValue(value);

java/debugger/impl/src/com/intellij/debugger/ui/tree/render/LazyToStringRenderer.kt

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2000-2017 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.debugger.ui.tree.render
+
+import com.intellij.debugger.DebuggerBundle
+import com.intellij.debugger.engine.FullValueEvaluatorProvider
+import com.intellij.debugger.engine.evaluation.EvaluateException
+import com.intellij.debugger.engine.evaluation.EvaluationContext
+import com.intellij.debugger.engine.evaluation.EvaluationContextImpl
+import com.intellij.debugger.ui.impl.watch.ValueDescriptorImpl
+import com.intellij.debugger.ui.tree.ValueDescriptor
+import com.intellij.openapi.util.Key
+import com.intellij.xdebugger.frame.XFullValueEvaluator
+import com.intellij.xdebugger.frame.XValuePlace
+import com.intellij.xdebugger.impl.ui.tree.nodes.HeadlessValueEvaluationCallback
+
+/**
+ * @author egor
+ */
+class LazyToStringRenderer : ToStringRenderer(), FullValueEvaluatorProvider {
+  init {
+    isEnabled = true
+  }
+
+  override fun getFullValueEvaluator(evaluationContext: EvaluationContextImpl?, valueDescriptor: ValueDescriptorImpl): XFullValueEvaluator? {
+    if (!isCalculated(valueDescriptor)) {
+      return object : XFullValueEvaluator(DebuggerBundle.message("message.node.toString")) {
+        override fun startEvaluation(callback: XFullValueEvaluator.XFullValueEvaluationCallback) {
+          if (callback is HeadlessValueEvaluationCallback) {
+            val node = callback.node
+            node.clearFullValueEvaluator()
+            valueDescriptor.putUserData(LAZY_CALCULATED, true)
+            node.valueContainer.computePresentation(node, XValuePlace.TREE)
+          }
+          callback.evaluated("")
+        }
+      }.setShowValuePopup(false)
+    }
+    return null
+  }
+
+  @Throws(EvaluateException::class)
+  override fun calcLabel(descriptor: ValueDescriptor, evaluationContext: EvaluationContext, listener: DescriptorLabelListener): String? {
+    if (!isCalculated(descriptor)) {
+      return ""
+    }
+    return super.calcLabel(descriptor, evaluationContext, listener)
+  }
+
+  fun isCalculated(descriptor: ValueDescriptor): Boolean {
+    return java.lang.Boolean.TRUE == descriptor.getUserData(LAZY_CALCULATED)
+  }
+
+  override fun getName(): String {
+    return "Lazy" + super.getName()
+  }
+
+  override fun getUniqueId(): String {
+    return "Lazy" + super.getUniqueId()
+  }
+
+  companion object {
+    private val LAZY_CALCULATED = Key.create<Boolean>("LAZY_CALCULATED")
+  }
+}

platform/xdebugger-impl/src/com/intellij/xdebugger/impl/ui/tree/nodes/HeadlessValueEvaluationCallback.java

@@ -1,3 +1,18 @@
+/*
+ * Copyright 2000-2017 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 package com.intellij.xdebugger.impl.ui.tree.nodes;
 
 import com.intellij.notification.NotificationType;
@@ -64,6 +79,10 @@ public class HeadlessValueEvaluationCallback implements XFullValueEvaluator.XFul
     }
   }
 
+  public XValueNodeImpl getNode() {
+    return myNode;
+  }
+
   protected void evaluationComplete(@NotNull String value, @NotNull Project project) {
 
   }

platform/xdebugger-impl/src/com/intellij/xdebugger/impl/ui/tree/nodes/XValueNodeImpl.java

@@ -173,6 +173,10 @@ public class XValueNodeImpl extends XValueContainerNode<XValue> implements XValu
     });
   }
 
+  public void clearFullValueEvaluator() {
+    myFullValueEvaluator = null;
+  }
+
   private void updateText() {
     myText.clear();
     XValueMarkers<?, ?> markers = myTree.getValueMarkers();

resources-en/src/messages/DebuggerBundle.properties

@@ -428,6 +428,7 @@ message.node.evaluation.not.possible=Target VM is not paused by breakpoint reque
 message.node.show.image=\u2026 Show image
 message.node.show.icon=\u2026 Show icon
 message.node.navigate=\u2026 Navigate
+message.node.toString=\u2026 toString
 label.thread.node.thread.collected=Thread ''{0}'' has been garbage-collected
 label.thread.node=\"{0}\"@{1}: {2}
 label.thread.node.in.group=\"{0}\"@{1} in group \"{3}\": {2}