ensure that non-customized lookup items have identical icon height (16) so that the lookup height remains constant while typing

platform/lang-impl/src/com/intellij/codeInsight/lookup/DefaultLookupItemRenderer.java

@@ -19,6 +19,7 @@ import com.intellij.openapi.util.Iconable;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.meta.PsiMetaData;
 import com.intellij.psi.util.PsiUtilBase;
+import com.intellij.ui.TruncatingIcon;
 import com.intellij.util.Icons;
 import com.intellij.util.ui.EmptyIcon;
 import org.jetbrains.annotations.Nullable;
@@ -44,6 +45,15 @@ public class DefaultLookupItemRenderer extends LookupElementRenderer<LookupItem>
 
   @Nullable
   public static Icon getRawIcon(final LookupItem item, boolean real) {
+    final Icon icon = _getRawIcon(item, real);
+    if (icon != null && icon.getIconHeight() > SAMPLE_ICON.getIconHeight()) {
+      return new TruncatingIcon(icon, icon.getIconWidth(), SAMPLE_ICON.getIconHeight());
+    }
+    return icon;
+  }
+
+  @Nullable
+  private static Icon _getRawIcon(LookupItem item, boolean real) {
     Icon icon = (Icon)item.getAttribute(LookupItem.ICON_ATTR);
     if (icon != null) return icon;
 
@@ -73,7 +83,7 @@ public class DefaultLookupItemRenderer extends LookupElementRenderer<LookupItem>
     }
     return null;
   }
-  
+
 
   @Nullable
   private static String getText3(final LookupItem item) {

platform/lang-impl/src/com/intellij/codeInsight/lookup/impl/LookupCellRenderer.java

@@ -25,7 +25,7 @@ import com.intellij.openapi.editor.colors.EditorColorsManager;
 import com.intellij.openapi.editor.colors.EditorColorsScheme;
 import com.intellij.openapi.editor.colors.EditorFontType;
 import com.intellij.openapi.util.text.StringUtil;
-import com.intellij.ui.RowIcon;
+import com.intellij.ui.LayeredIcon;
 import com.intellij.ui.SimpleColoredComponent;
 import com.intellij.ui.SimpleTextAttributes;
 import com.intellij.ui.popup.PopupIcons;
@@ -280,11 +280,11 @@ public class LookupCellRenderer implements ListCellRenderer {
       return myEmptyIcon;
     }
 
-    if (icon.getIconWidth() < myEmptyIcon.getIconWidth()) {
-      final RowIcon rowIcon = new RowIcon(2);
-      rowIcon.setIcon(icon, 0);
-      rowIcon.setIcon(new EmptyIcon(myEmptyIcon.getIconWidth() - icon.getIconWidth()), 1);
-      return rowIcon;
+    if (icon.getIconHeight() < myEmptyIcon.getIconHeight() || icon.getIconWidth() < myEmptyIcon.getIconWidth()) {
+      final LayeredIcon layeredIcon = new LayeredIcon(2);
+      layeredIcon.setIcon(icon, 0, 0, (myEmptyIcon.getIconHeight() - icon.getIconHeight()) / 2);
+      layeredIcon.setIcon(myEmptyIcon, 1);
+      return layeredIcon;
     }
 
     return icon;
@@ -294,8 +294,8 @@ public class LookupCellRenderer implements ListCellRenderer {
     final LookupElementPresentation p = new LookupElementPresentation();
     item.renderElement(p);
     final Icon icon = p.getIcon();
-    if (icon != null && icon.getIconWidth() > myEmptyIcon.getIconWidth()) {
-      myEmptyIcon = new EmptyIcon(icon.getIconWidth(), 2);
+    if (icon != null && (icon.getIconWidth() > myEmptyIcon.getIconWidth() || icon.getIconHeight() > myEmptyIcon.getIconHeight())) {
+      myEmptyIcon = new EmptyIcon(Math.max(icon.getIconWidth(), myEmptyIcon.getIconWidth()), Math.max(icon.getIconHeight(), myEmptyIcon.getIconHeight()));
     }
 
     int maxWidth = Math.min(RealLookupElementPresentation.calculateWidth(p, myNormalMetrics, myBoldMetrics), myMaxWidth);

platform/platform-api/src/com/intellij/ui/TruncatingIcon.java

@@ -0,0 +1,31 @@
+package com.intellij.ui;
+
+import javax.swing.*;
+import java.awt.*;
+
+/**
+ * @author peter
+ */
+public class TruncatingIcon implements Icon {
+  private final int myWidth;
+  private final int myHeight;
+  private final Icon myDelegate;
+
+  public TruncatingIcon(Icon delegate, int width, int height) {
+    myDelegate = delegate;
+    myWidth = width;
+    myHeight = height;
+  }
+
+  public void paintIcon(Component c, Graphics g, int x, int y) {
+    myDelegate.paintIcon(c, g, x, y);
+  }
+
+  public int getIconWidth() {
+    return myWidth;
+  }
+
+  public int getIconHeight() {
+    return myHeight;
+  }
+}