IDEA-163049 "= ..." on selected item in completion list is confusing

java/java-impl/src/com/intellij/codeInsight/lookup/VariableLookupItem.java

@@ -45,6 +45,7 @@ import java.awt.*;
 * @author peter
 */
 public class VariableLookupItem extends LookupItem<PsiVariable> implements TypedLookupItem, StaticallyImportable {
+  private static final String EQ = " = ";
   @Nullable private final MemberLookupHelper myHelper;
   private final Color myColor;
   private final String myTailText;
@@ -77,7 +78,7 @@ public class VariableLookupItem extends LookupItem<PsiVariable> implements Typed
     String initText = initializer == null ? null : initializer.getText();
     if (StringUtil.isEmpty(initText)) return null;
 
-    String prefix = var instanceof PsiEnumConstant ? "" : " = ";
+    String prefix = var instanceof PsiEnumConstant ? "" : EQ;
     String suffix = var instanceof PsiEnumConstant && ((PsiEnumConstant)var).getInitializingClass() != null ? " {...}" : "";
     return StringUtil.trimLog(prefix + initText + suffix, 30);
   }
@@ -159,7 +160,11 @@ public class VariableLookupItem extends LookupItem<PsiVariable> implements Typed
       presentation.setTypeText(getType().getPresentableText());
     }
     if (myTailText != null && StringUtil.isEmpty(presentation.getTailText())) {
-      presentation.setTailText(myTailText, true);
+      if (myTailText.startsWith(EQ)) {
+        presentation.appendTailTextItalic(" (" + myTailText + ")", true);
+      } else {
+        presentation.setTailText(myTailText, true);
+      }
     }
   }
 

java/java-tests/testSrc/com/intellij/codeInsight/completion/JavaAutoPopupTest.groovy

@@ -1448,7 +1448,7 @@ class Foo {{
     def constant = myFixture.lookupElements.find { it.lookupString == 'Util.CONSTANT' }
     LookupElementPresentation p = ApplicationManager.application.runReadAction ({ LookupElementPresentation.renderElement(constant) } as Computable<LookupElementPresentation>)
     assert p.itemText == 'Util.CONSTANT'
-    assert p.tailText == ' = 2 (foo)'
+    assert p.tailText == ' ( = 2) (foo)'
     assert p.typeText == 'int'
 
     type 'fo\n'

java/java-tests/testSrc/com/intellij/codeInsight/completion/NormalCompletionTest.groovy

@@ -1707,7 +1707,8 @@ class Bar {
     assert LookupElementPresentation.renderElement(myFixture.lookup.items[0]).tailText == '( "x")'
     assert LookupElementPresentation.renderElement(myFixture.lookup.items[1]).tailText == '("y") {...}'
     assert !LookupElementPresentation.renderElement(myFixture.lookup.items[2]).tailText
-    assert LookupElementPresentation.renderElement(myFixture.lookup.items[3]).tailText == ' = 42'
+    assert LookupElementPresentation.renderElement(myFixture.lookup.items[3]).tailText == ' ( = 42)'
+    assert LookupElementPresentation.renderElement(myFixture.lookup.items[3]).tailFragments[0].italic
   }
 
   void testSuggestInterfaceArrayWhenObjectIsExpected() {

platform/lang-api/src/com/intellij/codeInsight/lookup/LookupElementPresentation.java

@@ -17,7 +17,6 @@ package com.intellij.codeInsight.lookup;
 
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.ui.JBColor;
-import com.intellij.util.Function;
 import com.intellij.util.SmartList;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -67,7 +66,11 @@ public class LookupElementPresentation {
   }
 
   public void appendTailText(@NotNull String text, boolean grayed) {
-    appendTailText(new TextFragment(text, grayed, null));
+    appendTailText(new TextFragment(text, grayed, false, null));
+  }
+
+  public void appendTailTextItalic(@NotNull String text, boolean grayed) {
+    appendTailText(new TextFragment(text, grayed, true, null));
   }
 
   private void appendTailText(@NotNull TextFragment fragment) {
@@ -80,14 +83,14 @@ public class LookupElementPresentation {
   public void setTailText(@Nullable String text, boolean grayed) {
     clearTail();
     if (text != null) {
-      appendTailText(new TextFragment(text, grayed, null));
+      appendTailText(new TextFragment(text, grayed, false, null));
     }
   }
 
   public void setTailText(@Nullable String text, @Nullable Color foreground) {
     clearTail();
     if (text != null) {
-      appendTailText(new TextFragment(text, false, foreground));
+      appendTailText(new TextFragment(text, false, false, foreground));
     }
   }
 
@@ -101,7 +104,7 @@ public class LookupElementPresentation {
   }
 
   /**
-   * Is equivalent to instanceof {@link com.intellij.codeInsight.lookup.RealLookupElementPresentation} check.
+   * Is equivalent to instanceof {@link RealLookupElementPresentation} check.
    *
    * @return whether the presentation is requested to actually render lookup element on screen, or just to estimate its width.
    * In the second, 'non-real' case, some heavy operations (e.g. getIcon()) can be omitted (only icon width is important)
@@ -127,7 +130,7 @@ public class LookupElementPresentation {
 
   @NotNull
   public List<TextFragment> getTailFragments() {
-    return myTail == null ? Collections.<TextFragment>emptyList() : Collections.unmodifiableList(myTail);
+    return myTail == null ? Collections.emptyList() : Collections.unmodifiableList(myTail);
   }
 
   @Nullable
@@ -147,13 +150,13 @@ public class LookupElementPresentation {
 
   @Deprecated
   public boolean isTailGrayed() {
-    return myTail != null && myTail.get(0).grayed;
+    return myTail != null && myTail.get(0).myGrayed;
   }
 
   @Nullable
   @Deprecated
   public Color getTailForeground() {
-    return myTail != null ? myTail.get(0).fgColor : null;
+    return myTail != null ? myTail.get(0).myFgColor : null;
   }
 
   public boolean isItemTextBold() {
@@ -217,31 +220,37 @@ public class LookupElementPresentation {
 
   public static class TextFragment {
     public final String text;
-    private final boolean grayed;
-    @Nullable private final Color fgColor;
+    private final boolean myGrayed;
+    private final boolean myItalic;
+    @Nullable private final Color myFgColor;
 
-    public TextFragment(String text, boolean grayed, @Nullable Color fgColor) {
+    private TextFragment(String text, boolean grayed, boolean italic, @Nullable Color fgColor) {
       this.text = text;
-      this.grayed = grayed;
-      this.fgColor = fgColor;
+      myGrayed = grayed;
+      myItalic = italic;
+      myFgColor = fgColor;
     }
 
     @Override
     public String toString() {
       return "TextFragment{" +
              "text='" + text + '\'' +
-             ", grayed=" + grayed +
-             ", fgColor=" + fgColor +
+             ", grayed=" + myGrayed +
+             ", fgColor=" + myFgColor +
              '}';
     }
 
     public boolean isGrayed() {
-      return grayed;
+      return myGrayed;
+    }
+
+    public boolean isItalic() {
+      return myItalic;
     }
 
     @Nullable
     public Color getForegroundColor() {
-      return fgColor;
+      return myFgColor;
     }
   }
 }

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

@@ -266,7 +266,8 @@ public class LookupCellRenderer implements ListCellRenderer {
       }
 
       String trimmed = trimLabelText(fragment.text, allowedWidth, fontMetrics);
-      myTailComponent.append(trimmed, new SimpleTextAttributes(style, getTailTextColor(isSelected, fragment, foreground, nonFocusedSelection)));
+      int fragmentStyle = fragment.isItalic() ? style | SimpleTextAttributes.STYLE_ITALIC : style;
+      myTailComponent.append(trimmed, new SimpleTextAttributes(fragmentStyle, getTailTextColor(isSelected, fragment, foreground, nonFocusedSelection)));
       allowedWidth -= RealLookupElementPresentation.getStringWidth(trimmed, fontMetrics);
     }
   }