From 50a58a96781ea97d5cc45c45b3f573ba364d50e7 Mon Sep 17 00:00:00 2001
From: Sergey Simonchik <sergey.simonchik@jetbrains.com>
Date: Mon, 26 Mar 2018 17:41:28 +0300
Subject: [PATCH] add ComboBoxWithWidePopup#getMinimumPopupWidth to simplify
 API (IDEA-CR-31064)

---
 .../intellij/openapi/ui/ComboBoxWithWidePopup.java  | 13 ++++++++-----
 .../ide/ui/laf/darcula/ui/DarculaComboBoxUI.java    |  6 ++----
 2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/platform/platform-api/src/com/intellij/openapi/ui/ComboBoxWithWidePopup.java b/platform/platform-api/src/com/intellij/openapi/ui/ComboBoxWithWidePopup.java
index 313e6dddd8e2..e0ec1f6a11dc 100644
--- a/platform/platform-api/src/com/intellij/openapi/ui/ComboBoxWithWidePopup.java
+++ b/platform/platform-api/src/com/intellij/openapi/ui/ComboBoxWithWidePopup.java
@@ -69,12 +69,15 @@ public class ComboBoxWithWidePopup<E> extends JComboBox<E> {
   }
 
   /**
-   * @return original preferred size of JComboBox. E.g. its width naturally sets minimum
-   *         width of a wide popup as it's calculated as max of all pref sizes of combobox's items.
-   *         See {@link javax.swing.plaf.basic.BasicComboBoxUI#getDisplaySize()}.
+   * @return minimum width of a popup that is wide enough to show all the combobox's items horizontally
    */
-  public Dimension getOriginalPreferredSize() {
-    return super.getPreferredSize();
+  public int getMinimumPopupWidth() {
+    // Original preferred size of JComboBox is calculated as max of all pref sizes of combobox's items.
+    // See javax.swing.plaf.basic.BasicComboBoxUI#getDisplaySize()
+    //
+    // Please note that "getPreferredSize().width" cannot be used as getPreferredSize might be overridden
+    // to return a value different to "max of all pref sizes of comboBox's items".
+    return super.getPreferredSize().width;
   }
 
   private class AdjustingListCellRenderer implements ListCellRenderer<E> {
diff --git a/platform/platform-impl/src/com/intellij/ide/ui/laf/darcula/ui/DarculaComboBoxUI.java b/platform/platform-impl/src/com/intellij/ide/ui/laf/darcula/ui/DarculaComboBoxUI.java
index a79dd00676c0..28d33e8d03ba 100644
--- a/platform/platform-impl/src/com/intellij/ide/ui/laf/darcula/ui/DarculaComboBoxUI.java
+++ b/platform/platform-impl/src/com/intellij/ide/ui/laf/darcula/ui/DarculaComboBoxUI.java
@@ -514,12 +514,10 @@ public class DarculaComboBoxUI extends BasicComboBoxUI implements Border, ErrorB
     public void show(Component invoker, int x, int y) {
       if (comboBox instanceof ComboBoxWithWidePopup) {
         Dimension popupSize = comboBox.getSize();
-        // Can't use simply comboBox.getPreferredSize() as it can be overridden and implemented differently.
-        // Here we need max of all pref sizes of comboBox's items.
-        Dimension prefSize = ((ComboBoxWithWidePopup)comboBox).getOriginalPreferredSize();
+        int minPopupWidth = ((ComboBoxWithWidePopup)comboBox).getMinimumPopupWidth();
         Insets insets = getInsets();
 
-        popupSize.width = Math.max(popupSize.width, prefSize.width);
+        popupSize.width = Math.max(popupSize.width, minPopupWidth);
         popupSize.setSize(popupSize.width - (insets.right + insets.left), getPopupHeightForRowCount(comboBox.getMaximumRowCount()));
 
         scroller.setMaximumSize(popupSize);