SearchResultWidget: Disable replace button if replace text is unchanged

To avoid unneeded file rename operations when the "Rename x files"
checkbox is checked.

Change-Id: I3fc8b1607979bdfcdd7a3f2d3cf172350f7ca758
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/coreplugin/find/searchresultwidget.cpp

@@ -210,6 +210,8 @@ SearchResultWidget::SearchResultWidget(QWidget *parent) :
             this, &SearchResultWidget::handleReplaceButton);
     connect(m_replaceButton, &QAbstractButton::clicked,
             this, &SearchResultWidget::handleReplaceButton);
+    connect(m_replaceTextEdit, &QLineEdit::textChanged,
+            this, &SearchResultWidget::handleReplaceEditTextChanged);
 }
 
 SearchResultWidget::~SearchResultWidget()
@@ -304,6 +306,7 @@ void SearchResultWidget::setSupportsReplace(bool replaceSupported, const QString
 
 void SearchResultWidget::setTextToReplace(const QString &textToReplace)
 {
+    m_replaceText = textToReplace;
     m_replaceTextEdit->setText(textToReplace);
 }
 
@@ -406,7 +409,6 @@ void SearchResultWidget::goToPrevious()
 void SearchResultWidget::restart()
 {
     m_replaceTextEdit->setEnabled(false);
-    m_replaceButton->setEnabled(false);
     m_searchResultTreeView->clear();
     m_count = 0;
     Id sizeWarningId(SIZE_WARNING_ID);
@@ -416,6 +418,7 @@ void SearchResultWidget::restart()
     m_searchAgainButton->setVisible(false);
     m_messageWidget->setVisible(false);
     updateMatchesFoundLabel();
+    handleReplaceEditTextChanged();
     emit restarted();
 }
 
@@ -436,7 +439,6 @@ void SearchResultWidget::finishSearch(bool canceled)
     m_infoBar.removeInfo(sizeWarningId);
     m_infoBar.enableInfo(sizeWarningId);
     m_replaceTextEdit->setEnabled(m_count > 0);
-    m_replaceButton->setEnabled(m_count > 0);
     m_preserveCaseCheck->setEnabled(m_count > 0);
     m_cancelButton->setVisible(false);
     m_messageWidget->setVisible(canceled);
@@ -461,6 +463,15 @@ void SearchResultWidget::cancelAfterSizeWarning()
     emit paused(false);
 }
 
+void SearchResultWidget::handleReplaceEditTextChanged()
+{
+    const bool enabled = m_replaceTextEdit->text() != m_replaceText;
+    m_replaceButton->setEnabled(enabled);
+    m_replaceButton->setToolTip(enabled
+                                ? QString()
+                                : tr("Cannot replace because replacement text is unchanged."));
+}
+
 void SearchResultWidget::handleJumpToSearchResult(const SearchResultItem &item)
 {
     emit activated(item);

src/plugins/coreplugin/find/searchresultwidget.h

@@ -115,6 +115,7 @@ private:
     void setShowReplaceUI(bool visible);
     void continueAfterSizeWarning();
     void cancelAfterSizeWarning();
+    void handleReplaceEditTextChanged();
 
     QList<SearchResultItem> checkedItems() const;
     void updateMatchesFoundLabel();
@@ -141,6 +142,7 @@ private:
     bool m_isShowingReplaceUI = false;
     bool m_searchAgainSupported = false;
     bool m_replaceSupported = false;
+    QString m_replaceText;
 };
 
 } // Internal