Find/replace overlay: Add tests for select-all and empty-search guard

The overlay's select-all operation (multi-selection of all occurrences,
storing the search term in history) and its refusal to replace while the
search string is empty were not covered by any test, so regressions in
these behaviors would go unnoticed. This adds according tests.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: HeikoKlare

tests/org.eclipse.ui.workbench.texteditor.tests/src/org/eclipse/ui/internal/findandreplace/overlay/FindReplaceOverlayTest.java

@@ -15,6 +15,7 @@
 
 import static org.eclipse.ui.internal.findandreplace.FindReplaceTestUtil.waitForFocus;
 import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
@@ -29,7 +30,10 @@
 
 import org.eclipse.text.tests.Accessor;
 
+import org.eclipse.jface.viewers.ISelection;
+
 import org.eclipse.jface.text.IFindReplaceTarget;
+import org.eclipse.jface.text.IMultiTextSelection;
 import org.eclipse.jface.text.TextViewer;
 
 import org.eclipse.ui.internal.findandreplace.FindReplaceUITest;
@@ -227,6 +231,49 @@ public void testSearchTermStoredInHistoryAfterSearchBackward() {
 		assertEquals("foo", dialog.getFindText());
 	}
 
+	@Test
+	public void testReplaceDoesNothingIfSearchStringIsEmpty() {
+		// The overlay refuses replace operations as long as the search string is
+		// empty; the document must remain unchanged.
+		initializeTextViewerWithFindReplaceUI("text text");
+		OverlayAccess dialog= getDialog();
+		dialog.setReplaceText("replacement");
+
+		dialog.performReplace();
+		assertThat(getTextViewer().getDocument().get(), is("text text"));
+
+		dialog.performReplaceAll();
+		assertThat(getTextViewer().getDocument().get(), is("text text"));
+	}
+
+	@Test
+	public void testSelectAllSelectsAllOccurrences() {
+		initializeTextViewerWithFindReplaceUI("foo bar foo bar foo");
+		OverlayAccess dialog= getDialog();
+		dialog.setFindText("foo");
+
+		dialog.pressSelectAll();
+
+		ISelection selection= getTextViewer().getSelection();
+		assertThat(selection, is(instanceOf(IMultiTextSelection.class)));
+		assertEquals(3, ((IMultiTextSelection) selection).getRegions().length);
+	}
+
+	@Test
+	public void testSearchTermStoredInHistoryAfterSelectAll() {
+		// Selecting all occurrences must persist the search term to history just
+		// like the other search operations.
+		initializeTextViewerWithFindReplaceUI("foo bar foo");
+		OverlayAccess dialog= getDialog();
+		dialog.setFindText("foo");
+		dialog.pressSelectAll();
+
+		dialog.setFindText("");
+		dialog.simulateKeyboardInteractionInFindInputField(SWT.ARROW_DOWN, false);
+
+		assertEquals("foo", dialog.getFindText());
+	}
+
 	@Test
 	public void testSearchInSelectionButtonIsInverseOfGlobalOption() {
 		// The searchInSelection button is the inverse of the GLOBAL option:

tests/org.eclipse.ui.workbench.texteditor.tests/src/org/eclipse/ui/internal/findandreplace/overlay/OverlayAccess.java

@@ -53,6 +53,8 @@ class OverlayAccess implements IFindReplaceUIAccess {
 
 	private final ToolItem searchBackward;
 
+	private final ToolItem selectAll;
+
 	private final ToolItem openReplaceDialog;
 
 	private HistoryTextWrapper replace;
@@ -74,6 +76,7 @@ class OverlayAccess implements IFindReplaceUIAccess {
 		inSelection= widgetExtractor.findToolItem("searchInSelection");
 		searchForward= widgetExtractor.findToolItem("searchForward");
 		searchBackward= widgetExtractor.findToolItem("searchBackward");
+		selectAll= widgetExtractor.findToolItem("selectAll");
 		openReplaceDialog= widgetExtractor.findToolItem("replaceToggle");
 		extractReplaceWidgets();
 	}
@@ -227,6 +230,10 @@ public void selectFindHistoryEntry(int index) {
 		}
 	}
 
+	public void pressSelectAll() {
+		selectAll.notifyListeners(SWT.Selection, null);
+	}
+
 	public void pressSearch(boolean forward) {
 		if (forward) {
 			searchForward.notifyListeners(SWT.Selection, null);