Grid editor: TAB now skips non-editable columns (#11573)

* Grid editor: TAB now skips non-editable columns

Pressing TAB would shift the focus to non-editable cells when the Grid was in edit mode.
This patch makes DefaultEditorEventHandler to skip such columns.

Closes #10970

* Add tests

2 files changed, 232 insertions, 0 deletions

diff --git a/uitest/src/main/java/com/vaadin/tests/components/grid/GridEditorTabSkipsNonEditableCells.java b/uitest/src/main/java/com/vaadin/tests/components/grid/GridEditorTabSkipsNonEditableCells.java
new file mode 100644
index 0000000000..cf8c673c09
--- /dev/null
+++ b/uitest/src/main/java/com/vaadin/tests/components/grid/GridEditorTabSkipsNonEditableCells.java
@@ -0,0 +1,102 @@
+package com.vaadin.tests.components.grid;
+
+import com.vaadin.annotations.Widgetset;
+import com.vaadin.data.provider.ListDataProvider;
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.tests.components.AbstractTestUI;
+import com.vaadin.ui.Button;
+import com.vaadin.ui.Grid;
+import com.vaadin.ui.TextField;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Shows a Grid with the only editable columns being the column 1 and 3. That
+ * will allow us to test that Tab/Shift+Tab skips cells that are not editable.
+ */
+@Widgetset("com.vaadin.DefaultWidgetSet")
+public class GridEditorTabSkipsNonEditableCells extends AbstractTestUI {
+
+    @Override
+    protected void setup(VaadinRequest request) {
+        final List<TestBean> items = new ArrayList<>();
+        Grid<TestBean> grid = new Grid<TestBean>(TestBean.class);
+        for (int i = 0; i < 10; i++) {
+            items.add(new TestBean(i));
+        }
+        grid.setDataProvider(new ListDataProvider<>(items));
+        grid.setWidth("100%");
+        grid.setHeight("400px");
+        grid.getEditor().setEnabled(true);
+        grid.getColumn("col1").setEditorComponent(new TextField());
+        grid.getColumn("col3").setEditorComponent(new TextField());
+        grid.setColumnOrder("col0", "col1", "col2", "col3", "col4");
+
+        getLayout().addComponent(
+                new Button("Set Editor Buffered Mode On", event -> {
+                    grid.getEditor().cancel();
+                    grid.getEditor().setBuffered(true);
+                }));
+        getLayout().addComponent(
+                new Button("Set Editor Buffered Mode Off", event -> {
+                    grid.getEditor().cancel();
+                    grid.getEditor().setBuffered(false);
+                }));
+
+        getLayout().addComponent(grid);
+    }
+
+    @Override
+    protected Integer getTicketNumber() {
+        return 11573;
+    }
+
+    @Override
+    protected String getTestDescription() {
+        return "Pressing TAB doesn't shift the focus to non-editable cells when the Grid is in edit mode.";
+    }
+
+    public class TestBean {
+        private final int row;
+
+        public TestBean(int row) {
+            this.row = row;
+        }
+
+        public String getCol0() {
+            return "col0_" + row;
+        }
+
+        public String getCol1() {
+            return "col1_" + row;
+        }
+
+        public String getCol2() {
+            return "col2_" + row;
+        }
+
+        public String getCol3() {
+            return "col3_" + row;
+        }
+
+        public String getCol4() {
+            return "col4_" + row;
+        }
+
+        public void setCol0(String value) {
+        }
+
+        public void setCol1(String value) {
+        }
+
+        public void setCol2(String value) {
+        }
+
+        public void setCol3(String value) {
+        }
+
+        public void setCol4(String value) {
+        }
+    }
+}
diff --git a/uitest/src/test/java/com/vaadin/tests/components/grid/GridEditorTabSkipsNonEditableCellsTest.java b/uitest/src/test/java/com/vaadin/tests/components/grid/GridEditorTabSkipsNonEditableCellsTest.java
new file mode 100644
index 0000000000..9092f0a22f
--- /dev/null
+++ b/uitest/src/test/java/com/vaadin/tests/components/grid/GridEditorTabSkipsNonEditableCellsTest.java
@@ -0,0 +1,130 @@
+package com.vaadin.tests.components.grid;
+
+import com.vaadin.testbench.elements.ButtonElement;
+import com.vaadin.testbench.elements.GridElement;
+import com.vaadin.testbench.elements.TextFieldElement;
+import com.vaadin.testbench.parallel.TestCategory;
+import com.vaadin.tests.tb3.MultiBrowserTest;
+import org.junit.Assert;
+import org.junit.Test;
+import org.openqa.selenium.Keys;
+import org.openqa.selenium.WebElement;
+import org.openqa.selenium.interactions.Actions;
+
+import static org.junit.Assert.fail;
+
+/**
+ * Makes sure that pressing Tab when the Grid is in edit mode will make focus
+ * skip cells that are not editable.
+ */
+@TestCategory("grid")
+public class GridEditorTabSkipsNonEditableCellsTest extends MultiBrowserTest {
+    /**
+     * The grid with 5 columns. First, third and fifth columns are not editable.
+     */
+    private GridElement grid;
+
+    @Override
+    public void setup() throws Exception {
+        super.setup();
+        openTestURL();
+        grid = $(GridElement.class).first();
+    }
+
+    @Test
+    public void tabSkipsOverNotEditableFieldBuffered() {
+        setBuffered(true);
+        openEditor(0, 1);
+        pressTab();
+        Assert.assertEquals("col3_0", getFocusedEditorCellContents());
+    }
+
+    @Test
+    public void tabDoesNothingIfAlreadyOnLastEditableFieldBuffered() {
+        setBuffered(true);
+        openEditor(0, 3);
+        pressTab();
+        Assert.assertEquals("col3_0", getFocusedEditorCellContents());
+    }
+
+    @Test
+    public void tabSkipsOverNotEditableFieldUnbuffered() {
+        setBuffered(false);
+        openEditor(0, 1);
+        pressTab();
+        Assert.assertEquals("col3_0", getFocusedEditorCellContents());
+    }
+
+    @Test
+    public void tabMovesToNextRowFirstEditableFieldUnbuffered() {
+        setBuffered(false);
+        openEditor(0, 3);
+        pressTab();
+        Assert.assertEquals("col1_1", getFocusedEditorCellContents());
+    }
+
+    @Test
+    public void shiftTabSkipsOverNotEditableFieldBuffered() {
+        setBuffered(true);
+        openEditor(0, 3);
+        pressShiftTab();
+        Assert.assertEquals("col1_0", getFocusedEditorCellContents());
+    }
+
+    @Test
+    public void shiftTabDoesNothingIfAlreadyOnLastEditableFieldBuffered() {
+        setBuffered(true);
+        openEditor(0, 1);
+        pressShiftTab();
+        Assert.assertEquals("col1_0", getFocusedEditorCellContents());
+    }
+
+    @Test
+    public void shiftTabSkipsOverNotEditableFieldUnbuffered() {
+        setBuffered(false);
+        openEditor(0, 3);
+        pressShiftTab();
+        Assert.assertEquals("col1_0", getFocusedEditorCellContents());
+    }
+
+    @Test
+    public void shiftTabMovesToNextRowFirstEditableFieldUnbuffered() {
+        setBuffered(false);
+        openEditor(1, 1);
+        pressShiftTab();
+        Assert.assertEquals("col3_0", getFocusedEditorCellContents());
+    }
+
+    private void openEditor(int rowIndex, int colIndex) {
+        grid.getCell(rowIndex, colIndex).doubleClick();
+    }
+
+    private void pressTab() {
+        new Actions(getDriver()).sendKeys(Keys.TAB).perform();
+    }
+
+    private void pressShiftTab() {
+        new Actions(getDriver()).keyDown(Keys.SHIFT).sendKeys(Keys.TAB)
+                .keyUp(Keys.SHIFT).perform();
+    }
+
+    private void setBuffered(boolean buffered) {
+        $(ButtonElement.class).caption(buffered ? "Set Editor Buffered Mode On"
+                : "Set Editor Buffered Mode Off").first().click();
+    }
+
+    private String getFocusedEditorCellContents() {
+        final GridElement.GridEditorElement editor = grid.getEditor();
+        final WebElement focusedElement = getFocusedElement();
+        for (int i = 0; i < 5; i++) {
+            if (editor.isEditable(i)
+                    && editor.getField(i).equals(focusedElement)) {
+                return (editor.getField(i).wrap(TextFieldElement.class))
+                        .getValue();
+            }
+        }
+        fail("Currently focused element is not a cell editor: "
+                + focusedElement);
+        return null;
+    }
+}