Make it explicit that TableView's rowHeight and columnWidthProvider's can also return undefined

Change-Id: I074c817a9e29a385ba2b6b8ee32c06c84853ac99
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>
(cherry picked from commit 090865a11230f42069b1c5c0ef8ac251183f6f74)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
(cherry picked from commit af1742c0af05b619056bd347e7ec63a71b2a067c)

3 files changed, 46 insertions, 6 deletions

diff --git a/src/quick/items/qquicktableview.cpp b/src/quick/items/qquicktableview.cpp
index ea02fcb51d..31d2aff4d1 100644
--- a/src/quick/items/qquicktableview.cpp
+++ b/src/quick/items/qquicktableview.cpp
@@ -180,8 +180,8 @@
     Since Qt 5.13, if you want to hide a specific column, you can return \c 0
     from the \l columnWidthProvider for that column. Likewise, you can return 0
     from the \l rowHeightProvider to hide a row. If you return a negative
-    number, TableView will fall back to calculate the size based on the delegate
-    items.
+    number or \c undefined, TableView will fall back to calculate the size based
+    on the delegate items.
 
     \note The size of a row or column should be a whole number to avoid
     sub-pixel alignment of items.
@@ -454,8 +454,8 @@
     for which the TableView needs to know the width.
 
     Since Qt 5.13, if you want to hide a specific column, you can return \c 0
-    width for that column. If you return a negative number, TableView
-    calculates the width based on the delegate items.
+    width for that column. If you return a negative number or \c undefined,
+    TableView calculates the width based on the delegate items.
 
     \note The columnWidthProvider will usually be called two times when
     a column is about to load (or when doing layout). First, to know if
diff --git a/tests/auto/quick/qquicktableview/data/userowcolumnprovider.qml b/tests/auto/quick/qquicktableview/data/userowcolumnprovider.qml
index 686bed12d0..e812288507 100644
--- a/tests/auto/quick/qquicktableview/data/userowcolumnprovider.qml
+++ b/tests/auto/quick/qquicktableview/data/userowcolumnprovider.qml
@@ -10,6 +10,8 @@ Item {
 
     property alias tableView: tableView
     property Component delegate: tableViewDelegate
+    property bool returnUndefinedColumnWidth: false
+    property bool returnUndefinedRowHeight: false
     property bool returnNegativeColumnWidth: false
     property bool returnNegativeRowHeight: false
 
@@ -25,12 +27,14 @@ Item {
         columnWidthProvider: function(column) {
             if (returnNegativeColumnWidth)
                 return -1
-            return column + 10
+            if (!returnUndefinedColumnWidth)
+                return column + 10
         }
         rowHeightProvider: function(row) {
             if (returnNegativeRowHeight)
                 return -1
-            return row + 10
+            if (!returnUndefinedRowHeight)
+                return row + 10
         }
     }
 
diff --git a/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp b/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp
index 57188f1a86..d450aa018c 100644
--- a/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp
+++ b/tests/auto/quick/qquicktableview/tst_qquicktableview.cpp
@@ -106,11 +106,13 @@ private slots:
     void checkColumnWidthProviderInvalidReturnValues();
     void checkColumnWidthProviderNegativeReturnValue();
     void checkColumnWidthProviderNotCallable();
+    void checkColumnWidthProviderUndefinedReturnValue();
     void checkColumnWidthBoundToViewWidth();
     void checkRowHeightWithoutProvider();
     void checkRowHeightProvider();
     void checkRowHeightProviderInvalidReturnValues();
     void checkRowHeightProviderNegativeReturnValue();
+    void checkRowHeightProviderUndefinedReturnValue();
     void checkRowHeightProviderNotCallable();
     void isColumnLoadedAndIsRowLoaded();
     void checkForceLayoutFunction();
@@ -641,6 +643,23 @@ void tst_QQuickTableView::checkColumnWidthProviderNegativeReturnValue()
         QCOMPARE(fxItem->item->width(), 20);
 }
 
+void tst_QQuickTableView::checkColumnWidthProviderUndefinedReturnValue()
+{
+    // Check that we fall back to use the implicit width of the delegate
+    // items if the columnWidthProvider returns an undefined.
+    LOAD_TABLEVIEW("userowcolumnprovider.qml");
+
+    auto model = TestModelAsVariant(10, 10);
+    view->rootObject()->setProperty("returnUndefinedColumnWidth", true);
+
+    tableView->setModel(model);
+
+    WAIT_UNTIL_POLISHED;
+
+    for (auto fxItem : tableViewPrivate->loadedItems)
+        QCOMPARE(fxItem->item->width(), 20);
+}
+
 void tst_QQuickTableView::checkColumnWidthProviderNotCallable()
 {
     // Check that we fall back to use default columns widths, if you
@@ -759,6 +778,23 @@ void tst_QQuickTableView::checkRowHeightProviderNegativeReturnValue()
         QCOMPARE(fxItem->item->height(), 20);
 }
 
+void tst_QQuickTableView::checkRowHeightProviderUndefinedReturnValue()
+{
+    // Check that we fall back to use the implicit height of the delegate
+    // items if the rowHeightProvider return a negative number.
+    LOAD_TABLEVIEW("userowcolumnprovider.qml");
+
+    auto model = TestModelAsVariant(10, 10);
+    view->rootObject()->setProperty("returnUndefinedRowHeight", true);
+
+    tableView->setModel(model);
+
+    WAIT_UNTIL_POLISHED;
+
+    for (auto fxItem : tableViewPrivate->loadedItems)
+        QCOMPARE(fxItem->item->height(), 20);
+}
+
 void tst_QQuickTableView::checkRowHeightProviderNotCallable()
 {
     // Check that we fall back to use default row heights, if you