Merge pull request #1235 from ispyisail/fix/bugtracker-112-editor-snap-zoomed-out

Fix bugtracker #112: no snap in the symbol editor below 100 % zoom

tests/qttest/CMakeLists.txt

@@ -104,6 +104,13 @@ add_test(NAME tst_textgrid COMMAND tst_textgrid)
 target_include_directories(tst_textgrid PRIVATE ${QET_DIR}/sources)
 target_link_libraries(tst_textgrid PRIVATE Qt::Test)
 
+# elementviewgrid.h is header-only: the symbol editor's snap step at each
+# zoom (bugtracker #112), tested without an editor window.
+add_executable(tst_elementviewgrid tst_elementviewgrid.cpp)
+add_test(NAME tst_elementviewgrid COMMAND tst_elementviewgrid)
+target_include_directories(tst_elementviewgrid PRIVATE ${QET_DIR}/sources)
+target_link_libraries(tst_elementviewgrid PRIVATE Qt::Test)
+
 # alignment.h is header-only too (it builds on textgrid.h): the geometry
 # behind the align commands, tested without a scene.
 add_executable(tst_alignment tst_alignment.cpp)

tests/qttest/tst_elementviewgrid.cpp

@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <QtTest>
+
+#include "editor/elementviewgrid.h"
+
+// The symbol editor's snap step at each zoom (bugtracker #112): below
+// 100 % the grid is hidden but parts must still snap every 10 units.
+class tst_elementviewgrid : public QObject
+{
+	Q_OBJECT
+
+private slots:
+	void stepAtZoom_data()
+	{
+		QTest::addColumn<qreal>("zoom");
+		QTest::addColumn<int>("step");
+		QTest::addColumn<bool>("drawGrid");
+		QTest::addColumn<bool>("drawCross");
+
+		QTest::newRow("10 % (fit to a big symbol)") << 0.10 << 10 << false << false;
+		QTest::newRow("62.5 %, the #112 case")      << 0.625 << 10 << false << false;
+		QTest::newRow("100 %")                      << 1.0  << 10 << true  << false;
+		QTest::newRow("200 %")                      << 2.0  << 10 << true  << false;
+		QTest::newRow("400 %")                      << 4.0  << 5  << true  << true;
+		QTest::newRow("800 %")                      << 8.0  << 2  << true  << true;
+		QTest::newRow("1000 %")                     << 10.0 << 1  << true  << true;
+
+		// Just below each threshold: the comparisons are strict (<), so a
+		// change to <= would move these rows into the next band.
+		QTest::newRow("99.9 %")                     << 0.999 << 10 << false << false;
+		QTest::newRow("399.9 %")                    << 3.999 << 10 << true  << false;
+		QTest::newRow("401 %")                      << 4.01  << 5  << true  << true;
+		QTest::newRow("799.9 %")                    << 7.999 << 5  << true  << true;
+		QTest::newRow("999.9 %")                    << 9.999 << 2  << true  << true;
+	}
+
+	void stepAtZoom()
+	{
+		QFETCH(qreal, zoom);
+		QFETCH(int, step);
+		QFETCH(bool, drawGrid);
+		QFETCH(bool, drawCross);
+
+		const ElementViewGrid grid = ElementViewGrid::forZoom(zoom);
+		QCOMPARE(grid.step, step);
+		QCOMPARE(grid.draw_grid, drawGrid);
+		QCOMPARE(grid.draw_cross, drawCross);
+	}
+};
+
+QTEST_APPLESS_MAIN(tst_elementviewgrid)
+
+#include "tst_elementviewgrid.moc"