Long live QSize(F)::grownBy/shrunkBy()

These functions tighten the integration of QMargins(F) with the rest
of the geometry classes by providing a way to apply margins to sizes
(and later, rects).

Apply them in a few obvious cases across QtWidgets.

[ChangeLog][QtCore][QSize/QSizeF] Added grownBy(QMargin(F))/shrunkBy(QMargin(F)).

Change-Id: I8a549436824cdb7fb6125a8cde89d5bf02826934
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

2 files changed, 88 insertions, 0 deletions

diff --git a/tests/auto/corelib/tools/qsize/tst_qsize.cpp b/tests/auto/corelib/tools/qsize/tst_qsize.cpp
index 385ff18ce5..6824bad9c8 100644
--- a/tests/auto/corelib/tools/qsize/tst_qsize.cpp
+++ b/tests/auto/corelib/tools/qsize/tst_qsize.cpp
@@ -29,6 +29,7 @@
 #include <QtTest/QtTest>
 #include <qsize.h>
 
+Q_DECLARE_METATYPE(QMargins)
 
 class tst_QSize : public QObject
 {
@@ -43,6 +44,9 @@ private slots:
     void boundedTo_data();
     void boundedTo();
 
+    void grownOrShrunkBy_data();
+    void grownOrShrunkBy();
+
     void transpose_data();
     void transpose();
 };
@@ -186,6 +190,46 @@ void tst_QSize::boundedTo()
     QCOMPARE( input1.boundedTo(input2), expected);
 }
 
+void tst_QSize::grownOrShrunkBy_data()
+{
+    QTest::addColumn<QSize>("input");
+    QTest::addColumn<QMargins>("margins");
+    QTest::addColumn<QSize>("grown");
+    QTest::addColumn<QSize>("shrunk");
+
+    auto row = [](QSize i, QMargins m, QSize g, QSize s) {
+        QTest::addRow("{%d,%d}/{%d,%d,%d,%d}", i.width(), i.height(),
+                      m.left(), m.top(), m.right(), m.bottom())
+                << i << m << g << s;
+    };
+
+    const QSize zero = {0, 0};
+    const QSize some = {100, 200};
+    const QMargins zeroMargins = {};
+    const QMargins negative = {-1, -2, -3, -4};
+    const QMargins positive = { 1,  2,  3,  4};
+
+    row(zero, zeroMargins, zero, zero);
+    row(zero, negative, {-4, -6}, { 4,  6});
+    row(zero, positive, { 4,  6}, {-4, -6});
+    row(some, zeroMargins, some, some);
+    row(some, negative, { 96, 194}, {104, 206});
+    row(some, positive, {104, 206}, { 96, 194});
+}
+
+void tst_QSize::grownOrShrunkBy()
+{
+    QFETCH(const QSize, input);
+    QFETCH(const QMargins, margins);
+    QFETCH(const QSize, grown);
+    QFETCH(const QSize, shrunk);
+
+    QCOMPARE(input.grownBy(margins), grown);
+    QCOMPARE(input.shrunkBy(margins), shrunk);
+    QCOMPARE(grown.shrunkBy(margins), input);
+    QCOMPARE(shrunk.grownBy(margins), input);
+}
+
 void tst_QSize::transpose_data()
 {
     QTest::addColumn<QSize>("input1");
diff --git a/tests/auto/corelib/tools/qsizef/tst_qsizef.cpp b/tests/auto/corelib/tools/qsizef/tst_qsizef.cpp
index 42801d63a9..bbffa74a62 100644
--- a/tests/auto/corelib/tools/qsizef/tst_qsizef.cpp
+++ b/tests/auto/corelib/tools/qsizef/tst_qsizef.cpp
@@ -29,6 +29,7 @@
 #include <QtTest/QtTest>
 #include <qsize.h>
 
+Q_DECLARE_METATYPE(QMarginsF)
 
 class tst_QSizeF : public QObject
 {
@@ -45,6 +46,9 @@ private slots:
     void boundedTo_data();
     void boundedTo();
 
+    void grownOrShrunkBy_data();
+    void grownOrShrunkBy();
+
     void transpose_data();
     void transpose();
 };
@@ -152,6 +156,46 @@ void tst_QSizeF::boundedTo() {
     QCOMPARE( input1.boundedTo(input2), expected);
 }
 
+void tst_QSizeF::grownOrShrunkBy_data()
+{
+    QTest::addColumn<QSizeF>("input");
+    QTest::addColumn<QMarginsF>("margins");
+    QTest::addColumn<QSizeF>("grown");
+    QTest::addColumn<QSizeF>("shrunk");
+
+    auto row = [](QSizeF i, QMarginsF m, QSizeF g, QSizeF s) {
+        QTest::addRow("{%g,%g}/{%g,%g,%g,%g}", i.width(), i.height(),
+                      m.left(), m.top(), m.right(), m.bottom())
+                << i << m << g << s;
+    };
+
+    const QSizeF zero = {0, 0};
+    const QSizeF some = {100, 200};
+    const QMarginsF zeroMargins = {};
+    const QMarginsF negative = {-1, -2, -3, -4};
+    const QMarginsF positive = { 1,  2,  3,  4};
+
+    row(zero, zeroMargins, zero, zero);
+    row(zero, negative, {-4, -6}, { 4,  6});
+    row(zero, positive, { 4,  6}, {-4, -6});
+    row(some, zeroMargins, some, some);
+    row(some, negative, { 96, 194}, {104, 206});
+    row(some, positive, {104, 206}, { 96, 194});
+}
+
+void tst_QSizeF::grownOrShrunkBy()
+{
+    QFETCH(const QSizeF, input);
+    QFETCH(const QMarginsF, margins);
+    QFETCH(const QSizeF, grown);
+    QFETCH(const QSizeF, shrunk);
+
+    QCOMPARE(input.grownBy(margins), grown);
+    QCOMPARE(input.shrunkBy(margins), shrunk);
+    QCOMPARE(grown.shrunkBy(margins), input);
+    QCOMPARE(shrunk.grownBy(margins), input);
+}
+
 void tst_QSizeF::transpose_data() {
     QTest::addColumn<QSizeF>("input1");
     QTest::addColumn<QSizeF>("expected");