tst_QStringApiSymmetry: avoid repetition in trimmed_data()

Enclosing one string in each substring of another does not need to
repeat the empty substring of the latter. Extracting the empty
substring from different positions doesn't get different results.
In the process, tidy up the code a bit.

Change-Id: Ic66febbdadeaac0c466f4f1174d831a991d31e20
Reviewed-by: Marc Mutz <marc.mutz@qt.io>

1 files changed, 10 insertions, 8 deletions

diff --git a/tests/auto/corelib/text/qstringapisymmetry/tst_qstringapisymmetry.cpp b/tests/auto/corelib/text/qstringapisymmetry/tst_qstringapisymmetry.cpp
index 4c8e45f17e..235a1493dc 100644
--- a/tests/auto/corelib/text/qstringapisymmetry/tst_qstringapisymmetry.cpp
+++ b/tests/auto/corelib/text/qstringapisymmetry/tst_qstringapisymmetry.cpp
@@ -2466,18 +2466,20 @@ void tst_QStringApiSymmetry::trimmed_data()
     QTest::addColumn<QString>("unicode");
     QTest::addColumn<QAnyStringView>("result");
 
-    const auto latin1Whitespace = QLatin1String(" \r\n\t\f\v");
+    const auto latin1Whitespace = QLatin1StringView(" \r\n\t\f\v");
 
     QTest::addRow("null") << QString() << QAnyStringView();
 
     auto add = [latin1Whitespace](const QString &str) {
-        // run through all substrings of latin1Whitespace
-        for (int len = 0; len < latin1Whitespace.size(); ++len) {
-            for (int pos = 0; pos < latin1Whitespace.size() - len; ++pos) {
-                const QString unicode = latin1Whitespace.mid(pos, len) + str + latin1Whitespace.mid(pos, len);
-                const QScopedArrayPointer<const char> escaped(QTest::toString(unicode));
-                QTest::addRow("%s", escaped.data()) << unicode << QAnyStringView(str);
-            }
+        auto row = [&](QLatin1StringView spaces) {
+            const QString unicode = spaces + str + spaces;
+            const QScopedArrayPointer<const char> escaped(QTest::toString(unicode));
+            QTest::addRow("%s", escaped.data()) << unicode << QAnyStringView(str);
+        };
+        row({}); // The len = 0 case of the following.
+        for (qsizetype len = 1; len < latin1Whitespace.size(); ++len) {
+            for (qsizetype pos = 0; pos < latin1Whitespace.size() - len; ++pos)
+                row (latin1Whitespace.mid(pos, len));
         }
     };