From 4467ebc837aded07b0b0cbc3b34ce67f2c0e96f3 Mon Sep 17 00:00:00 2001
From: Edward Welbourne <edward.welbourne@qt.io>
Date: Wed, 17 Apr 2024 16:30:24 +0200
Subject: [PATCH] Add benchmarks for QDate::fromString()

These reveal a roughly factor of six slow-down for two valid date
formats and a roughly factor of twelve slow-down for an invalid one.

Pick-to: 6.7 6.5 6.2
Task-number: QTBUG-124465
Change-Id: Ibd21e43d4c64aced33ba5b21e4602e0dc4fd7548
Reviewed-by: Mate Barany <mate.barany@qt.io>
---
 .../corelib/time/qdate/tst_bench_qdate.cpp    | 27 +++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/tests/benchmarks/corelib/time/qdate/tst_bench_qdate.cpp b/tests/benchmarks/corelib/time/qdate/tst_bench_qdate.cpp
index 581c300d364..7dde3bf4265 100644
--- a/tests/benchmarks/corelib/time/qdate/tst_bench_qdate.cpp
+++ b/tests/benchmarks/corelib/time/qdate/tst_bench_qdate.cpp
@@ -4,6 +4,7 @@
 #include <QDate>
 #include <QTest>
 #include <QList>
+using namespace Qt::StringLiterals;
 
 class tst_QDate : public QObject
 {
@@ -33,6 +34,9 @@ private Q_SLOTS:
     void addDays();
     void addMonths();
     void addYears();
+
+    void fromString_data();
+    void fromString();
 };
 
 QList<QDate> tst_QDate::daily(qint64 start, qint64 end)
@@ -184,5 +188,28 @@ void tst_QDate::addYears()
     Q_UNUSED(store);
 }
 
+void tst_QDate::fromString_data()
+{
+    QTest::addColumn<QString>("string");
+    QTest::addColumn<QString>("format");
+    QTest::addColumn<int>("baseYear");
+
+    QTest::newRow("yyyyMMdd") << u"20240412"_s << u"yyyyMMdd"_s << 2000;
+    QTest::newRow("yyyy-MM-dd") << u"2024-04-12"_s << u"yyyy-MM-dd"_s << 2000;
+    QTest::newRow("YYYYMMDD") << u"20240412"_s << u"YYYYMMDD"_s << 2000; // Invalid, QTBUG-124465.
+}
+
+void tst_QDate::fromString()
+{
+    QFETCH(const QString, string);
+    QFETCH(const QString, format);
+    QFETCH(const int, baseYear);
+    QDate date;
+    QBENCHMARK {
+        date = QDate::fromString(string, format, baseYear);
+    }
+    Q_UNUSED(date);
+}
+
 QTEST_MAIN(tst_QDate)
 #include "tst_bench_qdate.moc"