QFileInfo: Use new comparison helper macros

QFileInfo had operator==() and operator!=() defined as public member
functions, so use QT_CORE_REMOVED_SINCE and removed_api.cpp to get
rid of these methods and replace them with a hidden friend.

Use QT_TEST_ALL_EQUALITY_OPS macro in unit-tests.

Task-number: QTBUG-120303
Change-Id: Ie290df230b0f608a0965dccba9184382291cad8e
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>

src/corelib/compat/removed_api.cpp

@@ -926,6 +926,13 @@ bool QDir::operator==(const QDir &dir) const
     return comparesEqual(*this, dir);
 }
 
+#include "qfileinfo.h" // inlined API
+
+bool QFileInfo::operator==(const QFileInfo &fileinfo) const
+{
+    return comparesEqual(*this, fileinfo);
+}
+
 // #include "qotherheader.h"
 // // implement removed functions from qotherheader.h
 // order sections alphabetically to reduce chances of merge conflicts

src/corelib/io/qfileinfo.cpp

@@ -419,16 +419,18 @@ QFileInfo::~QFileInfo()
 }
 
 /*!
-    \fn bool QFileInfo::operator!=(const QFileInfo &fileinfo) const
+    \fn bool QFileInfo::operator!=(const QFileInfo &lhs, const QFileInfo &rhs)
 
-    Returns \c true if this QFileInfo refers to a different file system
+    Returns \c true if QFileInfo \a lhs refers to a different file system
-    entry than the one referred to by \a fileinfo; otherwise returns \c false.
+    entry than the one referred to by \a rhs; otherwise returns \c false.
 
     \sa operator==()
 */
 
 /*!
-    Returns \c true if this QFileInfo and \a fileinfo refer to the same
+    \fn bool QFileInfo::operator==(const QFileInfo &lhs, const QFileInfo &rhs)
+
+    Returns \c true if QFileInfo \a lhs and QFileInfo \a rhs refer to the same
     entry on the file system; otherwise returns \c false.
 
     Note that the result of comparing two empty QFileInfo objects, containing
@@ -443,34 +445,31 @@ QFileInfo::~QFileInfo()
 
     \sa operator!=()
 */
-bool QFileInfo::operator==(const QFileInfo &fileinfo) const
+bool comparesEqual(const QFileInfo &lhs, const QFileInfo &rhs)
 {
-    Q_D(const QFileInfo);
+    if (rhs.d_ptr == lhs.d_ptr)
-    // ### Qt 5: understand long and short file names on Windows
-    // ### (GetFullPathName()).
-    if (fileinfo.d_ptr == d_ptr)
         return true;
-    if (d->isDefaultConstructed || fileinfo.d_ptr->isDefaultConstructed)
+    if (lhs.d_ptr->isDefaultConstructed || rhs.d_ptr->isDefaultConstructed)
         return false;
 
     // Assume files are the same if path is the same
-    if (d->fileEntry.filePath() == fileinfo.d_ptr->fileEntry.filePath())
+    if (lhs.d_ptr->fileEntry.filePath() == rhs.d_ptr->fileEntry.filePath())
         return true;
 
     Qt::CaseSensitivity sensitive;
-    if (d->fileEngine == nullptr || fileinfo.d_ptr->fileEngine == nullptr) {
+    if (lhs.d_ptr->fileEngine == nullptr || rhs.d_ptr->fileEngine == nullptr) {
-        if (d->fileEngine != fileinfo.d_ptr->fileEngine) // one is native, the other is a custom file-engine
+        if (lhs.d_ptr->fileEngine != rhs.d_ptr->fileEngine) // one is native, the other is a custom file-engine
             return false;
 
         sensitive = QFileSystemEngine::isCaseSensitive() ? Qt::CaseSensitive : Qt::CaseInsensitive;
     } else {
-        if (d->fileEngine->caseSensitive() != fileinfo.d_ptr->fileEngine->caseSensitive())
+        if (lhs.d_ptr->fileEngine->caseSensitive() != rhs.d_ptr->fileEngine->caseSensitive())
             return false;
-        sensitive = d->fileEngine->caseSensitive() ? Qt::CaseSensitive : Qt::CaseInsensitive;
+        sensitive = lhs.d_ptr->fileEngine->caseSensitive() ? Qt::CaseSensitive : Qt::CaseInsensitive;
     }
 
    // Fallback to expensive canonical path computation
-   return canonicalFilePath().compare(fileinfo.canonicalFilePath(), sensitive) == 0;
+   return lhs.canonicalFilePath().compare(rhs.canonicalFilePath(), sensitive) == 0;
 }
 
 /*!

src/corelib/io/qfileinfo.h

@@ -4,6 +4,7 @@
 #ifndef QFILEINFO_H
 #define QFILEINFO_H
 
+#include <QtCore/qcompare.h>
 #include <QtCore/qfile.h>
 #include <QtCore/qlist.h>
 #include <QtCore/qshareddata.h>
@@ -58,8 +59,10 @@ public:
     void swap(QFileInfo &other) noexcept
     { d_ptr.swap(other.d_ptr); }
 
+#if QT_CORE_REMOVED_SINCE(6, 8)
     bool operator==(const QFileInfo &fileinfo) const;
     inline bool operator!=(const QFileInfo &fileinfo) const { return !(operator==(fileinfo)); }
+#endif
 
     void setFile(const QString &file);
     void setFile(const QFileDevice &file);
@@ -171,6 +174,8 @@ protected:
     QSharedDataPointer<QFileInfoPrivate> d_ptr;
 
 private:
+    friend Q_CORE_EXPORT bool comparesEqual(const QFileInfo &lhs, const QFileInfo &rhs);
+    Q_DECLARE_EQUALITY_COMPARABLE(QFileInfo)
     QFileInfoPrivate* d_func();
     inline const QFileInfoPrivate* d_func() const
     {

tests/auto/corelib/io/qfileinfo/CMakeLists.txt

@@ -16,6 +16,7 @@ qt_internal_add_test(tst_qfileinfo
         tst_qfileinfo.cpp
     LIBRARIES
         Qt::CorePrivate
+        Qt::TestPrivate
 )
 
 # Resources:

tests/auto/corelib/io/qfileinfo/tst_qfileinfo.cpp

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
 
 #include <QTest>
+#include <QtTest/private/qcomparisontesthelper_p.h>
 #include <QStandardPaths>
 #include <QScopeGuard>
 
@@ -172,6 +173,7 @@ private slots:
 
     void systemFiles();
 
+    void compareCompiles();
     void compare_data();
     void compare();
 
@@ -993,6 +995,11 @@ void tst_QFileInfo::systemFiles()
     QVERIFY(fi.birthTime() <= fi.lastModified());
 }
 
+void tst_QFileInfo::compareCompiles()
+{
+    QTestPrivate::testEqualityOperatorsCompile<QFileInfo>();
+}
+
 void tst_QFileInfo::compare_data()
 {
     QTest::addColumn<QString>("file1");
@@ -1037,7 +1044,7 @@ void tst_QFileInfo::compare()
     QFETCH(QString, file2);
     QFETCH(bool, same);
     QFileInfo fi1(file1), fi2(file2);
-    QCOMPARE(fi1 == fi2, same);
+    QT_TEST_EQUALITY_OPS(fi1, fi2, same);
 }
 
 void tst_QFileInfo::consistent_data()