QTest: rip out qxp::function_ref from reportResult()

This is causing huge code bloat because everything is a local lambda.
Instead, pass direct type-erased function and data pointers to the
replacement function. Testing with tst_qcborvalue, this reduces the
compilation time and the output binary size significantly:

                   Before                   After
Compiler        Time      Size          Time     Size
GCC 13.2        136.99 s  202.3 MB      13.88 s  14.3 MB
GCC 14.0        131.49 s  202.7 MB      14.69 s  14.4 MB
Clang 17        77.2 s    146.7 MB      13.62 s  12.2 MB
Clang 18        141.9 s   187.1 MB      13.62 s  12.4 MB

This causes a difference in how toString() overloads are
found. Previously it would match far more overloads because the
toString() calls were expanded by the macro. Now, we depend on
Argument-Dependent Lookup and associated namespaces, so toString()
overloads should not be in the QTest namespace any more.

With this patch applied, the testlib testcase of tst_selftest
started failing, because nullptr is now handled differently.
However, I consider it as a bugfix, because previously it was
falling back to a default implementation, and now it is using
the QTest::toString(std::nullptr_t) overload, which is a
desired behavior. Update the reference files for tst_selftest
with the new expected output.

Task-number: QTBUG-124272
Change-Id: Ie28eadac333c4bcd8c08fffd17c5484186accdf6
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>

7 files changed, 10 insertions, 14 deletions

diff --git a/tests/auto/testlib/selftests/expected_testlib.junitxml b/tests/auto/testlib/selftests/expected_testlib.junitxml
index f5d3a94126..33c8bfe403 100644
--- a/tests/auto/testlib/selftests/expected_testlib.junitxml
+++ b/tests/auto/testlib/selftests/expected_testlib.junitxml
@@ -9,7 +9,7 @@
   <testcase name="basics" classname="tst_TestLib" time="@TEST_DURATION@">
     <failure type="fail" message="Compared QObject pointers are not the same">
       <![CDATA[   Actual   (QTest::testObject()): tst_TestLib/"TestObject"
-   Expected (nullptr)            : (nullptr)]]>
+   Expected (nullptr)            : "nullptr"]]>
     </failure>
   </testcase>
   <testcase name="delays" classname="tst_TestLib" time="@TEST_DURATION@"/>
diff --git a/tests/auto/testlib/selftests/expected_testlib.lightxml b/tests/auto/testlib/selftests/expected_testlib.lightxml
index cd0f96d6d4..76435eb9f0 100644
--- a/tests/auto/testlib/selftests/expected_testlib.lightxml
+++ b/tests/auto/testlib/selftests/expected_testlib.lightxml
@@ -11,7 +11,7 @@
     <Incident type="fail" file="qtbase/tests/auto/testlib/selftests/testlib/tst_testlib.cpp" line="0">
       <Description><![CDATA[Compared QObject pointers are not the same
    Actual   (QTest::testObject()): tst_TestLib/"TestObject"
-   Expected (nullptr)            : (nullptr)]]></Description>
+   Expected (nullptr)            : "nullptr"]]></Description>
     </Incident>
     <Duration msecs="0"/>
   </TestFunction>
diff --git a/tests/auto/testlib/selftests/expected_testlib.tap b/tests/auto/testlib/selftests/expected_testlib.tap
index 4a6056bc77..1fa7dc77c4 100644
--- a/tests/auto/testlib/selftests/expected_testlib.tap
+++ b/tests/auto/testlib/selftests/expected_testlib.tap
@@ -5,9 +5,9 @@ not ok 2 - basics()
   ---
   type: QCOMPARE
   message: Compared QObject pointers are not the same
-  wanted: (nullptr) (nullptr)
+  wanted: "nullptr" (nullptr)
   found: tst_TestLib/"TestObject" (QTest::testObject())
-  expected: (nullptr) (nullptr)
+  expected: "nullptr" (nullptr)
   actual: tst_TestLib/"TestObject" (QTest::testObject())
   at: tst_TestLib::basics() (qtbase/tests/auto/testlib/selftests/testlib/tst_testlib.cpp:0)
   file: qtbase/tests/auto/testlib/selftests/testlib/tst_testlib.cpp
diff --git a/tests/auto/testlib/selftests/expected_testlib.teamcity b/tests/auto/testlib/selftests/expected_testlib.teamcity
index 279ef03f3f..52f7fa244c 100644
--- a/tests/auto/testlib/selftests/expected_testlib.teamcity
+++ b/tests/auto/testlib/selftests/expected_testlib.teamcity
@@ -2,7 +2,7 @@
 ##teamcity[testStarted name='initTestCase()' flowId='tst_TestLib']
 ##teamcity[testFinished name='initTestCase()' flowId='tst_TestLib']
 ##teamcity[testStarted name='basics()' flowId='tst_TestLib']
-##teamcity[testFailed name='basics()' message='Failure! |[Loc: qtbase/tests/auto/testlib/selftests/testlib/tst_testlib.cpp(0)|]' details='Compared QObject pointers are not the same|n Actual (QTest::testObject()): tst_TestLib/"TestObject"|n Expected (nullptr) : (nullptr)' flowId='tst_TestLib']
+##teamcity[testFailed name='basics()' message='Failure! |[Loc: qtbase/tests/auto/testlib/selftests/testlib/tst_testlib.cpp(0)|]' details='Compared QObject pointers are not the same|n Actual (QTest::testObject()): tst_TestLib/"TestObject"|n Expected (nullptr) : "nullptr"' flowId='tst_TestLib']
 ##teamcity[testFinished name='basics()' flowId='tst_TestLib']
 ##teamcity[testStarted name='delays()' flowId='tst_TestLib']
 ##teamcity[testFinished name='delays()' flowId='tst_TestLib']
diff --git a/tests/auto/testlib/selftests/expected_testlib.txt b/tests/auto/testlib/selftests/expected_testlib.txt
index a0b8a275d0..4d652626e9 100644
--- a/tests/auto/testlib/selftests/expected_testlib.txt
+++ b/tests/auto/testlib/selftests/expected_testlib.txt
@@ -3,7 +3,7 @@ Config: Using QtTest library
 PASS   : tst_TestLib::initTestCase()
 FAIL!  : tst_TestLib::basics() Compared QObject pointers are not the same
    Actual   (QTest::testObject()): tst_TestLib/"TestObject"
-   Expected (nullptr)            : (nullptr)
+   Expected (nullptr)            : "nullptr"
    Loc: [qtbase/tests/auto/testlib/selftests/testlib/tst_testlib.cpp(0)]
 PASS   : tst_TestLib::delays()
 PASS   : tst_TestLib::reals(zero)
diff --git a/tests/auto/testlib/selftests/expected_testlib.xml b/tests/auto/testlib/selftests/expected_testlib.xml
index 241fd3f8d1..8b66b003d0 100644
--- a/tests/auto/testlib/selftests/expected_testlib.xml
+++ b/tests/auto/testlib/selftests/expected_testlib.xml
@@ -13,7 +13,7 @@
     <Incident type="fail" file="qtbase/tests/auto/testlib/selftests/testlib/tst_testlib.cpp" line="0">
       <Description><![CDATA[Compared QObject pointers are not the same
    Actual   (QTest::testObject()): tst_TestLib/"TestObject"
-   Expected (nullptr)            : (nullptr)]]></Description>
+   Expected (nullptr)            : "nullptr"]]></Description>
     </Incident>
     <Duration msecs="0"/>
   </TestFunction>
diff --git a/tests/auto/testlib/selftests/extendedcompare/tst_extendedcompare.cpp b/tests/auto/testlib/selftests/extendedcompare/tst_extendedcompare.cpp
index cc75e7f7fb..70a7798667 100644
--- a/tests/auto/testlib/selftests/extendedcompare/tst_extendedcompare.cpp
+++ b/tests/auto/testlib/selftests/extendedcompare/tst_extendedcompare.cpp
@@ -93,11 +93,13 @@ static ClassWithPointerGetter getClassForValue(int val)
 // various toString() overloads
 namespace QTest {
 
-char *toString(const int *val)
+template <> char *toString(const int *const &val)
 {
     return val ? toString(*val) : toString(nullptr);
 }
 
+} // namespace QTest
+
 char *toString(const MyClass &val)
 {
     char *msg = new char[128];
@@ -117,8 +119,6 @@ char *toString(const MyClass *val)
     return toString(nullptr);
 }
 
-} // namespace QTest
-
 enum MyUnregisteredEnum { MyUnregisteredEnumValue1, MyUnregisteredEnumValue2 };
 
 class tst_ExtendedCompare : public QObject
@@ -293,8 +293,6 @@ public:
     }
 };
 
-namespace QTest {
-
 char *toString(const ClassWithDeferredSetter &val)
 {
     char *msg = new char[128];
@@ -302,8 +300,6 @@ char *toString(const ClassWithDeferredSetter &val)
     return msg;
 }
 
-} // namespace QTest
-
 void tst_ExtendedCompare::checkComparisonWithTimeout()
 {
     QFETCH_GLOBAL(QTest::ComparisonOperation, operation);