From 8e98a161e993c6636d217276a0f2373d642ff050 Mon Sep 17 00:00:00 2001 From: Giuseppe D'Angelo Date: Sat, 15 Feb 2020 00:11:22 +0100 Subject: Long live std::pair! Make QPair an alias for std::pair, and qMakePair just a forwarder towards std::make_pair. Why? Fundamentally to ditch a bunch of NIH code; gain for free structured bindings, std::tuple and std::reference_wrapper compatibility, and so on. Breakages: * Some that code manually forward declares QPair. We don't care about it ( is the proper way). * Some code that overloads on std::pair and QPair. Luckily it's mostly centralized: debug, metatypes, testing macros. Just remove the QPair overload. * Usages of qMakePair forcing the template type parameters. There are a handful of these in qtbase, but only one was actually broken. * std::pair is NOT (and will never likely be) trivially copiable. This is agreed to be a mistake done by practically all implementations in C++11, can can't be fixed without breaking ABI. Some code using QPair assuming it's trivially copiable may break; exactly one occurrence was in qtbase. * QMetaType logic extracts the type names in two different ways, one by looking at the source code string (e.g. extracted by moc) and one via some ad-hoc reflection in C++. We need to make "QPair" (as spelled in the source code) be the same as "std::pair" (gathered via reflection, which will see through the alias) when compared. The way it's already done e.g. for QList is by actually replacing the moc-extracted name with the name of the actual type used in C++; do the same here. On libc++, std::pair is actually in an inline namespace -- i.e. std::__1::pair; the reflection will extract and store "std::__1::pair" so we need an ad-hoc fix to QMetaType. [ChangeLog][QtCore][QPair] QPair is now an alias to std::pair, and does not exist as a class in Qt any more. This may break code such as functions overloaded for both QPair and std::pair. Usually, the overload taking a QPair can be safely discarded, leaving only the one taking a std::pair. QPair API has not changed, and qMakePair is still available for compatibility (although new code is encouraged to use std::pair and std::make_pair directly instead). Change-Id: I7725c751bf23946cde577b1406e86a336c0a3dcf Reviewed-by: Lars Knoll --- tests/auto/testlib/selftests/expected_pairdiagnostics.junitxml | 4 ++-- tests/auto/testlib/selftests/expected_pairdiagnostics.lightxml | 4 ++-- tests/auto/testlib/selftests/expected_pairdiagnostics.tap | 8 ++++---- tests/auto/testlib/selftests/expected_pairdiagnostics.teamcity | 2 +- tests/auto/testlib/selftests/expected_pairdiagnostics.txt | 4 ++-- tests/auto/testlib/selftests/expected_pairdiagnostics.xml | 4 ++-- 6 files changed, 13 insertions(+), 13 deletions(-) (limited to 'tests/auto/testlib') diff --git a/tests/auto/testlib/selftests/expected_pairdiagnostics.junitxml b/tests/auto/testlib/selftests/expected_pairdiagnostics.junitxml index cf2a30b84a..653dde11c0 100644 --- a/tests/auto/testlib/selftests/expected_pairdiagnostics.junitxml +++ b/tests/auto/testlib/selftests/expected_pairdiagnostics.junitxml @@ -8,8 +8,8 @@ + Actual (pair1): "std::pair(1,1)" + Expected (pair2): "std::pair(1,2)"" result="fail"/> + Actual (pair1): "std::pair(1,1)" + Expected (pair2): "std::pair(1,2)"]]> diff --git a/tests/auto/testlib/selftests/expected_pairdiagnostics.tap b/tests/auto/testlib/selftests/expected_pairdiagnostics.tap index 9c45880c2d..d6e1a0b22f 100644 --- a/tests/auto/testlib/selftests/expected_pairdiagnostics.tap +++ b/tests/auto/testlib/selftests/expected_pairdiagnostics.tap @@ -5,10 +5,10 @@ not ok 2 - testQPair() --- type: QCOMPARE message: Compared values are not the same - wanted: "QPair(1,2)" (pair2) - found: "QPair(1,1)" (pair1) - expected: "QPair(1,2)" (pair2) - actual: "QPair(1,1)" (pair1) + wanted: "std::pair(1,2)" (pair2) + found: "std::pair(1,1)" (pair1) + expected: "std::pair(1,2)" (pair2) + actual: "std::pair(1,1)" (pair1) at: tst_PairDiagnostics::testQPair() (qtbase/tests/auto/testlib/selftests/pairdiagnostics/tst_pairdiagnostics.cpp:51) file: qtbase/tests/auto/testlib/selftests/pairdiagnostics/tst_pairdiagnostics.cpp line: 51 diff --git a/tests/auto/testlib/selftests/expected_pairdiagnostics.teamcity b/tests/auto/testlib/selftests/expected_pairdiagnostics.teamcity index 9068e2c45b..a86f4fa254 100644 --- a/tests/auto/testlib/selftests/expected_pairdiagnostics.teamcity +++ b/tests/auto/testlib/selftests/expected_pairdiagnostics.teamcity @@ -2,7 +2,7 @@ ##teamcity[testStarted name='initTestCase()' flowId='tst_PairDiagnostics'] ##teamcity[testFinished name='initTestCase()' flowId='tst_PairDiagnostics'] ##teamcity[testStarted name='testQPair()' flowId='tst_PairDiagnostics'] -##teamcity[testFailed name='testQPair()' message='Failure! |[Loc: qtbase/tests/auto/testlib/selftests/pairdiagnostics/tst_pairdiagnostics.cpp(0)|]' details='Compared values are not the same|n Actual (pair1): "QPair(1,1)"|n Expected (pair2): "QPair(1,2)"' flowId='tst_PairDiagnostics'] +##teamcity[testFailed name='testQPair()' message='Failure! |[Loc: qtbase/tests/auto/testlib/selftests/pairdiagnostics/tst_pairdiagnostics.cpp(0)|]' details='Compared values are not the same|n Actual (pair1): "std::pair(1,1)"|n Expected (pair2): "std::pair(1,2)"' flowId='tst_PairDiagnostics'] ##teamcity[testFinished name='testQPair()' flowId='tst_PairDiagnostics'] ##teamcity[testStarted name='testStdPair()' flowId='tst_PairDiagnostics'] ##teamcity[testFailed name='testStdPair()' message='Failure! |[Loc: qtbase/tests/auto/testlib/selftests/pairdiagnostics/tst_pairdiagnostics.cpp(0)|]' details='Compared values are not the same|n Actual (pair1): "std::pair(1,1)"|n Expected (pair2): "std::pair(1,2)"' flowId='tst_PairDiagnostics'] diff --git a/tests/auto/testlib/selftests/expected_pairdiagnostics.txt b/tests/auto/testlib/selftests/expected_pairdiagnostics.txt index 5e29888ba6..cbb8b764ff 100644 --- a/tests/auto/testlib/selftests/expected_pairdiagnostics.txt +++ b/tests/auto/testlib/selftests/expected_pairdiagnostics.txt @@ -2,8 +2,8 @@ Config: Using QtTest library PASS : tst_PairDiagnostics::initTestCase() FAIL! : tst_PairDiagnostics::testQPair() Compared values are not the same - Actual (pair1): "QPair(1,1)" - Expected (pair2): "QPair(1,2)" + Actual (pair1): "std::pair(1,1)" + Expected (pair2): "std::pair(1,2)" Loc: [qtbase/tests/auto/testlib/selftests/pairdiagnostics/tst_pairdiagnostics.cpp(0)] FAIL! : tst_PairDiagnostics::testStdPair() Compared values are not the same Actual (pair1): "std::pair(1,1)" diff --git a/tests/auto/testlib/selftests/expected_pairdiagnostics.xml b/tests/auto/testlib/selftests/expected_pairdiagnostics.xml index cd98e4d36e..89e8ca49a6 100644 --- a/tests/auto/testlib/selftests/expected_pairdiagnostics.xml +++ b/tests/auto/testlib/selftests/expected_pairdiagnostics.xml @@ -12,8 +12,8 @@ + Actual (pair1): "std::pair(1,1)" + Expected (pair2): "std::pair(1,2)"]]> -- cgit v1.2.3