diff options
author | Thiago Macieira <thiago.macieira@intel.com> | 2014-10-31 16:28:47 -0700 |
---|---|---|
committer | Thiago Macieira <thiago.macieira@intel.com> | 2014-11-20 05:46:40 +0100 |
commit | 849604e2f98296ddcde4f1e323e2383ef4f0dd49 (patch) | |
tree | 5b51224f8bb2b1f6eb6ba83762f6d8bd59eefd0f /src/corelib/kernel/qvariant.cpp | |
parent | 8153386397087ce4f5c8997992edf5c1fd38b8db (diff) |
Fix asymmetry in QVariant::cmp when A converts to B but not the opposite
This would result in (a == b) != (b == a). The == operation should be
commutative as much as possible.
Now, there's still an asymmetry in that b is forced to a type and the
conversion may fail. QVariant should have an idea of what conversions
are "promotion" and which ones are "demotion" (subject to loss of data
and/or can fail), so it can do the promotion first
Task-number: QTBUG-42254
Change-Id: I9fa4496bbbf0f8719ff8456cc24247290beac608
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@digia.com>
Diffstat (limited to 'src/corelib/kernel/qvariant.cpp')
-rw-r--r-- | src/corelib/kernel/qvariant.cpp | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/src/corelib/kernel/qvariant.cpp b/src/corelib/kernel/qvariant.cpp index 73a951c39b..67911f2836 100644 --- a/src/corelib/kernel/qvariant.cpp +++ b/src/corelib/kernel/qvariant.cpp @@ -3161,8 +3161,15 @@ bool QVariant::cmp(const QVariant &v) const else return toLongLong() == v.toLongLong(); } - if (!v2.canConvert(v1.d.type) || !v2.convert(v1.d.type)) - return false; + if (v2.canConvert(v1.d.type)) { + if (!v2.convert(v1.d.type)) + return false; + } else { + // try the opposite conversion, it might work + qSwap(v1, v2); + if (!v2.convert(v1.d.type)) + return false; + } } if (v1.d.type >= QMetaType::User) { int result; |