[Test] BOOST_CHECK_EQUAL can't compare scoped enumerations
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I'm running Windows 10, 64-bit, MinGW64 with GCC 5.3 64-bit, and
BOOST_1_60_0 64-bit.
Here is the stripped down version of what's failing:
enum class UsedFor { NOTIFY_INPUT, CONST_INPUT, VAR_INPUT,
NOTIFY_RESULT, VAR_RESULT};
UsedFor mUse = UsedFor::NOTIFY_INPUT;
BOOST_CHECK(mUse == Operand::UsedFor::NOTIFY_INPUT);
// BOOST_CHECK_EQUAL(mUse, Operand::UsedFor::NOTIFY_INPUT);
If BOOST_CHECK_EQUAL() is commented out, BOOST_CHECK() complies and
executes without error.
However,
// BOOST_CHECK(mUse == Operand::UsedFor::NOTIFY_INPUT);
BOOST_CHECK_EQUAL(mUse, Operand::UsedFor::NOTIFY_INPUT);
If BOOST_CHECK() is comment out, BOOST_CHECK_EQUAL() gets a template
barf with the general comment, " template argument
deduction/substitution failed:". Here are some of the complaints:
D:\Boost_1_60_0/boost/test/tools/detail/print_helper.hpp:50:14: note:
cannot convert 't' (type 'const
DiGSE::Operand_Class_Test_Suite::Operand_Default_Constructor_Test::test_method()::UsedFor')
to type 'std::_Setw'
ostr << t;
^
D:/Program
Files/mingw-w64/x86_64-5.3.0-posix-seh-rt_v4-rev0/mingw64/x86_64-w64-mingw32/include/c++/iomanip:208:5:
note: candidate: template
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Merrill Cornish
The simple answer is this: scoped enums are not printable (unlike old enums). Error message is a bit messy, but the good news is that I've checked in the change few days ago which will make it much more clear. Gennadiy
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scoped enums are not printable I've already run into that problem, so I wrote an inline function, enum2int(), to do a static_cast to int when I have to print one. But
On 2/4/2016 9:03 PM, Gennadiy Rozental wrote: that aside, why does BOOST_CHECK(mUse == UsedFor::NOTIFY_INPUT); appear to work. Some of your documentation implies that BOOST_CHECK_EQUAL(L, R) is equivalent to BOOST_CHECK(L == R), but it doesn't act that way, and Eclipse's expansion of BOOST_CHECK_EQUAL() shows a lot more than L++R. Merrill Cornish
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Merrill Cornish
On 2/4/2016 9:03 PM, Gennadiy Rozental wrote:
scoped enums are not printable I've already run into that problem, so I wrote an inline function, enum2int(), to do a static_cast to int when I have to print one.
Why not implement operator<
But that aside, why does BOOST_CHECK(mUse == UsedFor::NOTIFY_INPUT); appear to work.
As it should.
Some of your documentation implies that BOOST_CHECK_EQUAL(L, R) is equivalent to BOOST_CHECK(L == R),
In spirit. The difference is that BOOST_CHECK_EQUAL attempts to report mismatched values. In any case you should start using BOOST_TEST(a==b) for all your assertions. Gennadiy
participants (2)
-
Gennadiy Rozental
-
Merrill Cornish