Boost C++ Libraries: Ticket #9419: boost::chrono::floor()/round() and negative durations is wrong

attachment set

1czajnik@… — Fri, 22 Nov 2013 11:22:41 GMT

attachment → chrono_rounding.cpp

unit test demonstrating the problem

1czajnik@… — Fri, 22 Nov 2013 11:26:56 GMT

The attached unit test demonstrates the problem, as well as a problem with round<>, which I think doesn't follow the documented rule "tie towards even" for negative values.

There are also overflow tests, and they all pass ;-)

My output of this test is:

Running 4 test cases...
../chrono_rounding.cpp(28): error in "floor_": check seconds(-2) == floor<seconds>( milliseconds(-1999) ) failed [-2 seconds != -1 second]
../chrono_rounding.cpp(29): error in "floor_": check seconds(-2) == floor<seconds>( milliseconds(-1001) ) failed [-2 seconds != -1 second]
../chrono_rounding.cpp(31): error in "floor_": check seconds(-1) == floor<seconds>( milliseconds(-999) ) failed [-1 second != 0 seconds]
../chrono_rounding.cpp(32): error in "floor_": check seconds(-1) == floor<seconds>( milliseconds(-1) ) failed [-1 second != 0 seconds]
../chrono_rounding.cpp(63): error in "round_": check seconds(-2) == round<seconds>( milliseconds(-1500) ) failed [-2 seconds != -1 second]
*** 5 failures detected in test suite "Master Test Suite"

HTH, Kris

status, summary changed

viboes — Fri, 22 Nov 2013 17:10:02 GMT

status new → assigned
summary boost::chrono::floor() and negative durations is wrong → boost::chrono::floor()/round() and negative durations is wrong

Replying to 1czajnik@…:

The attached unit test demonstrates the problem, as well as a problem with round<>, which I think doesn't follow the documented rule "tie towards even" for negative values.

There are also overflow tests, and they all pass ;-)

My output of this test is:

Running 4 test cases...
../chrono_rounding.cpp(28): error in "floor_": check seconds(-2) == floor<seconds>( milliseconds(-1999) ) failed [-2 seconds != -1 second]
../chrono_rounding.cpp(29): error in "floor_": check seconds(-2) == floor<seconds>( milliseconds(-1001) ) failed [-2 seconds != -1 second]
../chrono_rounding.cpp(31): error in "floor_": check seconds(-1) == floor<seconds>( milliseconds(-999) ) failed [-1 second != 0 seconds]
../chrono_rounding.cpp(32): error in "floor_": check seconds(-1) == floor<seconds>( milliseconds(-1) ) failed [-1 second != 0 seconds]
../chrono_rounding.cpp(63): error in "round_": check seconds(-2) == round<seconds>( milliseconds(-1500) ) failed [-2 seconds != -1 second]
*** 5 failures detected in test suite "Master Test Suite"

HTH, Kris

Thanks Kris for the report.

I would take care of it. Clearly we missed the negative numbers :(

Best, Vicente

milestone changed

viboes — Tue, 03 Dec 2013 22:49:56 GMT

milestone To Be Determined → Boost 1.56.0

status changed; resolution set

viboes — Sun, 23 Feb 2014 13:41:50 GMT

status assigned → closed
resolution → fixed

Merged to master https://github.com/boostorg/chrono/commit/143260daeb2703961448a0928d199747ca34dfca