Remove copy/assign/move tests in testAttributes() #1922
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When we implemented the "rule of 5" (PR AcademySoftwareFoundation#601) in 2019, I added code to testAttributes.cpp to validate the behavior, specifically related to the TypedAttribute class, but in retrospect, this code isn't reliable, so I propose eliminating the test altogether. The test counts invocations of the various constructors, destructors, and move/assignment operators, expecting them to be consistent, but compilers can optionally optimize some of these operations away, producing inconsistent results. In particular, a Debug build on Windows produces different results from a Release build. Our CI has not historically tested a Windows Debug build, which explains why we never caught this. The exact behavior may have also changed with C++17. All the more reason to avoid such picky tests. This does not change the library code, only the tests. Signed-off-by: Cary Phillips <[email protected]>
lgritz
approved these changes
Nov 20, 2024
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When we implemented the "rule of 5" (PR #601) in 2019, I added code to testAttributes.cpp to validate the behavior, specifically related to the TypedAttribute class, but in retrospect, this code isn't reliable, so I propose eliminating the test altogether.
The test counts invocations of the various constructors, destructors, and move/assignment operators, expecting them to be consistent, but compilers can optionally optimize some of these operations away, producing inconsistent results.
In particular, a Debug build on Windows produces different results from a Release build. In particular, this code:
invokes the move constructor in debug, but a "Release" build optimizes the object away entirely.
Our CI has not historically tested a Windows Debug build, which explains why we never caught this. The exact behavior may have also changed with C++17. All the more reason to avoid such picky tests.
This does not change the library code, only the tests that I added in #601 in 2019.