Fix mocking of interface which extend Throwable

[DeepDiver1975]

fixes sebastianbergmann/phpunit#2995

[DeepDiver1975]

Issue reproduced in https://travis-ci.org/sebastianbergmann/phpunit-mock-objects/jobs/338651530

[codecov-io]

Codecov Report

Merging #402 into master will increase coverage by 0.17%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##             master     #402      +/-   ##
============================================
+ Coverage     72.77%   72.95%   +0.17%     
- Complexity      436      438       +2     
============================================
  Files            27       27              
  Lines          1227     1235       +8     
============================================
+ Hits            893      901       +8     
  Misses          334      334

Impacted Files	Coverage Δ	Complexity Δ
src/Generator.php	85.03% <100%> (+0.23%)	177 <0> (+2)	⬆️

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[DeepDiver1975]

@sebastianbergmann can I drag your attention to this PR? ;-) THX a lot!

[sebastianbergmann]

Throwable is not supposed to be implemented in userland (I know that PHP allows it, which is unfortunate). I am not convinced that it would be "good" for PHPUnit to support this.

That being said, can you elaborate why you implement Throwable in your code instead of extending Exception?

[DeepDiver1975]

That being said, can you elaborate why you implement Throwable in your code instead of extending Exception?

We are trying to mock dbal's Doctrine\DBAL\Driver\DriverException which is an interface.
https://github.com/doctrine/dbal/blob/2.6/lib/Doctrine/DBAL/Driver/DriverException.php#L32

See owncloud/core@1a5e980 - in the workaround I switched to Doctrine\DBAL\Driver\AbstractDriverException

[DeepDiver1975]

FYI: Back in 2.5 the interface did not inherit from \Throwable - https://github.com/doctrine/dbal/blob/2.5/lib/Doctrine/DBAL/Driver/DriverException.php#L32

[sebastianbergmann]

@Ocramius @beberlei Can you explain why Doctrine does this? Thanks!

[Ocramius]

Throwable is not implemented in userland, it is just implemented as part of extends Exception:

interface SomeException extends Throwable // correct semantics, otherwise it can't be an exception anyway
{
}

class MyException extends OutOfBoundsException implements SomeException
{
}

The change is just semantic.

From my PoV, it makes no sense to mock a Throwable, as a collaborator will unlikely ever be a Throwable .

What PHPUnit would have to do (if mocking is needed) is extending Exception in the mock when Throwable is detected as implemented interface.

[Ocramius]

What PHPUnit would have to do (if mocking is needed) is extending Exception in the mock when Throwable is detected as implemented interface.

Ah, I see that this patch already does that :)

Also, re-thinking about the "makes no sense to mock a Throwable", it makes sense if the "auto-mocking on return types" kicks in on a foo() : Throwable

[sebastianbergmann]

Thank you for the explanation, @Ocramius.

[sebastianbergmann]

And thank you, @DeepDiver1975, for the patch! :-)

[DeepDiver1975]

And thank you, @DeepDiver1975, for the patch! :-)

my pleasure - happy to contribute back to a tool we use for years!