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digitalmars.D.learn - assert in unittest has access to private member?

reply =?iso-8859-1?Q?Robert_M._M=FCnch?= <robert.muench saphirion.com> writes:
I have a case, with templates, where an assert in a unittest can access 
a private memember and I don't know how this can happen.

Before trying to creat an equivalent case, I want to cross-check, if 
assert has special semantics in a unittest so that it can access 
private memembers?

-- 
Robert M. Münch
http://www.saphirion.com
smarter | better | faster
Jun 30 2019
next sibling parent reply a11e99z <black80 bk.ru> writes:
On Sunday, 30 June 2019 at 17:24:03 UTC, Robert M. Münch wrote:

 I have a case, with templates, where an assert in a unittest 
 can access a private memember and I don't know how this can 
 happen.

 Before trying to creat an equivalent case, I want to 
 cross-check, if assert has special semantics in a unittest so 
 that it can access private memembers?


Private means that only members of the enclosing class can access 
the member, or
vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
members and functions in the same module as the enclosing class.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
did you take it into account?
Jun 30 2019
parent =?iso-8859-1?Q?Robert_M._M=FCnch?= <robert.muench saphirion.com> writes:
On 2019-06-30 17:47:27 +0000, a11e99z said:


 Private means that only members of the enclosing class can access the 
 member, or
 vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
 members and functions in the same module as the enclosing class.
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 did you take it into account?


Of course not... still to much C++ in my head... Thanks for the 
clarification. I will remember it from now on.

-- 
Robert M. Münch
http://www.saphirion.com
smarter | better | faster
Jul 01 2019
prev sibling next sibling parent XavierAP <n3minis-git yahoo.es> writes:
On Sunday, 30 June 2019 at 17:24:03 UTC, Robert M. Münch wrote:

 I have a case, with templates, where an assert in a unittest 
 can access a private memember and I don't know how this can 
 happen.


Modules are the units of encapsulation in D:

https://dlang.org/spec/attribute.html#visibility_attributes
Jun 30 2019
prev sibling parent Jonathan M Davis <newsgroup.d jmdavisprog.com> writes:
On Sunday, June 30, 2019 11:24:03 AM MDT Robert M. Münch via Digitalmars-d-
learn wrote:

 I have a case, with templates, where an assert in a unittest can access
 a private memember and I don't know how this can happen.

 Before trying to creat an equivalent case, I want to cross-check, if
 assert has special semantics in a unittest so that it can access
 private memembers?


I know that there at least used to be a bug where templates were treated as
public instead of private, though I thought that that was fixed some time
ago. Regardless, as the others have pointed out, private in D is private to
the module, not the class or struct or template or whatever. So, if your
unittest block is in the same module as what you're testing, it legitimately
has access to all private members, and that's not a bug. On the other hand,
if your unittest block is in another module from the declaration, and it's
accessing a private member, that that is a bug unless you're using template
mixins to mix the code into the current module.

D treats the module as the unit of encapsulation so that it doesn't have to
worry about having features like C++'s friend, and in general, this has
worked out extremeley well, though it tends to surprise many people at
first, since many (most?) don't read the documentation carefully enough and
assume that private is private to the class as it is in many other
languages:

https://dlang.org/spec/attribute.html#visibility_attributes

Certainly, it's great in general that unittest blocks can access private in
the same module, because it makes it easy to test private functions without
having to alter the API of your class like you would with something like
JUnit in Java. If for some reason, you really do need something to not have
access to private members, then you need to put it in a separate module.

- Jonathan M Davis
Jun 30 2019