On Tue, 19 Oct 2010 05:04:03 -0400, Jens Mueller <[email protected]>
wrote:
Hi,
I have a simply example using imports that confuses me. Unfortunately I
cannot find explanation on the web site.
File a.d:
module a;
// some import here
//import std.conv;
File b.d:
module b;
import a;
void main() {
}
I do a
$ dmd -run b.d
and that works as expected.
If I commented in 'import std.conv;' in file a.d and do
$ dmd -run b.d
linking fails with
"b.o:(.data+0xc): undefined reference to `_D1a12__ModuleInfoZ'"
I figured out that I need to add a.d like this
$ dmd a.d -run b.d
Because the ModuleInfo for a.d needs to be generated.
So much for my limited understanding.
In my use case I want to do unit testing like this
$ dmd -unittest -run b.d
It seems that I always have to built a library to make sure that an
import works. Can somebody explain the rational behind that? What is
ModuleInfo? And why is it needed? How can I make the unit testing work
per module? How do you do it?
I think I missed something essential about imports.
ModuleInfo is the runtime representation of the module. Modules can have
their own constructors and destructors to initialize global and
thread-local data. You can also get the name of the module from the
module info. They are stored by the compiler in an array that is
accessible at runtime. A module's unit tests are also stored in the
module info.
To answer your other questions, just unit test everything at once. There
is no need to run each individual file. In other words, just do:
dmd -unittest -run b.d a.d
And that will test all unittests in b and a.
If you insist on only testing unittests in b, you still need a complete
program. So a's module info must be included. Therefore you need to do a
partial compilation:
dmd -c a.d
this creates a.o (or a.obj depending on your platform). If a has
unittests they are *not* included in the object file.
dmd -unittest -run b.d a.o
Note that I'm passing the already-compiled version of a, this means it
will not be recompiled to add a's unit tests. Why you'd want to do it
this way, I have no idea.
-Steve
