Posix: Add default SONAME/install_name for dynamic libraries ...

Setting it to the filename (ELF) or `@rpath/<file name>` (Mach-O).

This seems to be required in order to use the libraries copied to
the output directory of dependees - either by setting the
LD_LIBRARY_PATH env var when starting the executable, or baking a
RUNPATH into the executable (e.g., via `patchelf --set-rpath` for
deployment).

Otherwise the loader tries to load the library from the original
location specified in the linking cmdline, which is some
`<path to dep pkg>/.dub/…` path (and apparently potentially
relative, and thus even more brittle). For ELF, I would assume
that all SONAME + DT_NEEDED entries (of executable + all .so libs)
would need to be post-processed to enable loading the libs from the
executable's directory (well, any non-original location).

update version to v1.29.2-beta.1

Temporarily disable ldc-master as the dustmite test is broken

CI: Update versions of dub for fetch test ...

Those versions are old and broken with the latest compiler,
hence dub run will fail. Use the three most recent versions
(at the time of writing) to solve this issue.

PackageManager: Move class' extra searchPath/Package to an internal location ...

Those fields have been aggregated in Location and them being in `PackageManager`
stands out as a double duty (the `PackageManager` is both a `Location`
and act as a `Location` manager). By using a `Location` for them we can
start to streamline the code.

Use configy library to parse dub.json file ...

This will provide a vastly superior UX to the users:
- They will be warned about typos;
- The type information provided will be more accurate and always include file/line infos
  (e.g. no more 'Invalid SemVer versions');
- We can expose a better recipe struct to library users on the long run,
  by separating the actual data DUB uses from what it reads;
- We can be more descriptive about errors / intent, for example by using `SetInfo`;

Trivial: Convert some spaces to tabs

Trivial: Remove always-true condition ...

isExactVersion will never return true if repository.empty returns false.

Trivial: Remove test about the internals of Dependency ...

Now that Dependency is a proper SumType, this can never happen.

Trivial: Remove redundant comparison ...

optional and default_ are indeed checked by opEquals.

Trivial: Correct code to use match's value instead of property ...

This code was accidentally working as it was calling the path property,
essentially entering another match on the SumType.

Trivial: Remove dead import

Remove 'unknown' version ...

It was never used.

Dependency: Deprecate path/repository setters ...

There is no real use case for changing a dependency in place,
instead we better let the user overwrite the dependency itself.

initPackage: Use VersionRange instead of string

Merge pull request #2435 from Geod24/getBestPackage-redundancy ...

Remove redundant lookup when searching for a tool

Signed-off-by: Nicholas Wilson <thewilsonator@users.noreply.github.com>
Merged-on-behalf-of: Nicholas Wilson <thewilsonator@users.noreply.github.com>

remove unneccessary warning prefix ...

logWarn already adds a warning

Remove redundant lookup for tools package ...

Because the first call to getBestPackage will use VersionRange.Any,
it will match whatever the second call would match, but the second
call will only happen if there is no match, hence it should not be
possible that the second call ever returns something.

Trivial: Remove superfluous argument to getBestPackage ...

It's already the default.

Integrate `dependencyBuildSettings` into dependencies ...

Because those are specified in `dependencies`,
they should be stored alongside them.
Unfortunately this will slihtly increase memory usage in the common case,
but unlikely to a point where it would be problematic.

This is technically a breaking change as a field is getting removed,
however this struct has been manipulated a few times in breaking ways,
and it's unlikely `dependencyBuildSettings` is being used outside of dub,
given how recent it is and how narrow its usage is.
However, as `dependencies` is likely to be widely used, a compatibility
type and an `alias this` are provided not to break client code.

D-YAML: Sync with v0.9.2 release

Dub: Introduce a class to use in unittests ...

Currently, unit tests for dub fails on my machine
as I have a custom registry configured. This is a great
example as to why unittests shouldn't do IO or depend on the
environment, as they can randomly fail. The new TestDub class,
private to dub-application at the moment, is a band-aid for this.
I am hoping that over time, we can perform more dependency injection
with the same method as used here (or by providing a class that encloses
all IO) so that we do not need to subclass Dub.

Windows: Don't copy import .lib & .exp files for executables ...

One aspect of issue #2377 - copy those for DLLs only.

Remove redundant null checks in DependencyVersionResolver ...

We're never passing null because if we were, a SEGV would happen earlier.
But just in case, add a few asserts.

add $DPATH environment variable for file locations (#2281) ...

* error out on unknown environment variables

* add env + config for package + settings locations

fix #229

* adjust to review, extend $DPATH test

* review round 2

Merge pull request #2424 from WebFreak001/avoid-extra-mainfile-scan ...

only do main file searching when neccessary

Signed-off-by: Nicholas Wilson <thewilsonator@users.noreply.github.com>
Merged-on-behalf-of: Nicholas Wilson <thewilsonator@users.noreply.github.com>

PackageManager: Deprecate overloads of getPackage with string version

reduce FS access count for main file generation ...

as all the sourcePaths are checked and the last one is used, we just go
through all the sourcePaths in reverse and break when the first one is
found.

only do main file searching when neccessary

Trivial: Expand body of Dependency.opEquals ...

While the m_value difference is the common case,
the other ones need to be checked as well,
so put them first as they are cheaper.
Additionally, having three expressions on a single
return is not ideal for coverage / break,
so split it into 3 lines.