Reworking of lapack_shared_libs and similar properties (#1682)

* Turned <provider>_libs into an iterable

Modifications :
- added class LibraryList + unit tests
- added convenience functions `find_libraries` and `dedupe`
- modifed non Intel blas/lapack providers
- modified packages using blas_shared_libs and similar functions

* atlas : added pthread variant

* intel packages : added lapack_libs and blas_libs

* find_library_path : removed unused function

* PR review : fixed last issues

* LibraryList : added test on __add__ return type

* LibraryList : added __radd__ fixed unit tests

fix : failing unit tests due to missing `self`

* cp2k and dependecies : fixed blas-lapack related statements in package.py

var/spack/repos/builtin/packages/openblas/package.py

@@ -30,7 +30,7 @@
 class Openblas(Package):
     """OpenBLAS: An optimized BLAS library"""
     homepage = "http://www.openblas.net"
-    url      = "http://github.com/xianyi/OpenBLAS/archive/v0.2.15.tar.gz"
+    url = "http://github.com/xianyi/OpenBLAS/archive/v0.2.15.tar.gz"
 
     version('0.2.19', '28c998054fd377279741c6f0b9ea7941')
     version('0.2.18', '805e7f660877d588ea7e3792cda2ee65')
@@ -51,6 +51,17 @@ class Openblas(Package):
 
     patch('make.patch')
 
+    @property
+    def blas_libs(self):
+        shared = True if '+shared' in self.spec else False
+        return find_libraries(
+            ['libopenblas'], root=self.prefix, shared=shared, recurse=True
+        )
+
+    @property
+    def lapack_libs(self):
+        return self.blas_libs
+
     def install(self, spec, prefix):
         # As of 06/2016 there is no mechanism to specify that packages which
         # depends on Blas/Lapack need C or/and Fortran symbols. For now
@@ -100,6 +111,9 @@ def install(self, spec, prefix):
         # no quotes around prefix (spack doesn't use a shell)
         make('install', "PREFIX=%s" % prefix, *make_defs)
 
+        # TODO : the links below are mainly there because client
+        # TODO : packages are wrongly written. Check if they can be removed
+
         # Blas virtual package should provide blas.a and libblas.a
         with working_dir(prefix.lib):
             symlink('libopenblas.a', 'blas.a')
@@ -120,21 +134,6 @@ def install(self, spec, prefix):
         # test.
         self.check_install(spec)
 
-    def setup_dependent_package(self, module, dspec):
-        # This is WIP for a prototype interface for virtual packages.
-        # We can update this as more builds start depending on BLAS/LAPACK.
-        libdir = find_library_path('libopenblas.a',
-                                   self.prefix.lib64,
-                                   self.prefix.lib)
-
-        self.spec.blas_static_lib   = join_path(libdir, 'libopenblas.a')
-        self.spec.lapack_static_lib = self.spec.blas_static_lib
-
-        if '+shared' in self.spec:
-            self.spec.blas_shared_lib   = join_path(libdir, 'libopenblas.%s' %
-                                                    dso_suffix)
-            self.spec.lapack_shared_lib = self.spec.blas_shared_lib
-
     def check_install(self, spec):
         source_file = join_path(os.path.dirname(self.module.__file__),
                                 'test_cblas_dgemm.c')