mpich, mvapich2: fixed setup_*_environment (#18032)

fixes #18028

Since now external packages support multiple modules
the correct thing to do is to check if the name of the
*first* module to be loaded contains the string "cray"

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

@@ -187,7 +187,8 @@ def setup_run_environment(self, env):
         # their run environments the code to make the compilers available.
         # For Cray MPIs, the regular compiler wrappers *are* the MPI wrappers.
         # Cray MPIs always have cray in the module name, e.g. "cray-mpich"
-        if self.spec.external_modules and 'cray' in self.spec.external_modules:
+        external_modules = self.spec.external_modules
+        if external_modules and 'cray' in external_modules[0]:
             env.set('MPICC', spack_cc)
             env.set('MPICXX', spack_cxx)
             env.set('MPIF77', spack_fc)
@@ -210,7 +211,8 @@ def setup_dependent_build_environment(self, env, dependent_spec):
     def setup_dependent_package(self, module, dependent_spec):
         # For Cray MPIs, the regular compiler wrappers *are* the MPI wrappers.
         # Cray MPIs always have cray in the module name, e.g. "cray-mpich"
-        if self.spec.external_modules and 'cray' in self.spec.external_modules:
+        external_modules = self.spec.external_modules
+        if external_modules and 'cray' in external_modules[0]:
             self.spec.mpicc = spack_cc
             self.spec.mpicxx = spack_cxx
             self.spec.mpifc = spack_fc

var/spack/repos/builtin/packages/mvapich2/package.py

@@ -240,7 +240,8 @@ def setup_dependent_build_environment(self, env, dependent_spec):
     def setup_compiler_environment(self, env):
         # For Cray MPIs, the regular compiler wrappers *are* the MPI wrappers.
         # Cray MPIs always have cray in the module name, e.g. "cray-mvapich"
-        if self.spec.external_modules and 'cray' in self.spec.external_modules:
+        external_modules = self.spec.external_modules
+        if external_modules and 'cray' in external_modules[0]:
             env.set('MPICC',  spack_cc)
             env.set('MPICXX', spack_cxx)
             env.set('MPIF77', spack_fc)
@@ -254,7 +255,8 @@ def setup_compiler_environment(self, env):
     def setup_dependent_package(self, module, dependent_spec):
         # For Cray MPIs, the regular compiler wrappers *are* the MPI wrappers.
         # Cray MPIs always have cray in the module name, e.g. "cray-mvapich"
-        if self.spec.external_modules and 'cray' in self.spec.external_modules:
+        external_modules = self.spec.external_modules
+        if external_modules and 'cray' in external_modules[0]:
             self.spec.mpicc = spack_cc
             self.spec.mpicxx = spack_cxx
             self.spec.mpifc = spack_fc