BLD: clean up library and test build configuration.

Use separate scons environment for linking libdiffpy with extra
libraries.  Simplify setup of header search path and library
dependencies when building the alltests test program.

Author: pavoljuhas

src/SConscript

@@ -8,9 +8,6 @@ Import('env')
 flagnames = 'CFLAGS CXXFLAGS LDFLAGS'.split()
 env.MergeFlags([os.environ.get(n, '') for n in flagnames])
 
-# The directory of this SConscript should be searched first for any headers.
-env.PrependUnique(CPPPATH=Dir('.'))
-
 # Insert LIBRARY_PATH explicitly because some compilers
 # ignore it in the system environment.
 env.PrependUnique(LIBPATH=env['ENV'].get('LIBRARY_PATH', '').split(':'))
@@ -24,11 +21,6 @@ if env['tool'] == 'intelc':
         Exit(1)
     env.Tool('intelc', topdir=icpc[:icpc.rfind('/bin')])
 
-# Declare external libraries.
-env.ParseConfig("gsl-config --cflags --libs")
-# dladdr in runtimepath.cpp requires the dl library.
-env.AppendUnique(LIBS=['dl'])
-
 fast_linkflags = ['-s']
 
 # Platform specific intricacies.
@@ -90,6 +82,10 @@ if build_tests and env['test_installed']:
     SConscript('tests/SConscript')
     Return()
 
+# Here we do not test the installed library.  Any diffpy headers
+# should thus be looked up from our source tree.
+env.PrependUnique(CPPPATH=Dir('.'))
+
 # Load the version script first to resolve the majorminor tuple
 SConscript('diffpy/SConscript.version')
 
@@ -110,7 +106,15 @@ if 'sdist' in COMMAND_LINE_TARGETS:
 # Top Level Targets ----------------------------------------------------------
 
 # lib -- shared library object
-libdiffpy = env.SharedLibrary('diffpy', env['lib_sources'])
+
+# use new environment with extra libraries needed for libdiffpy.
+env_lib = env.Clone()
+# Setup GSL, the GNU Scientific library.
+env_lib.ParseConfig("gsl-config --cflags --libs")
+# The dladdr call in runtimepath.cpp requires the dl library.
+env_lib.AppendUnique(LIBS=['dl'])
+
+libdiffpy = env_lib.SharedLibrary('diffpy', env['lib_sources'])
 Export('libdiffpy')
 lib = Alias('lib', [libdiffpy, env['lib_includes']])
 Default(lib)

src/tests/SConscript

@@ -9,7 +9,6 @@ env_test.Tool('cxxtest')
 
 if env['test_installed']:
     # build unit tests for the installed library
-    env_test['CPPPATH'].remove(Dir('..'))
     env_test.PrependUnique(CPPPATH=env['includedir'], delete_existing=1)
     lib_dir = env['libdir']
 else:
@@ -21,11 +20,6 @@ use_our_library = not env['test_installed']
 env_test.PrependUnique(LIBS='diffpy', LIBPATH=lib_dir, delete_existing=1)
 env_test.PrependUnique(LINKFLAGS="-Wl,-rpath,%r" % lib_dir)
 
-# Use only libraries needed for building the unit tests.
-pat = 'diffpy|boost_serialization|ObjCryst'
-keeplibs = lambda s: re.search(pat, str(s))
-env_test.Replace(LIBS=filter(keeplibs, env_test['LIBS']))
-
 # Targets --------------------------------------------------------------------
 
 def srcsupported(f):