tests: Clean up how the sanity test is scheduled

I created a new function for checking if a group of tests is running to
help determine if the sanity test needs to run before anything else.

Signed-off-by: Anna Schumaker <Anna@OcarinaProject.net>

tests/Sconscript

@@ -3,16 +3,22 @@ import sys, os
 Import("env")
 
 tests = []
-check_sanity = False
+
 for arg in sys.argv[1:]:
 	if arg.find("tests") == 0:
 		tests += [ arg ]
-		if arg in set(["tests", "tests/", "tests/sanity"]):
-			check_sanity = True
 
 if len(tests) == 0:
 	Return()
 
+def testing_group(group):
+	group = [ "tests" ] + group
+	for arg in tests:
+		if arg in set(group + [ g + "/" for g in group]):
+			return True
+	return False
+check_sanity = testing_group([])
+
 env.Append(CCFLAGS = "-DCONFIG_TESTING")
 env.UsePackage("glib-2.0")
 test_o = env.Object("test", "test.c")
@@ -24,14 +30,14 @@ def UnitTest(test, sources):
 	Depends(run, make)
 	Alias("tests/%s" % test, run)
 	return run
-Export("UnitTest")
+Export("UnitTest", "testing_group")
 
 #Generate empty audio files
 SConscript("Music/Sconscript")
 
-res = SConscript("core/Sconscript")
+res  = UnitTest("sanity", [ "sanity.c" ])
+res += SConscript("core/Sconscript")
 if check_sanity == True:
-	res = [ UnitTest("sanity", [ "sanity.c" ]) ] + res
 	for t in res[1:]:
 		Depends(t, res[0])