Use EnumVariable for choice-based build options.

SConstruct

@@ -132,10 +132,10 @@ opts = Variables(customs, ARGUMENTS)
 
 # Target build options
 opts.Add('arch', "Platform-dependent architecture (arm/arm64/x86/x64/mips/etc)", '')
-opts.Add('bits', "Target platform bits (default/32/64/fat)", 'default')
+opts.Add(EnumVariable('bits', "Target platform bits", 'default', ('default', '32', '64', 'fat')))
 opts.Add('p', "Platform (alias for 'platform')", '')
-opts.Add('platform', "Target platform: any in " + str(platform_list), '')
-opts.Add('target', "Compilation target (debug/release_debug/release)", 'debug')
+opts.Add('platform', "Target platform (%s)" % ('|'.join(platform_list), ), '')
+opts.Add(EnumVariable('target', "Compilation target", 'debug', ('debug', 'release_debug', 'release')))
 opts.Add('tools', "Build the tools a.k.a. the Godot editor (yes/no)", 'yes')
 
 # Components
@@ -152,7 +152,7 @@ opts.Add('extra_suffix', "Custom extra suffix added to the base filename of all
 opts.Add('unix_global_settings_path', "UNIX-specific path to system-wide settings. Currently only used for templates", '')
 opts.Add('verbose', "Enable verbose output for the compilation (yes/no)", 'no')
 opts.Add('vsproj', "Generate Visual Studio Project. (yes/no)", 'no')
-opts.Add('warnings', "Set the level of warnings emitted during compilation (extra/all/moderate/no)", 'no')
+opts.Add(EnumVariable('warnings', "Set the level of warnings emitted during compilation", 'no', ('extra', 'all', 'moderate', 'no')))
 opts.Add('progress', "Show a progress indicator during build (yes/no)", 'yes')
 opts.Add('dev', "If yes, alias for verbose=yes warnings=all (yes/no)", 'no')
 
@@ -186,7 +186,7 @@ opts.Add("LINKFLAGS", "Custom flags for the linker")
 for k in platform_opts.keys():
     opt_list = platform_opts[k]
     for o in opt_list:
-        opts.Add(o[0], o[1], o[2])
+        opts.Add(o)
 
 for x in module_list:
     opts.Add('module_' + x + '_enabled', "Enable module '" + x + "' (yes/no)", "yes")

platform/android/detect.py

@@ -18,11 +18,12 @@ def can_build():
 
 
 def get_opts():
+    from SCons.Variables import EnumVariable
 
     return [
         ('ANDROID_NDK_ROOT', 'Path to the Android NDK', os.environ.get("ANDROID_NDK_ROOT", 0)),
         ('ndk_platform', 'Target platform (android-<api>, e.g. "android-18")', "android-18"),
-        ('android_arch', 'Target architecture (armv7/armv6/arm64v8/x86)', "armv7"),
+        EnumVariable('android_arch', 'Target architecture', "armv7", ('armv7', 'armv6', 'arm64v8', 'x86')),
         ('android_neon', 'Enable NEON support (armv7 only)', "yes"),
         ('android_stl', 'Enable Android STL support (for modules)', "no")
     ]

platform/haiku/detect.py

@@ -19,9 +19,10 @@ def can_build():
 
 
 def get_opts():
+    from SCons.Variables import EnumVariable
 
     return [
-        ('debug_symbols', 'Add debug symbols to release version (yes/no/full)', 'yes')
+        EnumVariable('debug_symbols', 'Add debug symbols to release version', 'yes', ('yes', 'no', 'full')),
     ]
 
 

platform/osx/detect.py

@@ -19,10 +19,11 @@ def can_build():
 
 
 def get_opts():
+    from SCons.Variables import EnumVariable
 
     return [
         ('osxcross_sdk', 'OSXCross SDK version', 'darwin14'),
-        ('debug_symbols', 'Add debug symbols to release version (yes/no/full)', 'yes'),
+        EnumVariable('debug_symbols', 'Add debug symbols to release version', 'yes', ('yes', 'no', 'full')),
     ]
 
 

platform/windows/detect.py

@@ -49,6 +49,7 @@ def can_build():
 
 
 def get_opts():
+    from SCons.Variables import EnumVariable
 
     mingw32 = ""
     mingw64 = ""
@@ -65,7 +66,7 @@ def get_opts():
         ('mingw_prefix_32', 'MinGW prefix (Win32)', mingw32),
         ('mingw_prefix_64', 'MinGW prefix (Win64)', mingw64),
         ('use_lto', 'Use link time optimization (when using MingW)', 'no'),
-        ('debug_symbols', 'Add debug symbols to release version (yes/no/full)', 'yes')
+        EnumVariable('debug_symbols', 'Add debug symbols to release version', 'yes', ('yes', 'no', 'full')),
     ]
 
 

platform/x11/detect.py

@@ -45,6 +45,7 @@ def can_build():
     return True
 
 def get_opts():
+    from SCons.Variables import EnumVariable
 
     return [
         ('use_llvm', 'Use the LLVM compiler', 'no'),
@@ -54,7 +55,7 @@ def get_opts():
         ('use_lto', 'Use link time optimization', 'no'),
         ('pulseaudio', 'Detect & use pulseaudio', 'yes'),
         ('udev', 'Use udev for gamepad connection callbacks', 'no'),
-        ('debug_symbols', 'Add debug symbols to release version (yes/no/full)', 'yes')
+        EnumVariable('debug_symbols', 'Add debug symbols to release version', 'yes', ('yes', 'no', 'full')),
     ]