Merge pull request #13 from purescript-node/safe-platform

Make Node.Process.platform safe

Author: hdgarrood

src/Node/Platform.purs

@@ -5,39 +5,50 @@ module Node.Platform where
 import Prelude
 import Data.Maybe (Maybe(..))
 
+-- | See [the Node docs](https://nodejs.org/dist/latest-v6.x/docs/api/os.html#os_os_platform).
 data Platform
-  = Darwin
+  = AIX
+  | Darwin
   | FreeBSD
-  | OpenBSD
   | Linux
+  | OpenBSD
   | SunOS
   | Win32
+  | Android
 
 -- | The String representation for a platform, recognised by Node.js.
 toString :: Platform -> String
+toString AIX     = "aix"
 toString Darwin  = "darwin"
 toString FreeBSD = "freebsd"
-toString OpenBSD = "openbsd"
 toString Linux   = "linux"
+toString OpenBSD = "openbsd"
 toString SunOS   = "sunos"
 toString Win32   = "win32"
+toString Android = "android"
 
+-- | Attempt to parse a `Platform` value from a string, in the format returned
+-- | by Node.js' `process.platform`.
 fromString :: String -> Maybe Platform
+fromString "aix"     = Just AIX
 fromString "darwin"  = Just Darwin
 fromString "freebsd" = Just FreeBSD
-fromString "openbsd" = Just OpenBSD
 fromString "linux"   = Just Linux
+fromString "openbsd" = Just OpenBSD
 fromString "sunos"   = Just SunOS
 fromString "win32"   = Just Win32
+fromString "android" = Just Android
 fromString _         = Nothing
 
 instance showPlatform :: Show Platform where
+  show AIX     = "AIX"
   show Darwin  = "Darwin"
   show FreeBSD = "FreeBSD"
-  show OpenBSD = "OpenBSD"
   show Linux   = "Linux"
+  show OpenBSD = "OpenBSD"
   show SunOS   = "SunOS"
   show Win32   = "Win32"
+  show Android = "Android"
 
 derive instance eqPlatform :: Eq Platform
 derive instance ordPlatform :: Ord Platform

src/Node/Process.purs

@@ -29,7 +29,7 @@ import Control.Monad.Eff (Eff, kind Effect)
 import Control.Monad.Eff.Console (CONSOLE)
 import Control.Monad.Eff.Exception (EXCEPTION)
 
-import Data.Maybe (Maybe, fromJust)
+import Data.Maybe (Maybe)
 import Data.Posix (Pid)
 import Data.Posix.Signal (Signal)
 import Data.Posix.Signal as Signal
@@ -40,8 +40,6 @@ import Node.Platform (Platform)
 import Node.Platform as Platform
 import Node.Stream (Readable, Writable)
 
-import Partial.Unsafe (unsafePartial)
-
 import Unsafe.Coerce (unsafeCoerce)
 
 -- | An effect tracking interaction with the global `process` object.
@@ -114,8 +112,11 @@ foreign import setEnv :: forall eff. String -> String -> Eff (process :: PROCESS
 pid :: Pid
 pid = process.pid
 
-platform :: Platform
-platform = unsafePartial $ fromJust $ Platform.fromString process.platform
+platform :: Maybe Platform
+platform = Platform.fromString platformStr
+
+platformStr :: String
+platformStr = process.platform
 
 -- | Cause the process to exit with the supplied integer code. An exit code
 -- | of 0 is normally considered successful, and anything else is considered a