Added support for poison to the lexer and parser (and associated tests)

frontends/LexRain.x

@@ -42,7 +42,7 @@ $hexDigit = [0-9 a-f A-F]
           | "return" | "now"
           | "wait" | "for" | "until"
           | "if" | "while" | "else"
-          | "pri" | "alt"
+          | "pri" | "alt" | "poison"
           | "sint8" | "sint16" | "sint32" | "sint64"
           | "uint8" | "uint16" | "uint32" | "uint64"
           | "int" | "bool" | "time" | "channel"

frontends/ParseRain.hs

@@ -56,7 +56,7 @@ instance Die (GenParser tok st) where
 sLeftQ, sRightQ, sLeftR, sRightR, sLeftC, sRightC, sSemiColon, sColon,
   sComma, sIn, sOut, sDots, sPar, sSeq, sAlt, sPri, sSeqeach, sPareach,
   sChannel, sOne2One, sIf, sElse, sWhile, sProcess, sFunction, sReturn,
-  sWait, sFor, sUntil :: RainParser Meta
+  sWait, sFor, sUntil, sPoison :: RainParser Meta
 
 --{{{ Symbols
 sLeftQ = reserved "["
@@ -92,6 +92,7 @@ sReturn = reserved "return"
 sWait = reserved "wait"
 sFor = reserved "for"
 sUntil = reserved "until"
+sPoison = reserved "poison"
 --}}}
 
 --{{{Operators
@@ -462,6 +463,7 @@ statement
       rainTimerName) wm}
     <|> try (comm False)
     <|> alt
+    <|> do {m <- sPoison ; ch <- lvalue; sSemiColon ; return $ A.InjectPoison m ch}
     <|> try (do { lv <- lvalue ; op <- assignOp ; exp <- expression ; sSemiColon ; 
              case op of 
                (m', Just dyOp) -> return (A.Assign m' [lv] (A.ExpressionList m' [(A.Dyadic m' dyOp (A.ExprVariable (findMeta lv) lv) exp)]))

frontends/ParseRainTest.hs

@@ -731,7 +731,18 @@ testTime =
  ]
  where
    timer = mVariable RP.rainTimerName
-        
+
+testPoison :: [ParseTest A.Process]
+testPoison =
+ [
+  pass ("poison x;", RP.statement, assertPatternMatch "testPoison 0" $
+    mInjectPoison $ variablePattern "x")
+  ,fail ("poison 0;", RP.statement)
+  ,fail ("poison 0", RP.statement)
+  ,fail ("poison;", RP.statement)
+  ,fail ("poison", RP.statement)
+ ]
+
 --Returns the list of tests:
 tests :: Test
 tests = TestLabel "ParseRainTest" $ TestList
@@ -752,6 +763,7 @@ tests = TestLabel "ParseRainTest" $ TestList
   parseTests testTime,
   parseTests testRun,
   parseTests testDecl,
+  parseTests testPoison,
   parseTests testTopLevelDecl
  ]
 --TODO test: