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|
module Main
where
import Data.Maybe
import System.Exit
import Test.HUnit
import Text.XML.HXT.Core
-- ------------------------------------------------------------
--
-- a somewhat complex data structure
-- for representing programs of a simple
-- imperative language
type Program = Stmt
type StmtList = [Stmt]
data Stmt
= Assign Ident Expr
| Stmts StmtList
| If Expr Stmt (Maybe Stmt)
| While Expr Stmt
deriving (Eq, Show)
type Ident = String
data Expr
= IntConst Int
| BoolConst Bool
| Var Ident
| UnExpr UnOp Expr
| BinExpr Op Expr Expr
deriving (Eq, Show)
data Op
= Add | Sub | Mul | Div | Mod | Eq | Neq
deriving (Eq, Ord, Enum, Show)
data UnOp
= UPlus | UMinus | Neg
deriving (Eq, Ord, Read, Show)
-- ------------------------------------------------------------
--
-- the pickler definition for the data types
-- the main pickler
xpProgram :: PU Program
xpProgram = xpElem "program" $
xpAddFixedAttr "xmlns" "program42" $
xpickle
xpMissingRootElement :: PU Program
xpMissingRootElement = xpickle
instance XmlPickler UnOp where
xpickle = xpPrim
instance XmlPickler Op where
xpickle = xpWrap (toEnum, fromEnum) xpPrim
instance XmlPickler Expr where
xpickle = xpAlt tag ps
where
tag (IntConst _ ) = 0
tag (BoolConst _ ) = 1
tag (Var _ ) = 2
tag (UnExpr _ _ ) = 3
tag (BinExpr _ _ _ ) = 4
ps = [ xpWrap ( IntConst
, \ (IntConst i ) -> i
) $
( xpElem "int" $
xpAttr "value" $
xpickle
)
, xpWrap ( BoolConst
, \ (BoolConst b) -> b
) $
( xpElem "bool" $
xpAttr "value" $
xpWrap (toEnum, fromEnum) xpickle
)
, xpWrap ( Var
, \ (Var n) -> n
) $
( xpElem "var" $
xpAttr "name" $
xpText
)
, xpWrap ( uncurry UnExpr
, \ (UnExpr op e) -> (op, e)
) $
( xpElem "unex" $
xpPair (xpAttr "op" xpickle)
xpickle
)
, xpWrap ( uncurry3 $ BinExpr
, \ (BinExpr op e1 e2) -> (op, e1, e2)
) $
( xpElem "binex" $
xpTriple (xpAttr "op" xpickle)
xpickle
xpickle
)
]
instance XmlPickler Stmt where
xpickle = xpAlt tag ps
where
tag ( Assign _ _ ) = 0
tag ( Stmts _ ) = 1
tag ( If _ _ _ ) = 2
tag ( While _ _ ) = 3
ps = [ xpWrap ( uncurry Assign
, \ (Assign n v) -> (n, v)
) $
( xpElem "assign" $
xpPair (xpAttr "name" xpText)
xpickle
)
, xpWrap ( Stmts
, \ (Stmts sl) -> sl
) $
( xpElem "block" $
xpList xpickle
)
, xpWrap ( uncurry3 If
, \ (If c t e) -> (c, t, e)
) $
( xpElem "if" $
xpTriple xpickle
xpickle
xpickle
)
, xpWrap ( uncurry While
, \ (While c b) -> (c, b)
) $
( xpElem "while" $
xpPair xpickle
xpickle
)
]
-- ------------------------------------------------------------
--
-- example programs
progs :: [Program]
progs = [p0, p1, p2]
p0, p1, p2 :: Program
p0 = Stmts [] -- the empty program
p1 = Stmts
[ Assign i ( UnExpr UMinus ( IntConst (-22) ) )
, Assign j ( IntConst 20 )
, While
( BinExpr Neq ( Var i ) ( IntConst 0 ) )
( Stmts
[ Assign i ( BinExpr Sub ( Var i ) ( IntConst 1 ) )
, Assign j ( BinExpr Add ( Var j ) ( IntConst 1 ) )
, If ( IntConst 0 ) (Stmts []) Nothing
]
)
]
where
i = "i"
j = "j"
p2 = Stmts
[ Assign x (IntConst 6)
, Assign y (IntConst 7)
, Assign p (IntConst 0)
, While
( BinExpr Neq (Var x) (IntConst 0) )
( If ( BinExpr Neq ( BinExpr Mod (Var x) (IntConst 2) ) (IntConst 0) )
( Stmts
[ Assign x ( BinExpr Sub (Var x) (IntConst 1) )
, Assign p ( BinExpr Add (Var p) (Var y) )
]
)
( Just ( Stmts
[ Assign x ( BinExpr Div (Var x) (IntConst 2) )
, Assign y ( BinExpr Mul (Var y) (IntConst 2) )
]
)
)
)
]
where
x = "x"
y = "y"
p = "p"
-- ------------------------------------------------------------
-- |
-- the complete set of test cases
pickleUnpickleTests :: Test
pickleUnpickleTests
= TestLabel "pickle/unpickle tests with example programs" $
TestList $
map mkTests progs
where
mkTests p
= TestList $
[ TestCase $
assertEqual "pickleDoc/unpickleDoc without XML serialisation: " [p] res1
, TestCase $
assertEqual "pickleDoc/unpickleDoc with xshow/xread: " [p] res2
, TestCase $
do
res <- res4
assertEqual "pickle/unpickle with readFromString: " [p] res
, TestCase $
res5 >>=
assertEqual "pickle/unpickle with writeDocument/readDocument: " [p]
, TestCase $
res6 >>=
assertEqual "pickle/unpickle with xpickleDocument/xunpickleDocument: " [p]
, TestCase $
res7 >>=
assertEqual "pickle/unpickle with DTD validation xpickleDocument/xunpickleDocument: " [p]
]
where
res1 :: [Program]
res1 = maybeToList . unpickleDoc xpProgram . pickleDoc xpProgram $ p
res2 :: [Program]
res2 = runLA
( xshow ( arr (pickleDoc xpProgram)
>>>
getChildren
)
>>>
root [] [xread]
>>>
arrL (maybeToList . unpickleDoc xpProgram)
) p
res4 :: IO [Program]
res4 = runX
( constA p
>>>
arr (pickleDoc xpProgram) -- Program => XmlTree
>>>
writeDocumentToString [] -- XmlTree => String
>>>
readFromString [ withValidate no ] -- String => XmlTree
>>>
arrL (maybeToList . unpickleDoc xpProgram) -- XmlTree => Program
)
res5 :: IO [Program] -- the most important case
-- for persistent data storage
-- and message passing
res5 = runX
( constA p -- take the Program value
>>>
arr (pickleDoc xpProgram) -- Program => XmlTree
>>>
writeDocument [ withIndent yes -- XmlTree => formated external XML document
] "pickle.xml"
>>>
readDocument [ withRemoveWS yes -- formated external XML document => XmlTree
, withValidate no
] "pickle.xml"
>>>
arrL (maybeToList . unpickleDoc xpProgram) -- XmlTree => Program
)
res6 :: IO [Program] -- the most important case
-- for persistent data storage
-- and message passing
-- same as res5, but the convenient way
res6 = runX
( constA p -- take the Program value
>>>
xpickleDocument xpProgram
[ withIndent yes -- Program => formated external XML document
] "pickle.xml"
>>>
xunpickleDocument xpProgram
[ withRemoveWS yes -- formated external XML document => Program
, withValidate no
] "pickle.xml"
)
res7 :: IO [Program] -- the most important case
-- for persistent data storage
-- and message passing
-- same as res5, but the convenient way
res7 = runX
( constA p -- take the Program value
>>>
xpickleDocument xpProgram
[ withIndent yes -- Program => formated external XML document
, withSysAttr a_addDTD v_1 -- with inline DTD
] "pickle.xml"
>>>
xunpickleDocument xpProgram
[ withRemoveWS yes -- formated external XML document => Program
, withValidate yes
] "pickle.xml"
)
allTests :: Test
allTests
= TestList
[ pickleUnpickleTests
-- , pickleXshowTests
]
main :: IO ()
main
= do
c <- runTestTT allTests
putStrLn $ show c
let errs = errors c
fails = failures c
exitWith (codeGet errs fails)
codeGet :: Int -> Int -> ExitCode
codeGet errs fails
| fails > 0 = ExitFailure 2
| errs > 0 = ExitFailure 1
| otherwise = ExitSuccess
-- ----------------------------------------------------------
|
