hledger/hledger-lib/Hledger/Utils.hs
2015-02-09 17:42:51 +00:00

461 lines
16 KiB
Haskell

{-# LANGUAGE FlexibleContexts #-}
{-|
Standard imports and utilities which are useful everywhere, or needed low
in the module hierarchy. This is the bottom of hledger's module graph.
-}
module Hledger.Utils (---- provide these frequently used modules - or not, for clearer api:
-- module Control.Monad,
-- module Data.List,
-- module Data.Maybe,
-- module Data.Time.Calendar,
-- module Data.Time.Clock,
-- module Data.Time.LocalTime,
-- module Data.Tree,
-- module Text.RegexPR,
-- module Test.HUnit,
-- module Text.Printf,
---- all of this one:
module Hledger.Utils,
module Hledger.Utils.Debug,
module Hledger.Utils.Regex,
-- Debug.Trace.trace,
-- module Data.PPrint,
-- module Hledger.Utils.UTF8IOCompat
SystemString,fromSystemString,toSystemString,error',userError',
-- the rest need to be done in each module I think
)
where
import Control.Monad (liftM)
import Control.Monad.Error (MonadIO)
import Control.Monad.IO.Class (liftIO)
import Data.Char
import Data.List
import qualified Data.Map as M
-- import Data.Maybe
-- import Data.PPrint
import Data.Time.Clock
import Data.Time.LocalTime
import Data.Tree
import System.Directory (getHomeDirectory)
import System.FilePath((</>), isRelative)
import System.IO
import Test.HUnit
import Text.Parsec
import Text.Printf
-- import qualified Data.Map as Map
import Hledger.Utils.Debug
import Hledger.Utils.Regex
-- import Prelude hiding (readFile,writeFile,appendFile,getContents,putStr,putStrLn)
-- import Hledger.Utils.UTF8IOCompat (readFile,writeFile,appendFile,getContents,putStr,putStrLn)
import Hledger.Utils.UTF8IOCompat (SystemString,fromSystemString,toSystemString,error',userError')
-- strings
lowercase, uppercase :: String -> String
lowercase = map toLower
uppercase = map toUpper
-- | Remove leading and trailing whitespace.
strip :: String -> String
strip = lstrip . rstrip
-- | Remove leading whitespace.
lstrip :: String -> String
lstrip = dropWhile (`elem` " \t") :: String -> String -- XXX isSpace ?
-- | Remove trailing whitespace.
rstrip :: String -> String
rstrip = reverse . lstrip . reverse
-- | Remove trailing newlines/carriage returns.
chomp :: String -> String
chomp = reverse . dropWhile (`elem` "\r\n") . reverse
stripbrackets :: String -> String
stripbrackets = dropWhile (`elem` "([") . reverse . dropWhile (`elem` "])") . reverse :: String -> String
elideLeft :: Int -> String -> String
elideLeft width s =
if length s > width then ".." ++ reverse (take (width - 2) $ reverse s) else s
elideRight :: Int -> String -> String
elideRight width s =
if length s > width then take (width - 2) s ++ ".." else s
underline :: String -> String
underline s = s' ++ replicate (length s) '-' ++ "\n"
where s'
| last s == '\n' = s
| otherwise = s ++ "\n"
-- | Wrap a string in double quotes, and \-prefix any embedded single
-- quotes, if it contains whitespace and is not already single- or
-- double-quoted.
quoteIfSpaced :: String -> String
quoteIfSpaced s | isSingleQuoted s || isDoubleQuoted s = s
| not $ any (`elem` s) whitespacechars = s
| otherwise = "'"++escapeSingleQuotes s++"'"
-- | Double-quote this string if it contains whitespace, single quotes
-- or double-quotes, escaping the quotes as needed.
quoteIfNeeded :: String -> String
quoteIfNeeded s | any (`elem` s) (quotechars++whitespacechars) = "\"" ++ escapeDoubleQuotes s ++ "\""
| otherwise = s
-- | Single-quote this string if it contains whitespace or double-quotes.
-- No good for strings containing single quotes.
singleQuoteIfNeeded :: String -> String
singleQuoteIfNeeded s | any (`elem` s) whitespacechars = "'"++s++"'"
| otherwise = s
quotechars, whitespacechars :: [Char]
quotechars = "'\""
whitespacechars = " \t\n\r"
escapeDoubleQuotes :: String -> String
escapeDoubleQuotes = regexReplace "\"" "\""
escapeSingleQuotes :: String -> String
escapeSingleQuotes = regexReplace "'" "\'"
escapeQuotes :: String -> String
escapeQuotes = regexReplace "([\"'])" "\\1"
-- | Quote-aware version of words - don't split on spaces which are inside quotes.
-- NB correctly handles "a'b" but not "''a''". Can raise an error if parsing fails.
words' :: String -> [String]
words' "" = []
words' s = map stripquotes $ fromparse $ parsewith p s
where
p = do ss <- (singleQuotedPattern <|> doubleQuotedPattern <|> pattern) `sepBy` many1 spacenonewline
-- eof
return ss
pattern = many (noneOf whitespacechars)
singleQuotedPattern = between (char '\'') (char '\'') (many $ noneOf "'")
doubleQuotedPattern = between (char '"') (char '"') (many $ noneOf "\"")
-- | Quote-aware version of unwords - single-quote strings which contain whitespace
unwords' :: [String] -> String
unwords' = unwords . map quoteIfNeeded
-- | Strip one matching pair of single or double quotes on the ends of a string.
stripquotes :: String -> String
stripquotes s = if isSingleQuoted s || isDoubleQuoted s then init $ tail s else s
isSingleQuoted s@(_:_:_) = head s == '\'' && last s == '\''
isSingleQuoted _ = False
isDoubleQuoted s@(_:_:_) = head s == '"' && last s == '"'
isDoubleQuoted _ = False
unbracket :: String -> String
unbracket s
| (head s == '[' && last s == ']') || (head s == '(' && last s == ')') = init $ tail s
| otherwise = s
-- | Join multi-line strings as side-by-side rectangular strings of the same height, top-padded.
concatTopPadded :: [String] -> String
concatTopPadded strs = intercalate "\n" $ map concat $ transpose padded
where
lss = map lines strs
h = maximum $ map length lss
ypad ls = replicate (difforzero h (length ls)) "" ++ ls
xpad ls = map (padleft w) ls where w | null ls = 0
| otherwise = maximum $ map length ls
padded = map (xpad . ypad) lss
-- | Join multi-line strings as side-by-side rectangular strings of the same height, bottom-padded.
concatBottomPadded :: [String] -> String
concatBottomPadded strs = intercalate "\n" $ map concat $ transpose padded
where
lss = map lines strs
h = maximum $ map length lss
ypad ls = ls ++ replicate (difforzero h (length ls)) ""
xpad ls = map (padright w) ls where w | null ls = 0
| otherwise = maximum $ map length ls
padded = map (xpad . ypad) lss
-- | Compose strings vertically and right-aligned.
vConcatRightAligned :: [String] -> String
vConcatRightAligned ss = intercalate "\n" $ map showfixedwidth ss
where
showfixedwidth = printf (printf "%%%ds" width)
width = maximum $ map length ss
-- | Convert a multi-line string to a rectangular string top-padded to the specified height.
padtop :: Int -> String -> String
padtop h s = intercalate "\n" xpadded
where
ls = lines s
sh = length ls
sw | null ls = 0
| otherwise = maximum $ map length ls
ypadded = replicate (difforzero h sh) "" ++ ls
xpadded = map (padleft sw) ypadded
-- | Convert a multi-line string to a rectangular string bottom-padded to the specified height.
padbottom :: Int -> String -> String
padbottom h s = intercalate "\n" xpadded
where
ls = lines s
sh = length ls
sw | null ls = 0
| otherwise = maximum $ map length ls
ypadded = ls ++ replicate (difforzero h sh) ""
xpadded = map (padleft sw) ypadded
-- | Convert a multi-line string to a rectangular string left-padded to the specified width.
padleft :: Int -> String -> String
padleft w "" = concat $ replicate w " "
padleft w s = intercalate "\n" $ map (printf (printf "%%%ds" w)) $ lines s
-- | Convert a multi-line string to a rectangular string right-padded to the specified width.
padright :: Int -> String -> String
padright w "" = concat $ replicate w " "
padright w s = intercalate "\n" $ map (printf (printf "%%-%ds" w)) $ lines s
-- | Clip a multi-line string to the specified width and height from the top left.
cliptopleft :: Int -> Int -> String -> String
cliptopleft w h = intercalate "\n" . take h . map (take w) . lines
-- | Clip and pad a multi-line string to fill the specified width and height.
fitto :: Int -> Int -> String -> String
fitto w h s = intercalate "\n" $ take h $ rows ++ repeat blankline
where
rows = map (fit w) $ lines s
fit w = take w . (++ repeat ' ')
blankline = replicate w ' '
-- tuples
first3 (x,_,_) = x
second3 (_,x,_) = x
third3 (_,_,x) = x
first4 (x,_,_,_) = x
second4 (_,x,_,_) = x
third4 (_,_,x,_) = x
fourth4 (_,_,_,x) = x
first5 (x,_,_,_,_) = x
second5 (_,x,_,_,_) = x
third5 (_,_,x,_,_) = x
fourth5 (_,_,_,x,_) = x
fifth5 (_,_,_,_,x) = x
-- math
difforzero :: (Num a, Ord a) => a -> a -> a
difforzero a b = maximum [(a - b), 0]
-- lists
splitAtElement :: Eq a => a -> [a] -> [[a]]
splitAtElement x l =
case l of
[] -> []
e:es | e==x -> split es
es -> split es
where
split es = let (first,rest) = break (x==) es
in first : splitAtElement x rest
-- trees
-- standard tree helpers
root = rootLabel
subs = subForest
branches = subForest
-- | List just the leaf nodes of a tree
leaves :: Tree a -> [a]
leaves (Node v []) = [v]
leaves (Node _ branches) = concatMap leaves branches
-- | get the sub-tree rooted at the first (left-most, depth-first) occurrence
-- of the specified node value
subtreeat :: Eq a => a -> Tree a -> Maybe (Tree a)
subtreeat v t
| root t == v = Just t
| otherwise = subtreeinforest v $ subs t
-- | get the sub-tree for the specified node value in the first tree in
-- forest in which it occurs.
subtreeinforest :: Eq a => a -> [Tree a] -> Maybe (Tree a)
subtreeinforest _ [] = Nothing
subtreeinforest v (t:ts) = case (subtreeat v t) of
Just t' -> Just t'
Nothing -> subtreeinforest v ts
-- | remove all nodes past a certain depth
treeprune :: Int -> Tree a -> Tree a
treeprune 0 t = Node (root t) []
treeprune d t = Node (root t) (map (treeprune $ d-1) $ branches t)
-- | apply f to all tree nodes
treemap :: (a -> b) -> Tree a -> Tree b
treemap f t = Node (f $ root t) (map (treemap f) $ branches t)
-- | remove all subtrees whose nodes do not fulfill predicate
treefilter :: (a -> Bool) -> Tree a -> Tree a
treefilter f t = Node
(root t)
(map (treefilter f) $ filter (treeany f) $ branches t)
-- | is predicate true in any node of tree ?
treeany :: (a -> Bool) -> Tree a -> Bool
treeany f t = f (root t) || any (treeany f) (branches t)
-- treedrop -- remove the leaves which do fulfill predicate.
-- treedropall -- do this repeatedly.
-- | show a compact ascii representation of a tree
showtree :: Show a => Tree a -> String
showtree = unlines . filter (regexMatches "[^ \\|]") . lines . drawTree . treemap show
-- | show a compact ascii representation of a forest
showforest :: Show a => Forest a -> String
showforest = concatMap showtree
-- | An efficient-to-build tree suggested by Cale Gibbard, probably
-- better than accountNameTreeFrom.
newtype FastTree a = T (M.Map a (FastTree a))
deriving (Show, Eq, Ord)
emptyTree = T M.empty
mergeTrees :: (Ord a) => FastTree a -> FastTree a -> FastTree a
mergeTrees (T m) (T m') = T (M.unionWith mergeTrees m m')
treeFromPath :: [a] -> FastTree a
treeFromPath [] = T M.empty
treeFromPath (x:xs) = T (M.singleton x (treeFromPath xs))
treeFromPaths :: (Ord a) => [[a]] -> FastTree a
treeFromPaths = foldl' mergeTrees emptyTree . map treeFromPath
-- parsing
-- | Backtracking choice, use this when alternatives share a prefix.
-- Consumes no input if all choices fail.
choice' :: Stream s m t => [ParsecT s u m a] -> ParsecT s u m a
choice' = choice . map Text.Parsec.try
parsewith :: Parsec [Char] () a -> String -> Either ParseError a
parsewith p = runParser p () ""
parseWithCtx :: Stream s m t => u -> ParsecT s u m a -> s -> m (Either ParseError a)
parseWithCtx ctx p = runParserT p ctx ""
fromparse :: Either ParseError a -> a
fromparse = either parseerror id
parseerror :: ParseError -> a
parseerror e = error' $ showParseError e
showParseError :: ParseError -> String
showParseError e = "parse error at " ++ show e
showDateParseError :: ParseError -> String
showDateParseError e = printf "date parse error (%s)" (intercalate ", " $ tail $ lines $ show e)
nonspace :: (Stream [Char] m Char) => ParsecT [Char] st m Char
nonspace = satisfy (not . isSpace)
spacenonewline :: (Stream [Char] m Char) => ParsecT [Char] st m Char
spacenonewline = satisfy (`elem` " \v\f\t")
restofline :: (Stream [Char] m Char) => ParsecT [Char] st m String
restofline = anyChar `manyTill` newline
eolof :: (Stream [Char] m Char) => ParsecT [Char] st m ()
eolof = (newline >> return ()) <|> eof
-- time
getCurrentLocalTime :: IO LocalTime
getCurrentLocalTime = do
t <- getCurrentTime
tz <- getCurrentTimeZone
return $ utcToLocalTime tz t
-- testing
-- | Get a Test's label, or the empty string.
testName :: Test -> String
testName (TestLabel n _) = n
testName _ = ""
-- | Flatten a Test containing TestLists into a list of single tests.
flattenTests :: Test -> [Test]
flattenTests (TestLabel _ t@(TestList _)) = flattenTests t
flattenTests (TestList ts) = concatMap flattenTests ts
flattenTests t = [t]
-- | Filter TestLists in a Test, recursively, preserving the structure.
filterTests :: (Test -> Bool) -> Test -> Test
filterTests p (TestLabel l ts) = TestLabel l (filterTests p ts)
filterTests p (TestList ts) = TestList $ filter (any p . flattenTests) $ map (filterTests p) ts
filterTests _ t = t
-- | Simple way to assert something is some expected value, with no label.
is :: (Eq a, Show a) => a -> a -> Assertion
a `is` e = assertEqual "" e a
-- | Assert a parse result is successful, printing the parse error on failure.
assertParse :: (Either ParseError a) -> Assertion
assertParse parse = either (assertFailure.show) (const (return ())) parse
-- | Assert a parse result is successful, printing the parse error on failure.
assertParseFailure :: (Either ParseError a) -> Assertion
assertParseFailure parse = either (const $ return ()) (const $ assertFailure "parse should not have succeeded") parse
-- | Assert a parse result is some expected value, printing the parse error on failure.
assertParseEqual :: (Show a, Eq a) => (Either ParseError a) -> a -> Assertion
assertParseEqual parse expected = either (assertFailure.show) (`is` expected) parse
printParseError :: (Show a) => a -> IO ()
printParseError e = do putStr "parse error at "; print e
-- misc
isLeft :: Either a b -> Bool
isLeft (Left _) = True
isLeft _ = False
isRight :: Either a b -> Bool
isRight = not . isLeft
-- | Apply a function the specified number of times. Possibly uses O(n) stack ?
applyN :: Int -> (a -> a) -> a -> a
applyN n f = (!! n) . iterate f
-- | Convert a possibly relative, possibly tilde-containing file path to an absolute one,
-- given the current directory. ~username is not supported. Leave "-" unchanged.
expandPath :: MonadIO m => FilePath -> FilePath -> m FilePath -- general type sig for use in reader parsers
expandPath _ "-" = return "-"
expandPath curdir p = (if isRelative p then (curdir </>) else id) `liftM` expandPath' p
where
expandPath' ('~':'/':p) = liftIO $ (</> p) `fmap` getHomeDirectory
expandPath' ('~':'\\':p) = liftIO $ (</> p) `fmap` getHomeDirectory
expandPath' ('~':_) = error' "~USERNAME in paths is not supported"
expandPath' p = return p
firstJust ms = case dropWhile (==Nothing) ms of
[] -> Nothing
(md:_) -> md
-- | Read a file in universal newline mode, handling whatever newline convention it may contain.
readFile' :: FilePath -> IO String
readFile' name = do
h <- openFile name ReadMode
hSetNewlineMode h universalNewlineMode
hGetContents h