fix number parser in duration

Author: safareli

src/Data/Formatter/Interval.purs

@@ -5,39 +5,49 @@ module Data.Formatter.Interval
 
 import Prelude
 import Data.Interval as I
+import Math as Math
 import Text.Parsing.Parser as P
 import Text.Parsing.Parser.Combinators as PC
 import Text.Parsing.Parser.String as PS
 import Control.Alt ((<|>))
-import Data.Array (length, some)
+import Data.Array (some)
+import Data.Function (on)
 import Data.Formatter.Internal (digit, foldDigits)
-import Data.Int (toNumber)
+import Data.Int (toNumber, floor)
 import Data.Monoid (mempty)
 
 
-nums ∷ P.Parser String Int
-nums = foldDigits <$> some digit
+numOfDigits ∷ Int → Int
+numOfDigits 0 = 0
+numOfDigits n = 1 + (floor $ log10 $ toNumber n)
 
--- TODO try to use unformatNumberParser here
-number ∷ P.Parser String Number
-number = do
-  whole ← nums
-  _ ← (PC.try $ PS.string ".") <|> (PC.try $ PS.string ",") <|> pure ""
-  restdigits ← PC.try (some digit) <|> pure [0]
-  let rest = foldDigits restdigits
-  pure $ if rest == 0 then toNumber whole else toNumber whole + ((toNumber rest) / (toNumber $ length restdigits))
+log10 ∷ Number → Number
+log10 n = Math.log10e * Math.log n
+
+integer ∷ P.Parser String Int
+integer = some digit <#> foldDigits
 
+pow :: Int -> Int -> Number
+pow = Math.pow `on` toNumber
 
+fractional ∷ P.Parser String Number
+fractional = integer <#> case _ of
+  0 ->  0.0
+  n -> (toNumber n) / (pow 10 $ numOfDigits n)
+
+number ∷ P.Parser String Number
+number = (+)
+  <$> (integer <#> toNumber)
+  <*> (PC.option 0.0 $ PC.try $ PS.oneOf ['.', ','] *> fractional)
 
 component ∷ String → P.Parser String Number
 component designator = number <* PS.string designator
 
 tryOr :: ∀ a. a → P.Parser String a → P.Parser String a
 tryOr a p = PC.option a $ PC.try p
 
-parseDuration :: P.Parser String (I.Duration)
--- parseDuration = PS.string "P" *> weekDuration
-parseDuration = PS.string "P" *> (weekDuration <|> fullDuration)-- <* PS.eof
+parseDuration :: P.Parser String I.Duration
+parseDuration = PS.string "P" *> (weekDuration <|> fullDuration) <* PS.eof
   where
     weekDuration :: P.Parser String I.Duration
     weekDuration = PC.try $ I.week <$> component "W"

src/Data/Formatter/Number.purs

@@ -11,8 +11,6 @@ module Data.Formatter.Number
   , formatNumber
   , formatOrShowNumber
   , unformatNumber
-  -- TODO move to internal or add doc
-  , unformatNumberParser
   ) where
 
 import Prelude
@@ -22,7 +20,7 @@ import Data.Array as Arr
 import Data.Array (many, some)
 import Data.Maybe (Maybe(..), fromMaybe, isJust)
 import Data.Traversable (for)
-import Data.Either (Either(..), either)
+import Data.Either (Either, either)
 import Data.Int as Int
 import Data.String as Str
 
@@ -219,11 +217,6 @@ unformatNumber ∷ String → String → Either String Number
 unformatNumber pattern str =
   parseFormatString pattern >>= flip unformat str
 
-unformatNumberParser ∷ String → P.Parser String Number
-unformatNumberParser pattern = case P.runParser pattern formatParser of
-    Left e → P.fail $ P.parseErrorMessage e
-    Right p → unformatParser p
-
 -- Supposed to be used in chaining, because after calling format number there is no
 -- good way to extract number back to show.
 formatOrShowNumber ∷ String → Number → String

test/src/Main.purs

@@ -173,7 +173,7 @@ timeInterval = do
   log "- Data.Formatter.Interval.parseDuration"
   assertParserRes (P.runParser "P1W" FI.parseDuration) (Right $ I.day 7.0)
   assertParserRes (P.runParser "P1.0W" FI.parseDuration) (Right $ I.day 7.0)
-  assertParserRes (P.runParser "P1.0D" FI.parseDuration) (Right $ I.day 1.0)
+  assertParserRes (P.runParser "P1.9748600D" FI.parseDuration) (Right $ I.day 1.97486)
   assertParserRes (P.runParser "P1DT1H1M1S" FI.parseDuration) (Right $ I.day 1.0 <> I.hours 1.0 <> I.minutes 1.0 <> I.seconds 1.0)
 timeTest :: forall e. Tests e Unit
 timeTest = do