3fecebd5ba
This is needed to support addToken_ workaround before the fix.
Before the fix, an extra space was needed in the selector like this
example:
addToken "form.foo "
With the fix adding the missing space, code already adding a space
will end up with two spaces between the scope selector and the input one :
form.foo input[name=token_]
106 lines
3.2 KiB
Haskell
106 lines
3.2 KiB
Haskell
{-# LANGUAGE OverloadedStrings #-}
|
|
-- | Parsing CSS selectors into queries.
|
|
module Yesod.Test.CssQuery
|
|
( SelectorGroup (..)
|
|
, Selector (..)
|
|
, parseQuery
|
|
) where
|
|
|
|
import Prelude hiding (takeWhile)
|
|
import Data.Text (Text)
|
|
import Data.Attoparsec.Text
|
|
import Control.Applicative
|
|
import Data.Char
|
|
|
|
import qualified Data.Text as T
|
|
|
|
data SelectorGroup
|
|
= DirectChildren [Selector]
|
|
| DeepChildren [Selector]
|
|
deriving (Show, Eq)
|
|
|
|
data Selector
|
|
= ById Text
|
|
| ByClass Text
|
|
| ByTagName Text
|
|
| ByAttrExists Text
|
|
| ByAttrEquals Text Text
|
|
| ByAttrContains Text Text
|
|
| ByAttrStarts Text Text
|
|
| ByAttrEnds Text Text
|
|
deriving (Show, Eq)
|
|
|
|
|
|
-- The official syntax specification for CSS2 can be found here:
|
|
-- http://www.w3.org/TR/CSS2/syndata.html
|
|
-- but that spec is tricky to fully support. Instead we do the minimal and we
|
|
-- can extend it as needed.
|
|
|
|
|
|
-- | Parses a query into an intermediate format which is easy to feed to HXT
|
|
--
|
|
-- * The top-level lists represent the top level comma separated queries.
|
|
--
|
|
-- * SelectorGroup is a group of qualifiers which are separated
|
|
-- with spaces or > like these three: /table.main.odd tr.even > td.big/
|
|
--
|
|
-- * A SelectorGroup as a list of Selector items, following the above example
|
|
-- the selectors in the group are: /table/, /.main/ and /.odd/
|
|
parseQuery :: Text -> Either String [[SelectorGroup]]
|
|
parseQuery = parseOnly cssQuery
|
|
|
|
-- Below this line is the Parsec parser for css queries.
|
|
cssQuery :: Parser [[SelectorGroup]]
|
|
cssQuery = many (char ' ') >> sepBy rules (char ',' >> many (char ' '))
|
|
|
|
rules :: Parser [SelectorGroup]
|
|
rules = many $ directChildren <|> deepChildren
|
|
|
|
directChildren :: Parser SelectorGroup
|
|
directChildren =
|
|
string "> " >> (many (char ' ')) >> DirectChildren <$> pOptionalTrailingSpace parseSelectors
|
|
|
|
deepChildren :: Parser SelectorGroup
|
|
deepChildren = pOptionalTrailingSpace $ DeepChildren <$> parseSelectors
|
|
|
|
parseSelectors :: Parser [Selector]
|
|
parseSelectors = many1 $
|
|
parseId <|> parseClass <|> parseTag <|> parseAttr
|
|
|
|
parseId :: Parser Selector
|
|
parseId = char '#' >> ById <$> pIdent
|
|
|
|
parseClass :: Parser Selector
|
|
parseClass = char '.' >> ByClass <$> pIdent
|
|
|
|
parseTag :: Parser Selector
|
|
parseTag = ByTagName <$> pIdent
|
|
|
|
parseAttr :: Parser Selector
|
|
parseAttr = pSquare $ choice
|
|
[ ByAttrEquals <$> pIdent <*> (string "=" *> pAttrValue)
|
|
, ByAttrContains <$> pIdent <*> (string "*=" *> pAttrValue)
|
|
, ByAttrStarts <$> pIdent <*> (string "^=" *> pAttrValue)
|
|
, ByAttrEnds <$> pIdent <*> (string "$=" *> pAttrValue)
|
|
, ByAttrExists <$> pIdent
|
|
]
|
|
|
|
-- | pIdent : Parse an identifier (not yet supporting escapes and unicode as
|
|
-- part of the identifier). Basically the regex: [-]?[_a-zA-Z][_a-zA-Z0-9]*
|
|
pIdent :: Parser Text
|
|
pIdent = do
|
|
leadingMinus <- string "-" <|> pure ""
|
|
nmstart <- T.singleton <$> satisfy (\c -> isAlpha c || c == '_')
|
|
nmchar <- takeWhile (\c -> isAlphaNum c || c == '_' || c == '-')
|
|
return $ T.concat [ leadingMinus, nmstart, nmchar ]
|
|
|
|
|
|
pAttrValue :: Parser Text
|
|
pAttrValue = takeWhile (/= ']')
|
|
|
|
pSquare :: Parser a -> Parser a
|
|
pSquare p = char '[' *> p <* char ']'
|
|
|
|
pOptionalTrailingSpace :: Parser a -> Parser a
|
|
pOptionalTrailingSpace p = p <* many (char ' ')
|