hledger/hledger-lib/Hledger/Data/StringFormat.hs
Simon Michael c80c72d7cd dev: lib, cli, bin: enable/fix name shadowing warnings
And a few other cleanups.
2022-08-23 12:16:15 +01:00

193 lines
9.3 KiB
Haskell

-- | Parse format strings provided by --format, with awareness of
-- hledger's report item fields. The formats are used by
-- report-specific renderers like renderBalanceReportItem.
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE TypeFamilies #-}
module Hledger.Data.StringFormat (
parseStringFormat
, defaultStringFormatStyle
, StringFormat(..)
, StringFormatComponent(..)
, ReportItemField(..)
, defaultBalanceLineFormat
, tests_StringFormat
) where
import Numeric (readDec)
import Data.Char (isPrint)
import Data.Default (Default(..))
import Data.Maybe (isJust)
import Data.Text (Text)
import qualified Data.Text as T
import Text.Megaparsec
import Text.Megaparsec.Char (char, digitChar, string)
import Hledger.Utils.Parse (SimpleTextParser)
import Hledger.Utils.Text (formatText)
import Hledger.Utils.Test
-- | A format specification/template to use when rendering a report line item as text.
--
-- A format is a sequence of components; each is either a literal
-- string, or a hledger report item field with specified width and
-- justification whose value will be interpolated at render time.
--
-- A component's value may be a multi-line string (or a
-- multi-commodity amount), in which case the final string will be
-- either single-line or a top or bottom-aligned multi-line string
-- depending on the StringFormat variant used.
--
-- Currently this is only used in the balance command's single-column
-- mode, which provides a limited StringFormat renderer.
--
data StringFormat =
OneLine [StringFormatComponent] -- ^ multi-line values will be rendered on one line, comma-separated
| TopAligned [StringFormatComponent] -- ^ values will be top-aligned (and bottom-padded to the same height)
| BottomAligned [StringFormatComponent] -- ^ values will be bottom-aligned (and top-padded)
deriving (Show, Eq)
data StringFormatComponent =
FormatLiteral Text -- ^ Literal text to be rendered as-is
| FormatField Bool
(Maybe Int)
(Maybe Int)
ReportItemField -- ^ A data field to be formatted and interpolated. Parameters:
--
-- - Left justify ? Right justified if false
-- - Minimum width ? Will be space-padded if narrower than this
-- - Maximum width ? Will be clipped if wider than this
-- - Which of the standard hledger report item fields to interpolate
deriving (Show, Eq)
-- | An id identifying which report item field to interpolate. These
-- are drawn from several hledger report types, so are not all
-- applicable for a given report.
data ReportItemField =
AccountField -- ^ A posting or balance report item's account name
| DefaultDateField -- ^ A posting or register or entry report item's date
| DescriptionField -- ^ A posting or register or entry report item's description
| TotalField -- ^ A balance or posting report item's balance or running total.
-- Always rendered right-justified.
| DepthSpacerField -- ^ A balance report item's indent level (which may be different from the account name depth).
-- Rendered as this number of spaces, multiplied by the minimum width spec if any.
| FieldNo Int -- ^ A report item's nth field. May be unimplemented.
deriving (Show, Eq)
instance Default StringFormat where def = defaultBalanceLineFormat
-- | Default line format for balance report: "%20(total) %2(depth_spacer)%-(account)"
defaultBalanceLineFormat :: StringFormat
defaultBalanceLineFormat = BottomAligned [
FormatField False (Just 20) Nothing TotalField
, FormatLiteral " "
, FormatField True (Just 2) Nothing DepthSpacerField
, FormatField True Nothing Nothing AccountField
]
----------------------------------------------------------------------
-- renderStringFormat :: StringFormat -> Map String String -> String
-- renderStringFormat fmt params =
----------------------------------------------------------------------
-- | Parse a string format specification, or return a parse error.
parseStringFormat :: Text -> Either String StringFormat
parseStringFormat input = case (runParser (stringformatp <* eof) "(unknown)") input of
Left y -> Left $ show y
Right x -> Right x
defaultStringFormatStyle = BottomAligned
stringformatp :: SimpleTextParser StringFormat
stringformatp = do
alignspec <- optional (try $ char '%' >> oneOf ("^_,"::String))
let constructor =
case alignspec of
Just '^' -> TopAligned
Just '_' -> BottomAligned
Just ',' -> OneLine
_ -> defaultStringFormatStyle
constructor <$> many componentp
componentp :: SimpleTextParser StringFormatComponent
componentp = formatliteralp <|> formatfieldp
formatliteralp :: SimpleTextParser StringFormatComponent
formatliteralp = do
s <- T.pack <$> some c
return $ FormatLiteral s
where
isPrintableButNotPercentage x = isPrint x && x /= '%'
c = (satisfy isPrintableButNotPercentage <?> "printable character")
<|> try (string "%%" >> return '%')
formatfieldp :: SimpleTextParser StringFormatComponent
formatfieldp = do
char '%'
leftJustified <- optional (char '-')
minWidth <- optional (some $ digitChar)
maxWidth <- optional (do char '.'; some $ digitChar) -- TODO: Can this be (char '1') *> (some digitChar)
char '('
f <- fieldp
char ')'
return $ FormatField (isJust leftJustified) (parseDec minWidth <|> Just 0) (parseDec maxWidth) f
where
parseDec s = case s of
Just text -> Just m where ((m,_):_) = readDec text
_ -> Nothing
fieldp :: SimpleTextParser ReportItemField
fieldp = do
try (string "account" >> return AccountField)
<|> try (string "depth_spacer" >> return DepthSpacerField)
<|> try (string "date" >> return DescriptionField)
<|> try (string "description" >> return DescriptionField)
<|> try (string "total" >> return TotalField)
<|> try ((FieldNo . read) <$> some digitChar)
----------------------------------------------------------------------
formatStringTester fs value expected = actual @?= expected
where
actual = case fs of
FormatLiteral l -> formatText False Nothing Nothing l
FormatField leftJustify mn mx _ -> formatText leftJustify mn mx value
tests_StringFormat = testGroup "StringFormat" [
testCase "formatStringHelper" $ do
formatStringTester (FormatLiteral " ") "" " "
formatStringTester (FormatField False Nothing Nothing DescriptionField) "description" "description"
formatStringTester (FormatField False (Just 20) Nothing DescriptionField) "description" " description"
formatStringTester (FormatField False Nothing (Just 20) DescriptionField) "description" "description"
formatStringTester (FormatField True Nothing (Just 20) DescriptionField) "description" "description"
formatStringTester (FormatField True (Just 20) Nothing DescriptionField) "description" "description "
formatStringTester (FormatField True (Just 20) (Just 20) DescriptionField) "description" "description "
formatStringTester (FormatField True Nothing (Just 3) DescriptionField) "description" "des"
,let s `gives` expected = testCase s $ parseStringFormat (T.pack s) @?= Right expected
in testGroup "parseStringFormat" [
"" `gives` (defaultStringFormatStyle [])
, "D" `gives` (defaultStringFormatStyle [FormatLiteral "D"])
, "%(date)" `gives` (defaultStringFormatStyle [FormatField False (Just 0) Nothing DescriptionField])
, "%(total)" `gives` (defaultStringFormatStyle [FormatField False (Just 0) Nothing TotalField])
-- TODO
-- , "^%(total)" `gives` (TopAligned [FormatField False Nothing Nothing TotalField])
-- , "_%(total)" `gives` (BottomAligned [FormatField False Nothing Nothing TotalField])
-- , ",%(total)" `gives` (OneLine [FormatField False Nothing Nothing TotalField])
, "Hello %(date)!" `gives` (defaultStringFormatStyle [FormatLiteral "Hello ", FormatField False (Just 0) Nothing DescriptionField, FormatLiteral "!"])
, "%-(date)" `gives` (defaultStringFormatStyle [FormatField True (Just 0) Nothing DescriptionField])
, "%20(date)" `gives` (defaultStringFormatStyle [FormatField False (Just 20) Nothing DescriptionField])
, "%.10(date)" `gives` (defaultStringFormatStyle [FormatField False (Just 0) (Just 10) DescriptionField])
, "%20.10(date)" `gives` (defaultStringFormatStyle [FormatField False (Just 20) (Just 10) DescriptionField])
, "%20(account) %.10(total)" `gives` (defaultStringFormatStyle [FormatField False (Just 20) Nothing AccountField
,FormatLiteral " "
,FormatField False (Just 0) (Just 10) TotalField
])
, testCase "newline not parsed" $ assertLeft $ parseStringFormat "\n"
]
]