dhall-1.30.0: src/Dhall/Pretty/Internal.hs
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
{-# OPTIONS_GHC -Wall #-}
{-| This module provides internal pretty-printing utilities which are used by
other modules but are not part of the public facing API
-}
module Dhall.Pretty.Internal (
Ann(..)
, annToAnsiStyle
, prettyExpr
, prettySrcExpr
, CharacterSet(..)
, prettyCharacterSet
, prettyVar
, pretty_
, escapeText_
, escapeEnvironmentVariable
, prettyEnvironmentVariable
, prettyConst
, escapeLabel
, prettyLabel
, prettyAnyLabel
, prettyLabels
, prettyNatural
, prettyNumber
, prettyInt
, prettyDouble
, prettyToStrictText
, prettyToString
, layout
, layoutOpts
, docToStrictText
, builtin
, keyword
, literal
, operator
, colon
, comma
, dot
, equals
, forall
, label
, lambda
, langle
, lbrace
, lbracket
, lparen
, pipe
, rangle
, rarrow
, rbrace
, rbracket
, rparen
) where
import Data.Foldable
import Data.List.NonEmpty (NonEmpty)
import Data.Monoid ((<>))
import Data.Text (Text)
import Data.Text.Prettyprint.Doc (Doc, Pretty, space)
import Dhall.Map (Map)
import Dhall.Set (Set)
import Dhall.Src (Src(..))
import Dhall.Syntax
import Numeric.Natural (Natural)
import Prelude hiding (succ)
import qualified Data.Text.Prettyprint.Doc.Render.Terminal as Terminal
import qualified Data.Char
import qualified Data.HashSet
import qualified Data.List
import qualified Data.List.NonEmpty as NonEmpty
import qualified Data.Set
import qualified Data.Text as Text
import qualified Data.Text.Prettyprint.Doc as Pretty
import qualified Data.Text.Prettyprint.Doc.Render.Text as Pretty
import qualified Data.Text.Prettyprint.Doc.Render.String as Pretty
import qualified Dhall.Map as Map
import qualified Dhall.Set
{-| Annotation type used to tag elements in a pretty-printed document for
syntax highlighting purposes
-}
data Ann
= Keyword -- ^ Used for syntactic keywords
| Syntax -- ^ Syntax punctuation such as commas, parenthesis, and braces
| Label -- ^ Record labels
| Literal -- ^ Literals such as integers and strings
| Builtin -- ^ Builtin types and values
| Operator -- ^ Operators
deriving Show
{-| Convert annotations to their corresponding color for syntax highlighting
purposes
-}
annToAnsiStyle :: Ann -> Terminal.AnsiStyle
annToAnsiStyle Keyword = Terminal.bold <> Terminal.colorDull Terminal.Green
annToAnsiStyle Syntax = Terminal.bold <> Terminal.colorDull Terminal.Green
annToAnsiStyle Label = mempty
annToAnsiStyle Literal = Terminal.colorDull Terminal.Magenta
annToAnsiStyle Builtin = Terminal.underlined
annToAnsiStyle Operator = Terminal.bold <> Terminal.colorDull Terminal.Green
-- | This type determines whether to render code as `ASCII` or `Unicode`
data CharacterSet = ASCII | Unicode deriving Show
-- | Pretty print an expression
prettyExpr :: Pretty a => Expr s a -> Doc Ann
prettyExpr = prettySrcExpr . denote
prettySrcExpr :: Pretty a => Expr Src a -> Doc Ann
prettySrcExpr = prettyCharacterSet Unicode
{-| Internal utility for pretty-printing, used when generating element lists
to supply to `enclose` or `enclose'`. This utility indicates that the
compact represent is the same as the multi-line representation for each
element
-}
duplicate :: a -> (a, a)
duplicate x = (x, x)
isWhitespace :: Char -> Bool
isWhitespace c =
case c of
' ' -> True
'\n' -> True
'\t' -> True
'\r' -> True
_ -> False
{-| Used to render inline `Src` spans preserved by the syntax tree
>>> let unusedSourcePos = Text.Megaparsec.SourcePos "" (Text.Megaparsec.mkPos 1) (Text.Megaparsec.mkPos 1)
>>> let nonEmptySrc = Src unusedSourcePos unusedSourcePos "-- Documentation for x\n"
>>> "let" <> " " <> renderSrc id (Just nonEmptySrc) <> "x = 1 in x"
let -- Documentation for x
x = 1 in x
>>> let emptySrc = Src unusedSourcePos unusedSourcePos " "
>>> "let" <> " " <> renderSrc id (Just emptySrc) <> "x = 1 in x"
let x = 1 in x
>>> "let" <> " " <> renderSrc id Nothing <> "x = 1 in x"
let x = 1 in x
-}
renderSrc
:: (Text -> Text)
-- ^ Used to preprocess the comment string (e.g. to strip whitespace)
-> Maybe Src
-- ^ Source span to render (if present)
-> Doc Ann
renderSrc strip (Just (Src {..}))
| not (Text.all isWhitespace srcText) =
Pretty.align (Pretty.concatWith f newLines <> suffix)
where
horizontalSpace c = c == ' ' || c == '\t'
strippedText = strip srcText
suffix =
if Text.null strippedText
then mempty
else if Text.last strippedText == '\n' then mempty else " "
oldLines = Text.splitOn "\n" strippedText
spacePrefix = Text.takeWhile horizontalSpace
commonPrefix a b = case Text.commonPrefixes a b of
Nothing -> ""
Just (c, _, _) -> c
blank = Text.all horizontalSpace
newLines =
case oldLines of
[] ->
[]
l0 : [] ->
Pretty.pretty l0 : []
l0 : l1 : ls ->
let sharedPrefix =
foldl' commonPrefix (spacePrefix l1) (map spacePrefix (filter (not . blank) ls))
perLine l =
case Text.stripPrefix sharedPrefix l of
Nothing -> Pretty.pretty l
Just l' -> Pretty.pretty l'
in Pretty.pretty l0 : map perLine (l1 : ls)
f x y = x <> Pretty.hardline <> y
renderSrc _ _ =
mempty
-- Annotation helpers
keyword, syntax, label, literal, builtin, operator :: Doc Ann -> Doc Ann
keyword = Pretty.annotate Keyword
syntax = Pretty.annotate Syntax
label = Pretty.annotate Label
literal = Pretty.annotate Literal
builtin = Pretty.annotate Builtin
operator = Pretty.annotate Operator
comma, lbracket, rbracket, langle, rangle, lbrace, rbrace, lparen, rparen, pipe, dollar, colon, equals, dot :: Doc Ann
comma = syntax Pretty.comma
lbracket = syntax Pretty.lbracket
rbracket = syntax Pretty.rbracket
langle = syntax Pretty.langle
rangle = syntax Pretty.rangle
lbrace = syntax Pretty.lbrace
rbrace = syntax Pretty.rbrace
lparen = syntax Pretty.lparen
rparen = syntax Pretty.rparen
pipe = syntax Pretty.pipe
dollar = syntax "$"
colon = syntax ":"
equals = syntax "="
dot = syntax "."
lambda :: CharacterSet -> Doc Ann
lambda Unicode = syntax "λ"
lambda ASCII = syntax "\\"
forall :: CharacterSet -> Doc Ann
forall Unicode = syntax "∀"
forall ASCII = syntax "forall "
rarrow :: CharacterSet -> Doc Ann
rarrow Unicode = syntax "→"
rarrow ASCII = syntax "->"
doubleColon :: Doc Ann
doubleColon = syntax "::"
-- | Pretty-print a list
list :: [Doc Ann] -> Doc Ann
list [] = lbracket <> rbracket
list docs =
enclose
(lbracket <> space)
(lbracket <> space)
(comma <> space)
(comma <> space)
(space <> rbracket)
rbracket
(fmap duplicate docs)
-- | Pretty-print union types and literals
angles :: [(Doc Ann, Doc Ann)] -> Doc Ann
angles [] = langle <> rangle
angles docs =
enclose
(langle <> space)
(langle <> space)
(space <> pipe <> space)
(pipe <> space)
(space <> rangle)
rangle
docs
-- | Pretty-print record types and literals
braces :: [(Doc Ann, Doc Ann)] -> Doc Ann
braces [] = lbrace <> rbrace
braces docs =
enclose
(lbrace <> space)
(lbrace <> space)
(comma <> space)
(comma <> space)
(space <> rbrace)
rbrace
docs
hangingBraces :: Int -> [(Doc Ann, Doc Ann)] -> Doc Ann
hangingBraces _ [] =
lbrace <> rbrace
hangingBraces n docs =
Pretty.group
(Pretty.flatAlt
( lbrace
<> Pretty.hardline
<> Pretty.indent n
( mconcat (zipWith combineLong (repeat separator) docsLong)
<> rbrace
)
)
(mconcat (zipWith (<>) (beginShort : repeat separator) docsShort) <> space <> rbrace)
)
where
separator = comma <> space
docsShort = fmap fst docs
docsLong = fmap snd docs
beginShort = lbrace <> space
combineLong x y = x <> y <> Pretty.hardline
-- | Pretty-print anonymous functions and function types
arrows :: CharacterSet -> [(Doc Ann, Doc Ann)] -> Doc Ann
arrows ASCII =
enclose'
""
" "
(" " <> rarrow ASCII <> " ")
(rarrow ASCII <> " ")
arrows Unicode =
enclose'
""
" "
(" " <> rarrow Unicode <> " ")
(rarrow Unicode <> " ")
combine :: CharacterSet -> Text
combine ASCII = "/\\"
combine Unicode = "∧"
combineTypes :: CharacterSet -> Text
combineTypes ASCII = "//\\\\"
combineTypes Unicode = "⩓"
prefer :: CharacterSet -> Text
prefer ASCII = "//"
prefer Unicode = "⫽"
equivalent :: CharacterSet -> Text
equivalent ASCII = "==="
equivalent Unicode = "≡"
{-| Format an expression that holds a variable number of elements, such as a
list, record, or union
-}
enclose
:: Doc ann
-- ^ Beginning document for compact representation
-> Doc ann
-- ^ Beginning document for multi-line representation
-> Doc ann
-- ^ Separator for compact representation
-> Doc ann
-- ^ Separator for multi-line representation
-> Doc ann
-- ^ Ending document for compact representation
-> Doc ann
-- ^ Ending document for multi-line representation
-> [(Doc ann, Doc ann)]
-- ^ Elements to format, each of which is a pair: @(compact, multi-line)@
-> Doc ann
enclose beginShort _ _ _ endShort _ [] =
beginShort <> endShort
where
enclose beginShort beginLong sepShort sepLong endShort endLong docs =
Pretty.group
(Pretty.flatAlt
(Pretty.align
(mconcat (zipWith combineLong (beginLong : repeat sepLong) docsLong) <> endLong)
)
(mconcat (zipWith combineShort (beginShort : repeat sepShort) docsShort) <> endShort)
)
where
docsShort = fmap fst docs
docsLong = fmap snd docs
combineLong x y = x <> y <> Pretty.hardline
combineShort x y = x <> y
{-| Format an expression that holds a variable number of elements without a
trailing document such as nested `let`, nested lambdas, or nested `forall`s
-}
enclose'
:: Doc ann
-- ^ Beginning document for compact representation
-> Doc ann
-- ^ Beginning document for multi-line representation
-> Doc ann
-- ^ Separator for compact representation
-> Doc ann
-- ^ Separator for multi-line representation
-> [(Doc ann, Doc ann)]
-- ^ Elements to format, each of which is a pair: @(compact, multi-line)@
-> Doc ann
enclose' beginShort beginLong sepShort sepLong docs =
Pretty.group (Pretty.flatAlt long short)
where
longLines = zipWith (<>) (beginLong : repeat sepLong) docsLong
long =
Pretty.align (mconcat (Data.List.intersperse Pretty.hardline longLines))
short = mconcat (zipWith (<>) (beginShort : repeat sepShort) docsShort)
docsShort = fmap fst docs
docsLong = fmap snd docs
alpha :: Char -> Bool
alpha c = ('\x41' <= c && c <= '\x5A') || ('\x61' <= c && c <= '\x7A')
digit :: Char -> Bool
digit c = '\x30' <= c && c <= '\x39'
alphaNum :: Char -> Bool
alphaNum c = alpha c || digit c
headCharacter :: Char -> Bool
headCharacter c = alpha c || c == '_'
tailCharacter :: Char -> Bool
tailCharacter c = alphaNum c || c == '_' || c == '-' || c == '/'
-- | Escape a label if it is not valid when unquoted
escapeLabel :: Bool -> Text -> Text
escapeLabel allowReserved l =
case Text.uncons l of
Just (h, t)
| headCharacter h && Text.all tailCharacter t && (allowReserved || not (Data.HashSet.member l reservedIdentifiers))
-> l
_ -> "`" <> l <> "`"
prettyLabelShared :: Bool -> Text -> Doc Ann
prettyLabelShared b l = label (Pretty.pretty (escapeLabel b l))
prettyLabel :: Text -> Doc Ann
prettyLabel = prettyLabelShared False
prettyAnyLabel :: Text -> Doc Ann
prettyAnyLabel = prettyLabelShared True
prettyAnyLabels :: NonEmpty Text -> Doc Ann
prettyAnyLabels =
mconcat . Pretty.punctuate dot . fmap prettyAnyLabel . toList
prettyLabels :: Set Text -> Doc Ann
prettyLabels a
| Data.Set.null (Dhall.Set.toSet a) =
lbrace <> rbrace
| otherwise =
braces (map (duplicate . prettyAnyLabel) (Dhall.Set.toList a))
prettyNumber :: Integer -> Doc Ann
prettyNumber = literal . Pretty.pretty
prettyInt :: Int -> Doc Ann
prettyInt = literal . Pretty.pretty
prettyNatural :: Natural -> Doc Ann
prettyNatural = literal . Pretty.pretty
prettyDouble :: Double -> Doc Ann
prettyDouble = literal . Pretty.pretty
prettyConst :: Const -> Doc Ann
prettyConst Type = builtin "Type"
prettyConst Kind = builtin "Kind"
prettyConst Sort = builtin "Sort"
prettyVar :: Var -> Doc Ann
prettyVar (V x 0) = label (Pretty.unAnnotate (prettyLabel x))
prettyVar (V x n) = label (Pretty.unAnnotate (prettyLabel x <> "@" <> prettyInt n))
prettyEnvironmentVariable :: Text -> Doc ann
prettyEnvironmentVariable t = Pretty.pretty (escapeEnvironmentVariable t)
-- | Escape an environment variable if not a valid Bash environment variable
escapeEnvironmentVariable :: Text -> Text
escapeEnvironmentVariable t
| validBashEnvVar t = t
| otherwise = "\"" <> escapeText_ t <> "\""
where
validBashEnvVar v = case Text.uncons v of
Nothing -> False
Just (c, v') ->
(alpha c || c == '_')
&& Text.all (\c' -> alphaNum c' || c' == '_') v'
{- There is a close correspondence between the pretty-printers in 'prettyCharacterSet'
and the sub-parsers in 'Dhall.Parser.Expression.parsers'. Most pretty-printers are
named after the corresponding parser and the relationship between pretty-printers
exactly matches the relationship between parsers. This leads to the nice emergent
property of automatically getting all the parentheses and precedences right.
This approach has one major disadvantage: you can get an infinite loop if
you add a new constructor to the syntax tree without adding a matching
case the corresponding builder.
-}
{-| Pretty-print an 'Expr' using the given 'CharacterSet'.
'prettyCharacterSet' largely ignores 'Note's. 'Note's do however matter for
the layout of let-blocks:
>>> let inner = Let (Binding Nothing "x" Nothing Nothing Nothing (NaturalLit 1)) (Var (V "x" 0)) :: Expr Src ()
>>> prettyCharacterSet ASCII (Let (Binding Nothing "y" Nothing Nothing Nothing (NaturalLit 2)) inner)
let y = 2 let x = 1 in x
>>> prettyCharacterSet ASCII (Let (Binding Nothing "y" Nothing Nothing Nothing (NaturalLit 2)) (Note (Src unusedSourcePos unusedSourcePos "") inner))
let y = 2 in let x = 1 in x
This means the structure of parsed let-blocks is preserved.
-}
prettyCharacterSet :: Pretty a => CharacterSet -> Expr Src a -> Doc Ann
prettyCharacterSet characterSet expression =
Pretty.group (prettyExpression expression)
where
prettyExpression a0@(Lam _ _ _) =
arrows characterSet (fmap duplicate (docs a0))
where
docs (Lam a b c) = Pretty.group (Pretty.flatAlt long short) : docs c
where
long = (lambda characterSet <> space)
<> Pretty.align
( (lparen <> space)
<> prettyLabel a
<> Pretty.hardline
<> (colon <> space)
<> prettyExpression b
<> Pretty.hardline
<> rparen
)
short = (lambda characterSet <> lparen)
<> prettyLabel a
<> (space <> colon <> space)
<> prettyExpression b
<> rparen
docs (Note _ c) = docs c
docs c = [ prettyExpression c ]
prettyExpression a0@(BoolIf _ _ _) =
Pretty.group (Pretty.flatAlt long short)
where
prefixesLong =
" "
: cycle
[ Pretty.hardline <> keyword "then" <> " "
, Pretty.hardline <> keyword "else" <> " "
]
prefixesShort =
""
: cycle
[ space <> keyword "then" <> space
, space <> keyword "else" <> space
]
longLines = zipWith (<>) prefixesLong (docsLong a0)
long =
Pretty.align (mconcat (Data.List.intersperse Pretty.hardline longLines))
short = mconcat (zipWith (<>) prefixesShort (docsShort a0))
docsLong (BoolIf a b c) =
docLong ++ docsLong c
where
docLong =
[ keyword "if" <> " " <> prettyExpression a
, prettyExpression b
]
docsLong (Note _ c) = docsLong c
docsLong c = [ prettyExpression c ]
docsShort (BoolIf a b c) =
docShort ++ docsShort c
where
docShort =
[ keyword "if" <> " " <> prettyExpression a
, prettyExpression b
]
docsShort (Note _ c) = docsShort c
docsShort c = [ prettyExpression c ]
prettyExpression (Let a0 b0) =
enclose' "" "" space Pretty.hardline
(fmap duplicate (fmap docA (toList as)) ++ [ docB ])
where
MultiLet as b = multiLet a0 b0
stripSpaces = Text.dropAround (\c -> c == ' ' || c == '\t')
-- Strip a single newline character. Needed to ensure idempotency in
-- cases where we add hard line breaks.
stripNewline t =
case Text.uncons t' of
Just ('\n', t'') -> stripSpaces t''
_ -> t'
where t' = stripSpaces t
docA (Binding src0 c src1 Nothing src2 e) =
Pretty.group (Pretty.flatAlt long short)
where
long = keyword "let" <> space
<> Pretty.align
( renderSrc stripSpaces src0
<> prettyLabel c <> space <> renderSrc stripSpaces src1
<> equals <> Pretty.hardline <> renderSrc stripNewline src2
<> " " <> prettyExpression e
)
short = keyword "let" <> space <> renderSrc stripSpaces src0
<> prettyLabel c <> space <> renderSrc stripSpaces src1
<> equals <> space <> renderSrc stripSpaces src2
<> prettyExpression e
docA (Binding src0 c src1 (Just (src3, d)) src2 e) =
keyword "let" <> space
<> Pretty.align
( renderSrc stripSpaces src0
<> prettyLabel c <> Pretty.hardline <> renderSrc stripNewline src1
<> colon <> space <> renderSrc stripSpaces src3 <> prettyExpression d <> Pretty.hardline
<> equals <> space <> renderSrc stripSpaces src2
<> prettyExpression e
)
docB =
( keyword "in" <> " " <> prettyExpression b
, keyword "in" <> " " <> prettyExpression b
)
prettyExpression a0@(Pi _ _ _) =
arrows characterSet (fmap duplicate (docs a0))
where
docs (Pi "_" b c) = prettyOperatorExpression b : docs c
docs (Pi a b c) = Pretty.group (Pretty.flatAlt long short) : docs c
where
long = forall characterSet <> space
<> Pretty.align
( lparen <> space
<> prettyLabel a
<> Pretty.hardline
<> colon <> space
<> prettyExpression b
<> Pretty.hardline
<> rparen
)
short = forall characterSet <> lparen
<> prettyLabel a
<> space <> colon <> space
<> prettyExpression b
<> rparen
docs (Note _ c) = docs c
docs c = [ prettyExpression c ]
prettyExpression (Assert a) =
Pretty.group (Pretty.flatAlt long short)
where
short = keyword "assert" <> " " <> colon <> " " <> prettyExpression a
long =
Pretty.align
( " " <> keyword "assert"
<> Pretty.hardline <> colon <> " " <> prettyExpression a
)
prettyExpression (Note _ a) =
prettyExpression a
prettyExpression a0 =
prettyAnnotatedExpression a0
prettyAnnotatedExpression :: Pretty a => Expr Src a -> Doc Ann
prettyAnnotatedExpression (Merge a b (Just c)) =
Pretty.group (Pretty.flatAlt long short)
where
long =
Pretty.align
( keyword "merge"
<> Pretty.hardline
<> Pretty.indent 2 (prettyImportExpression a)
<> Pretty.hardline
<> Pretty.indent 2 (prettyImportExpression b)
<> Pretty.hardline
<> colon <> space
<> prettyApplicationExpression c
)
short = keyword "merge" <> space
<> prettyImportExpression a
<> " "
<> prettyImportExpression b
<> space <> colon <> space
<> prettyApplicationExpression c
prettyAnnotatedExpression (ToMap a (Just b)) =
Pretty.group (Pretty.flatAlt long short)
where
long =
Pretty.align
( keyword "toMap"
<> Pretty.hardline
<> Pretty.indent 2 (prettyImportExpression a)
<> Pretty.hardline
<> colon <> space
<> prettyApplicationExpression b
)
short = keyword "toMap" <> space
<> prettyImportExpression a
<> space <> colon <> space
<> prettyApplicationExpression b
prettyAnnotatedExpression a0@(Annot _ _) =
enclose'
""
" "
(" " <> colon <> " ")
(colon <> space)
(fmap duplicate (docs a0))
where
docs (Annot a b) = prettyOperatorExpression a : docs b
docs (Note _ b) = docs b
docs b = [ prettyExpression b ]
prettyAnnotatedExpression (ListLit (Just a) b) =
list (map prettyExpression (Data.Foldable.toList b))
<> " : "
<> prettyApplicationExpression a
prettyAnnotatedExpression (Note _ a) =
prettyAnnotatedExpression a
prettyAnnotatedExpression a0 =
prettyOperatorExpression a0
prettyOperatorExpression :: Pretty a => Expr Src a -> Doc Ann
prettyOperatorExpression = prettyImportAltExpression
prettyOperator :: Text -> [Doc Ann] -> Doc Ann
prettyOperator op docs =
enclose'
""
prefix
(" " <> operator (Pretty.pretty op) <> " ")
(operator (Pretty.pretty op) <> spacer)
(reverse (fmap duplicate docs))
where
prefix = if Text.length op == 1 then " " else " "
spacer = if Text.length op == 1 then " " else " "
prettyImportAltExpression :: Pretty a => Expr Src a -> Doc Ann
prettyImportAltExpression a0@(ImportAlt _ _) =
prettyOperator "?" (docs a0)
where
docs (ImportAlt a b) = prettyOrExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyOrExpression b ]
prettyImportAltExpression (Note _ a) =
prettyImportAltExpression a
prettyImportAltExpression a0 =
prettyOrExpression a0
prettyOrExpression :: Pretty a => Expr Src a -> Doc Ann
prettyOrExpression a0@(BoolOr _ _) =
prettyOperator "||" (docs a0)
where
docs (BoolOr a b) = prettyPlusExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyPlusExpression b ]
prettyOrExpression (Note _ a) =
prettyOrExpression a
prettyOrExpression a0 =
prettyPlusExpression a0
prettyPlusExpression :: Pretty a => Expr Src a -> Doc Ann
prettyPlusExpression a0@(NaturalPlus _ _) =
prettyOperator "+" (docs a0)
where
docs (NaturalPlus a b) = prettyTextAppendExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyTextAppendExpression b ]
prettyPlusExpression (Note _ a) =
prettyPlusExpression a
prettyPlusExpression a0 =
prettyTextAppendExpression a0
prettyTextAppendExpression :: Pretty a => Expr Src a -> Doc Ann
prettyTextAppendExpression a0@(TextAppend _ _) =
prettyOperator "++" (docs a0)
where
docs (TextAppend a b) = prettyListAppendExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyListAppendExpression b ]
prettyTextAppendExpression (Note _ a) =
prettyTextAppendExpression a
prettyTextAppendExpression a0 =
prettyListAppendExpression a0
prettyListAppendExpression :: Pretty a => Expr Src a -> Doc Ann
prettyListAppendExpression a0@(ListAppend _ _) =
prettyOperator "#" (docs a0)
where
docs (ListAppend a b) = prettyAndExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyAndExpression b ]
prettyListAppendExpression (Note _ a) =
prettyListAppendExpression a
prettyListAppendExpression a0 =
prettyAndExpression a0
prettyAndExpression :: Pretty a => Expr Src a -> Doc Ann
prettyAndExpression a0@(BoolAnd _ _) =
prettyOperator "&&" (docs a0)
where
docs (BoolAnd a b) = prettyCombineExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyCombineExpression b ]
prettyAndExpression (Note _ a) =
prettyAndExpression a
prettyAndExpression a0 =
prettyCombineExpression a0
prettyCombineExpression :: Pretty a => Expr Src a -> Doc Ann
prettyCombineExpression a0@(Combine _ _ _) =
prettyOperator (combine characterSet) (docs a0)
where
docs (Combine _ a b) = prettyPreferExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyPreferExpression b ]
prettyCombineExpression (Note _ a) =
prettyCombineExpression a
prettyCombineExpression a0 =
prettyPreferExpression a0
prettyPreferExpression :: Pretty a => Expr Src a -> Doc Ann
prettyPreferExpression a0@(Prefer _ _) =
prettyOperator (prefer characterSet) (docs a0)
where
docs (Prefer a b) = prettyCombineTypesExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyCombineTypesExpression b ]
prettyPreferExpression (Note _ a) =
prettyPreferExpression a
prettyPreferExpression a0 =
prettyCombineTypesExpression a0
prettyCombineTypesExpression :: Pretty a => Expr Src a -> Doc Ann
prettyCombineTypesExpression a0@(CombineTypes _ _) =
prettyOperator (combineTypes characterSet) (docs a0)
where
docs (CombineTypes a b) = prettyTimesExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyTimesExpression b ]
prettyCombineTypesExpression (Note _ a) =
prettyCombineTypesExpression a
prettyCombineTypesExpression a0 =
prettyTimesExpression a0
prettyTimesExpression :: Pretty a => Expr Src a -> Doc Ann
prettyTimesExpression a0@(NaturalTimes _ _) =
prettyOperator "*" (docs a0)
where
docs (NaturalTimes a b) = prettyEqualExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyEqualExpression b ]
prettyTimesExpression (Note _ a) =
prettyTimesExpression a
prettyTimesExpression a0 =
prettyEqualExpression a0
prettyEqualExpression :: Pretty a => Expr Src a -> Doc Ann
prettyEqualExpression a0@(BoolEQ _ _) =
prettyOperator "==" (docs a0)
where
docs (BoolEQ a b) = prettyNotEqualExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyNotEqualExpression b ]
prettyEqualExpression (Note _ a) =
prettyEqualExpression a
prettyEqualExpression a0 =
prettyNotEqualExpression a0
prettyNotEqualExpression :: Pretty a => Expr Src a -> Doc Ann
prettyNotEqualExpression a0@(BoolNE _ _) =
prettyOperator "!=" (docs a0)
where
docs (BoolNE a b) = prettyEquivalentExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyEquivalentExpression b ]
prettyNotEqualExpression (Note _ a) =
prettyNotEqualExpression a
prettyNotEqualExpression a0 =
prettyEquivalentExpression a0
prettyEquivalentExpression :: Pretty a => Expr Src a -> Doc Ann
prettyEquivalentExpression a0@(Equivalent _ _) =
prettyOperator (equivalent characterSet) (docs a0)
where
docs (Equivalent a b) = prettyApplicationExpression b : docs a
docs (Note _ b) = docs b
docs b = [ prettyApplicationExpression b ]
prettyEquivalentExpression (Note _ a) =
prettyEquivalentExpression a
prettyEquivalentExpression a0 =
prettyApplicationExpression a0
prettyApplicationExpression :: Pretty a => Expr Src a -> Doc Ann
prettyApplicationExpression = go []
where
go args = \case
App a b -> go (b : args) a
Some a -> app (builtin "Some") (a : args)
Merge a b Nothing -> app (keyword "merge") (a : b : args)
ToMap a Nothing -> app (keyword "toMap") (a : args)
Note _ b -> go args b
e | null args -> prettyImportExpression e -- just a performance optimization
| otherwise -> app (prettyImportExpression e) args
app f args =
enclose'
"" "" " " ""
( duplicate f
: map (fmap (Pretty.indent 2) . duplicate . prettyImportExpression) args
)
prettyImportExpression :: Pretty a => Expr Src a -> Doc Ann
prettyImportExpression (Embed a) =
Pretty.pretty a
prettyImportExpression (Note _ a) =
prettyImportExpression a
prettyImportExpression a0 =
prettyCompletionExpression a0
prettyCompletionExpression :: Pretty a => Expr Src a -> Doc Ann
prettyCompletionExpression (RecordCompletion a b) =
case shallowDenote b of
RecordLit kvs ->
Pretty.align
( prettySelectorExpression a
<> doubleColon
<> prettyCompletionLit 0 kvs
)
_ -> prettySelectorExpression a
<> doubleColon
<> prettySelectorExpression b
prettyCompletionExpression (Note _ a) =
prettyCompletionExpression a
prettyCompletionExpression a0 =
prettySelectorExpression a0
prettySelectorExpression :: Pretty a => Expr Src a -> Doc Ann
prettySelectorExpression (Field a b) =
prettySelectorExpression a <> dot <> prettyAnyLabel b
prettySelectorExpression (Project a (Left b)) =
prettySelectorExpression a <> dot <> prettyLabels b
prettySelectorExpression (Project a (Right b)) =
prettySelectorExpression a
<> dot
<> lparen
<> prettyExpression b
<> rparen
prettySelectorExpression (Note _ b) =
prettySelectorExpression b
prettySelectorExpression a0 =
prettyPrimitiveExpression a0
prettyPrimitiveExpression :: Pretty a => Expr Src a -> Doc Ann
prettyPrimitiveExpression (Var a) =
prettyVar a
prettyPrimitiveExpression (Const k) =
prettyConst k
prettyPrimitiveExpression Bool =
builtin "Bool"
prettyPrimitiveExpression Natural =
builtin "Natural"
prettyPrimitiveExpression NaturalFold =
builtin "Natural/fold"
prettyPrimitiveExpression NaturalBuild =
builtin "Natural/build"
prettyPrimitiveExpression NaturalIsZero =
builtin "Natural/isZero"
prettyPrimitiveExpression NaturalEven =
builtin "Natural/even"
prettyPrimitiveExpression NaturalOdd =
builtin "Natural/odd"
prettyPrimitiveExpression NaturalToInteger =
builtin "Natural/toInteger"
prettyPrimitiveExpression NaturalShow =
builtin "Natural/show"
prettyPrimitiveExpression NaturalSubtract =
builtin "Natural/subtract"
prettyPrimitiveExpression Integer =
builtin "Integer"
prettyPrimitiveExpression IntegerClamp =
builtin "Integer/clamp"
prettyPrimitiveExpression IntegerNegate =
builtin "Integer/negate"
prettyPrimitiveExpression IntegerShow =
builtin "Integer/show"
prettyPrimitiveExpression IntegerToDouble =
builtin "Integer/toDouble"
prettyPrimitiveExpression Double =
builtin "Double"
prettyPrimitiveExpression DoubleShow =
builtin "Double/show"
prettyPrimitiveExpression Text =
builtin "Text"
prettyPrimitiveExpression TextShow =
builtin "Text/show"
prettyPrimitiveExpression List =
builtin "List"
prettyPrimitiveExpression ListBuild =
builtin "List/build"
prettyPrimitiveExpression ListFold =
builtin "List/fold"
prettyPrimitiveExpression ListLength =
builtin "List/length"
prettyPrimitiveExpression ListHead =
builtin "List/head"
prettyPrimitiveExpression ListLast =
builtin "List/last"
prettyPrimitiveExpression ListIndexed =
builtin "List/indexed"
prettyPrimitiveExpression ListReverse =
builtin "List/reverse"
prettyPrimitiveExpression Optional =
builtin "Optional"
prettyPrimitiveExpression None =
builtin "None"
prettyPrimitiveExpression OptionalFold =
builtin "Optional/fold"
prettyPrimitiveExpression OptionalBuild =
builtin "Optional/build"
prettyPrimitiveExpression (BoolLit True) =
builtin "True"
prettyPrimitiveExpression (BoolLit False) =
builtin "False"
prettyPrimitiveExpression (IntegerLit a)
| 0 <= a = literal "+" <> prettyNumber a
| otherwise = prettyNumber a
prettyPrimitiveExpression (NaturalLit a) =
prettyNatural a
prettyPrimitiveExpression (DoubleLit (DhallDouble a)) =
prettyDouble a
prettyPrimitiveExpression (TextLit a) =
prettyChunks a
prettyPrimitiveExpression (Record a) =
prettyRecord a
prettyPrimitiveExpression (RecordLit a) =
prettyRecordLit a
prettyPrimitiveExpression (Union a) =
prettyUnion a
prettyPrimitiveExpression (ListLit Nothing b) =
list (map prettyExpression (Data.Foldable.toList b))
prettyPrimitiveExpression (Note _ b) =
prettyPrimitiveExpression b
prettyPrimitiveExpression a =
Pretty.group (Pretty.flatAlt long short)
where
long =
Pretty.align
(lparen <> space <> prettyExpression a <> Pretty.hardline <> rparen)
short = lparen <> prettyExpression a <> rparen
prettyKeyValue
:: Pretty a => (k -> Doc Ann) -> Doc Ann -> (k, Expr Src a) -> (Doc Ann, Doc Ann)
prettyKeyValue prettyKey separator (key, val) =
duplicate (Pretty.group (Pretty.flatAlt long short))
where
completion _T r =
" "
<> prettySelectorExpression _T
<> doubleColon
<> case shallowDenote r of
RecordLit kvs ->
prettyCompletionLit 2 kvs
_ ->
prettySelectorExpression r
short = prettyKey key
<> " "
<> separator
<> " "
<> prettyExpression val
long =
prettyKey key
<> " "
<> separator
<> case shallowDenote val of
Some val' ->
" " <> builtin "Some"
<> case shallowDenote val' of
RecordCompletion _T r ->
completion _T r
ListLit _ xs
| not (null xs) ->
Pretty.hardline
<> " "
<> prettyExpression val'
_ -> Pretty.hardline
<> " "
<> prettyImportExpression val'
ToMap val' Nothing ->
" " <> keyword "toMap"
<> case shallowDenote val' of
RecordCompletion _T r ->
completion _T r
_ -> Pretty.hardline
<> " "
<> prettyImportExpression val'
RecordCompletion _T r ->
completion _T r
ListLit _ xs
| not (null xs) ->
Pretty.hardline
<> " "
<> prettyExpression val
_ ->
Pretty.hardline
<> " "
<> prettyExpression val
prettyRecord :: Pretty a => Map Text (Expr Src a) -> Doc Ann
prettyRecord =
braces . map (prettyKeyValue prettyAnyLabel colon) . Map.toList
prettyRecordLit :: Pretty a => Map Text (Expr Src a) -> Doc Ann
prettyRecordLit a
| Data.Foldable.null a =
lbrace <> equals <> rbrace
| otherwise =
braces (map prettyRecordEntry (Map.toList consolidated))
where
consolidated = consolidateRecordLiteral a
prettyRecordEntry = prettyKeyValue prettyAnyLabels equals
prettyCompletionLit
:: Pretty a => Int -> Map Text (Expr Src a) -> Doc Ann
prettyCompletionLit n a
| Data.Foldable.null a =
lbrace <> equals <> rbrace
| otherwise =
hangingBraces n (map prettyRecordEntry (Map.toList consolidated))
where
consolidated = consolidateRecordLiteral a
prettyRecordEntry = prettyKeyValue prettyAnyLabels equals
prettyAlternative (key, Just val) = prettyKeyValue prettyAnyLabel colon (key, val)
prettyAlternative (key, Nothing ) = duplicate (prettyAnyLabel key)
prettyUnion :: Pretty a => Map Text (Maybe (Expr Src a)) -> Doc Ann
prettyUnion =
angles . map prettyAlternative . Map.toList
prettyChunks :: Pretty a => Chunks Src a -> Doc Ann
prettyChunks chunks@(Chunks a b)
| anyText (== '\n') =
if not (null a) || anyText (/= '\n')
then long
else Pretty.group (Pretty.flatAlt long short)
| otherwise =
short
where
long =
Pretty.align
( literal "''" <> Pretty.hardline
<> Pretty.align
(foldMap prettyMultilineChunk a' <> prettyMultilineText b')
<> literal "''"
)
where
Chunks a' b' = multilineChunks chunks
short =
literal "\"" <> foldMap prettyChunk a <> literal (prettyText b <> "\"")
anyText predicate = any (\(text, _) -> Text.any predicate text) a || Text.any predicate b
prettyMultilineChunk (c, d) =
prettyMultilineText c
<> dollar
<> lbrace
<> prettyExpression d
<> rbrace
prettyMultilineText text = mconcat docs
where
lines_ = Text.splitOn "\n" (escapeSingleQuotedText text)
-- Annotate only non-empty lines so trailing whitespace can be
-- removed on empty ones.
prettyLine line =
(if Text.null line then id else literal)
(Pretty.pretty line)
docs =
Data.List.intersperse Pretty.hardline (map prettyLine lines_)
prettyChunk (c, d) =
prettyText c
<> syntax "${"
<> prettyExpression d
<> syntax rbrace
prettyText t = literal (Pretty.pretty (escapeText_ t))
-- | Prepare 'Chunks' for multi-line formatting by escaping problematic
-- character sequences via string interpolations
--
-- >>> multilineChunks (Chunks [] "\n \tx")
-- Chunks [("\n",TextLit (Chunks [] " \t"))] "x"
-- >>> multilineChunks (Chunks [] "\n\NUL\b\f\t")
-- Chunks [("\n",TextLit (Chunks [] "\NUL\b\f"))] "\t"
multilineChunks :: Chunks s a -> Chunks s a
multilineChunks =
escapeTrailingSingleQuote
. escapeControlCharacters
. escapeSharedWhitespacePrefix
-- | Escape any leading whitespace shared by all lines
--
-- This ensures that significant shared leading whitespace is not stripped
--
-- >>> escapeSharedWhitespacePrefix (Chunks [] "\n \tx")
-- Chunks [("\n",TextLit (Chunks [] " \t"))] "x"
-- >>> escapeSharedWhitespacePrefix (Chunks [("\n",Var (V "x" 0))] " ")
-- Chunks [("\n",Var (V "x" 0))] " "
-- >>> escapeSharedWhitespacePrefix (Chunks [("\n ",Var (V "x" 0))] "")
-- Chunks [("\n",TextLit (Chunks [] " ")),("",Var (V "x" 0))] ""
-- >>> escapeSharedWhitespacePrefix (Chunks [("\n ",Var (V "x" 0))] "\n")
-- Chunks [("\n ",Var (V "x" 0))] "\n"
-- >>> escapeSharedWhitespacePrefix (Chunks [] " ")
-- Chunks [("",TextLit (Chunks [] " "))] ""
escapeSharedWhitespacePrefix :: Chunks s a -> Chunks s a
escapeSharedWhitespacePrefix literal_ = unlinesLiteral literals₁
where
literals₀ = linesLiteral literal_
sharedPrefix = longestSharedWhitespacePrefix literals₀
stripPrefix = Text.drop (Text.length sharedPrefix)
escapeSharedPrefix (Chunks [] prefix₀)
| Text.isPrefixOf sharedPrefix prefix₀ =
Chunks [ ("", TextLit (Chunks [] sharedPrefix)) ] prefix₁
where
prefix₁ = stripPrefix prefix₀
escapeSharedPrefix (Chunks ((prefix₀, y) : xys) z)
| Text.isPrefixOf sharedPrefix prefix₀ =
Chunks (("", TextLit (Chunks [] sharedPrefix)) : (prefix₁, y) : xys) z
where
prefix₁ = stripPrefix prefix₀
escapeSharedPrefix line = line
literals₁
| not (Text.null sharedPrefix) = fmap escapeSharedPrefix literals₀
| otherwise = literals₀
-- | Escape control characters by moving them into string interpolations
--
-- >>> escapeControlCharacters (Chunks [] "\n\NUL\b\f\t")
-- Chunks [("\n",TextLit (Chunks [] "\NUL\b\f"))] "\t"
escapeControlCharacters :: Chunks s a -> Chunks s a
escapeControlCharacters (Chunks as0 b0) = Chunks as1 b1
where
as1 = foldr f (map toChunk bs) as0
(bs, b1) = splitOnPredicate predicate b0
f (t0, e) chunks = map toChunk ts1 ++ (t1, e) : chunks
where
(ts1, t1) = splitOnPredicate predicate t0
predicate c = Data.Char.isControl c && c /= ' ' && c /= '\t' && c /= '\n'
toChunk (t0, t1) = (t0, TextLit (Chunks [] t1))
-- | Split `Text` on a predicate, preserving all parts of the original string.
--
-- >>> splitOnPredicate (== 'x') ""
-- ([],"")
-- >>> splitOnPredicate (== 'x') " xx "
-- ([(" ","xx")]," ")
-- >>> splitOnPredicate (== 'x') "xx"
-- ([("","xx")],"")
--
-- prop> \(Fun _ p) s -> let {t = Text.pack s; (as, b) = splitOnPredicate p t} in foldMap (uncurry (<>)) as <> b == t
splitOnPredicate :: (Char -> Bool) -> Text -> ([(Text, Text)], Text)
splitOnPredicate p t = case Text.break p t of
(a, "") -> ([], a)
(a, b) -> case Text.span p b of
(c, d) -> case splitOnPredicate p d of
(e, f) -> ((a, c) : e, f)
-- | Escape a trailing single quote by moving it into a string interpolation
--
-- Otherwise the multiline-string would end with @'''@, which would be parsed
-- as an escaped @''@.
--
-- >>> escapeTrailingSingleQuote (Chunks [] "\n'")
-- Chunks [("\n",TextLit (Chunks [] "'"))] ""
escapeTrailingSingleQuote :: Chunks s a -> Chunks s a
escapeTrailingSingleQuote chunks@(Chunks as b) =
case Text.unsnoc b of
Just (b', '\'') -> Chunks (as ++ [(b', TextLit (Chunks [] "'"))]) ""
_ -> chunks
-- | Pretty-print a value
pretty_ :: Pretty a => a -> Text
pretty_ = prettyToStrictText
{- This utility function converts
`{ x = { y = { z = 1 } } }` to `{ x.y.z. = 1 }`
-}
consolidateRecordLiteral
:: Map Text (Expr s a) -> Map (NonEmpty Text) (Expr s a)
consolidateRecordLiteral = Map.fromList . fmap adapt . Map.toList
where
adapt :: (Text, Expr s a) -> (NonEmpty Text, Expr s a)
adapt (key, expression) =
case shallowDenote expression of
RecordLit m ->
case fmap adapt (Map.toList m) of
[ (keys, expression') ] ->
(NonEmpty.cons key keys, expression')
_ ->
(pure key, RecordLit m)
_ ->
(pure key, expression)
-- | Escape a `Text` literal using Dhall's escaping rules for single-quoted
-- @Text@
escapeSingleQuotedText :: Text -> Text
escapeSingleQuotedText inputText = outputText
where
outputText = substitute "${" "''${" (substitute "''" "'''" inputText)
substitute before after = Text.intercalate after . Text.splitOn before
{-| Escape a `Text` literal using Dhall's escaping rules
Note that the result does not include surrounding quotes
-}
escapeText_ :: Text -> Text
escapeText_ text = Text.concatMap adapt text
where
adapt c
| '\x20' <= c && c <= '\x21' = Text.singleton c
-- '\x22' == '"'
| '\x23' == c = Text.singleton c
-- '\x24' == '$'
| '\x25' <= c && c <= '\x5B' = Text.singleton c
-- '\x5C' == '\\'
| '\x5D' <= c && c <= '\x10FFFF' = Text.singleton c
| c == '"' = "\\\""
| c == '$' = "\\$"
| c == '\\' = "\\\\"
| c == '\b' = "\\b"
| c == '\f' = "\\f"
| c == '\n' = "\\n"
| c == '\r' = "\\r"
| c == '\t' = "\\t"
| otherwise = "\\u" <> showDigits (Data.Char.ord c)
showDigits r0 = Text.pack (map showDigit [q1, q2, q3, r3])
where
(q1, r1) = r0 `quotRem` 4096
(q2, r2) = r1 `quotRem` 256
(q3, r3) = r2 `quotRem` 16
showDigit n
| n < 10 = Data.Char.chr (Data.Char.ord '0' + n)
| otherwise = Data.Char.chr (Data.Char.ord 'A' + n - 10)
prettyToString :: Pretty a => a -> String
prettyToString =
Pretty.renderString . layout . Pretty.pretty
docToStrictText :: Doc ann -> Text.Text
docToStrictText = Pretty.renderStrict . layout
prettyToStrictText :: Pretty a => a -> Text.Text
prettyToStrictText = docToStrictText . Pretty.pretty
-- | Layout using 'layoutOpts'
--
-- Tries hard to fit the document into 80 columns.
--
-- This also removes trailing space characters (@' '@) /unless/
-- they are enclosed in an annotation.
layout :: Pretty.Doc ann -> Pretty.SimpleDocStream ann
layout = Pretty.removeTrailingWhitespace . Pretty.layoutSmart layoutOpts
-- | Default layout options
layoutOpts :: Pretty.LayoutOptions
layoutOpts =
Pretty.defaultLayoutOptions
{ Pretty.layoutPageWidth = Pretty.AvailablePerLine 80 1.0 }
{- $setup
>>> import Test.QuickCheck (Fun(..))
-}