hasktags-0.71.0: src/Hasktags.hs
{-# LANGUAGE CPP #-}
{-# LANGUAGE RecordWildCards #-}
-- should this be named Data.Hasktags or such?
module Hasktags (
FileData,
generate,
findThings,
findThingsInBS,
Mode(..),
TagsFile(..),
Tags(..),
-- TODO think about these: Must they be exported ?
getOutFile,
dirToFiles
) where
import Control.Monad (when)
import Control.Arrow ((***))
import qualified Data.ByteString.Char8 as BS (ByteString, readFile, unpack)
import qualified Data.ByteString.UTF8 as BS8 (fromString)
import Data.Char (isSpace)
import Data.String (IsString(..))
import Data.List (isPrefixOf, isSuffixOf, groupBy,
tails, nub)
import Data.Maybe (maybeToList)
import DebugShow (trace_)
import System.Directory (doesDirectoryExist, doesFileExist,
getDirectoryContents,
getModificationTime,
canonicalizePath,
#if MIN_VERSION_directory(1,3,0)
pathIsSymbolicLink)
#else
isSymbolicLink)
#endif
import System.FilePath ((</>))
import System.IO (Handle, IOMode, hClose, openFile, stdout)
import Tags (FileData (..), FileName,
FoundThing (..),
FoundThingType (FTClass, FTCons, FTConsAccessor, FTConsGADT, FTData, FTDataGADT, FTFuncImpl, FTFuncTypeDef, FTInstance, FTModule, FTNewtype, FTPattern, FTPatternTypeDef, FTType),
Pos (..), Scope, mywords,
writectagsfile, writeetagsfile)
import Text.JSON.Generic (decodeJSON, encodeJSON)
-- search for definitions of things
-- we do this by looking for the following patterns:
-- data XXX = ... giving a datatype location
-- newtype XXX = ... giving a newtype location
-- bla :: ... giving a function location
--
-- by doing it this way, we avoid picking up local definitions
-- (whether this is good or not is a matter for debate)
--
-- We generate both CTAGS and ETAGS format tags files
-- The former is for use in most sensible editors, while EMACS uses ETAGS
-- alternatives: http://haskell.org/haskellwiki/Tags
{- .hs or literate .lhs haskell file?
Really not a easy question - maybe there is an answer - I don't know
.hs -> non literate haskel file
.lhs -> literate haskell file
.chs -> is this always plain?
.whatsoever -> try to get to know the answer (*)
contains any '> ... ' line -> interpreted as literate
else non literate
(*) This is difficult because
System.Log.Logger is using
{-
[...]
> module Example where
> [...]
-}
module System.Log.Logger(
so it might looks like beeing a .lhs file
My first fix was checking for \\begin occurence (doesn't work because HUnit is
using > but no \\begin)
Further ideas:
* use unlit executable distributed with ghc or the like and check for
errors?
(Will this work if cpp is used as well ?)
* Remove comments before checking for '> ..'
does'nt work because {- -} may be unbalanced in literate comments
So my solution is : take file extension and keep guessing code for all unkown
files
-}
-- Reference: http://ctags.sourceforge.net/FORMAT
-- | getOutFile scans the modes searching for output redirection
-- if not found, open the file with name passed as parameter.
-- Handle special file -, which is stdout
getOutFile :: String -> IOMode -> IO Handle
getOutFile filepath openMode
| "-" == filepath = return stdout
| otherwise = openFile filepath openMode
data TagsFile = TagsFile
{ _ctagsFile :: FilePath
, _etagsFile :: FilePath
}
instance Show TagsFile where
show TagsFile{..} = "ctags: " ++ _ctagsFile ++ ", etags: " ++ _etagsFile
instance IsString TagsFile where
fromString s = TagsFile s s
data Tags =
Ctags
| Etags
| Both
deriving Show
data Mode = Mode
{ _tags :: Tags
, _extendedCtag :: Bool
, _appendTags :: IOMode
, _outputFile :: TagsFile
, _cacheData :: Bool
, _followSymlinks :: Bool
, _suffixes :: [String]
, _absoluteTagPaths :: Bool
} deriving Show
data Token = Token String Pos
| NewLine Int -- space 8*" " = "\t"
deriving (Eq)
instance Show Token where
-- show (Token t (Pos _ l _ _) ) = "Token " ++ t ++ " " ++ (show l)
show (Token t (Pos _ _l _ _) ) = " " ++ t ++ " "
show (NewLine i) = "NewLine " ++ show i
tokenString :: Token -> String
tokenString (Token s _) = s
tokenString (NewLine _) = "\n"
isNewLine :: Maybe Int -> Token -> Bool
isNewLine Nothing (NewLine _) = True
isNewLine (Just c) (NewLine c') = c == c'
isNewLine _ _ = False
trimNewlines :: [Token] -> [Token]
trimNewlines = filter (not . isNewLine Nothing)
generate :: Mode -> [FilePath] -> IO ()
generate Mode{..} files = do
files_or_dirs <- if _absoluteTagPaths
then mapM canonicalizePath files
else return files
filenames <- (nub . concat) <$> mapM (dirToFiles _followSymlinks _suffixes) files_or_dirs
filedata <- mapM (findWithCache _cacheData) filenames
writeTags _tags filedata
where
writeTags Ctags filedata = writeFile' _ctagsFile (writectagsfile _extendedCtag filedata)
writeTags Etags filedata = writeFile' _etagsFile (writeetagsfile filedata)
writeTags Both filedata = writeTags Ctags filedata >> writeTags Etags filedata
writeFile' :: FilePath -> (Handle -> IO ()) -> IO ()
writeFile' name f = do
file <- getOutFile name _appendTags
f file
hClose file
TagsFile{..} = _outputFile
-- Find the definitions in a file, or load from cache if the file
-- hasn't changed since last time.
findWithCache :: Bool -> FileName -> IO FileData
findWithCache cache filename = do
cacheExists <- if cache then doesFileExist cacheFilename else return False
if cacheExists
then do fileModified <- getModificationTime filename
cacheModified <- getModificationTime cacheFilename
if cacheModified > fileModified
then do bytes <- BS.readFile cacheFilename
return (decodeJSON (BS.unpack bytes))
else findAndCache
else findAndCache
where cacheFilename = filenameToTagsName filename
filenameToTagsName = (++"tags") . reverse . dropWhile (/='.') . reverse
findAndCache = do
filedata <- findThings filename
when cache (writeFile cacheFilename (encodeJSON filedata))
return filedata
-- eg Data.Text says that using ByteStrings could be fastest depending on ghc
-- platform and whatnot - so let's keep the hacky BS.readFile >>= BS.unpack
-- usage till there is a problem, still need to match utf-8 chars like this: ⇒
-- to get correct class names, eg MonadBaseControl case (testcase testcases/monad-base-control.hs)
-- so use the same conversion which is applied to files when they got read ..
utf8_to_char8_hack :: String -> String
utf8_to_char8_hack = BS.unpack . BS8.fromString
-- Find the definitions in a file
findThings :: FileName -> IO FileData
findThings filename =
findThingsInBS filename <$> BS.readFile filename
findThingsInBS :: String -> BS.ByteString -> FileData
findThingsInBS filename bs = do
let aslines = lines $ BS.unpack bs
let stripNonHaskellLines = let
emptyLine = all (all isSpace . tokenString)
. filter (not . isNewLine Nothing)
cppLine (_nl:t:_) = ("#" `isPrefixOf`) $ tokenString t
cppLine _ = False
in filter (not . emptyLine) . filter (not . cppLine)
let debugStep m s = trace_ (m ++ " result") s s
let (isLiterate, slines) =
debugStep "fromLiterate"
$ fromLiterate filename
$ zip aslines [0..]
-- remove -- comments, then break each line into tokens (adding line
-- numbers)
-- then remove {- -} comments
-- split by lines again ( to get indent
let
(fileLines, numbers)
= unzip slines
let tokenLines {- :: [[Token]] -} =
debugStep "stripNonHaskellLines" $ stripNonHaskellLines
$ debugStep "stripslcomments" $ stripslcomments
$ debugStep "splitByNL" $ splitByNL Nothing
$ debugStep "stripblockcomments pipe" $ stripblockcomments
$ concat
$ zipWith3 (withline filename)
(map
(filter (not . all isSpace) . mywords False)
fileLines)
fileLines
numbers
-- TODO ($defines / empty lines etc)
-- separate by top level declarations (everything starting with the
-- same topmost indentation is what I call section here)
-- so that z in
-- let x = 7
-- z = 20
-- won't be found as function
let topLevelIndent = debugStep "top level indent" $ getTopLevelIndent isLiterate tokenLines
let sections = map tail -- strip leading NL (no longer needed)
$ filter (not . null)
$ splitByNL (Just topLevelIndent )
$ concat (trace_ "tokenLines" tokenLines tokenLines)
-- only take one of
-- a 'x' = 7
-- a _ = 0
let filterAdjacentFuncImpl = map head . groupBy (\(FoundThing t1 n1 (Pos f1 _ _ _))
(FoundThing t2 n2 (Pos f2 _ _ _))
-> f1 == f2
&& n1 == n2
&& areFuncImpls t1 t2)
areFuncImpls (FTFuncImpl _) (FTFuncImpl _) = True
areFuncImpls _ _ = False
let iCI = map head . groupBy (\(FoundThing t1 n1 (Pos f1 l1 _ _))
(FoundThing t2 n2 (Pos f2 l2 _ _))
-> f1 == f2
&& n1 == n2
&& skipCons t1 t2
&& ((<= 7) $ abs $ l2 - l1))
skipCons FTData (FTCons _ _) = False
skipCons FTDataGADT (FTConsGADT _) = False
skipCons _ _ = True
let things = iCI $ filterAdjacentFuncImpl $ concatMap (flip findstuff Nothing .
(\s -> trace_ "section in findThingsInBS" s s)) sections
let
-- If there's a module with the same name of another definition, we
-- are not interested in the module, but only in the definition.
uniqueModuleName (FoundThing FTModule moduleName _)
= not
$ any (\(FoundThing thingType thingName _)
-> thingType /= FTModule && thingName == moduleName) things
uniqueModuleName _ = True
FileData filename $ filter uniqueModuleName things
-- Create tokens from words, by recording their line number
-- and which token they are through that line
withline :: FileName -> [String] -> String -> Int -> [Token]
withline filename sourceWords fullline i =
let countSpaces (' ':xs) = 1 + countSpaces xs
countSpaces ('\t':xs) = 8 + countSpaces xs
countSpaces _ = 0
in NewLine (countSpaces fullline)
: zipWith (\w t -> Token w (Pos filename i t fullline)) sourceWords [1 ..]
-- comments stripping
stripslcomments :: [[Token]] -> [[Token]]
stripslcomments = let f (NewLine _ : Token ('-':'-':_) _ : _) = False
f _ = True
isCmt (Token ('-':'-':_) _) = True
isCmt _ = False
in map (takeWhile (not . isCmt)) . filter f
stripblockcomments :: [Token] -> [Token]
stripblockcomments (Token "{-" pos : xs) =
trace_ "{- found at " (show pos) $
afterblockcomend xs
stripblockcomments (x:xs) = x:stripblockcomments xs
stripblockcomments [] = []
afterblockcomend :: [Token] -> [Token]
afterblockcomend (t@(Token _ pos):xs)
| contains "-}" (tokenString t) =
trace_ "-} found at " (show pos) $
stripblockcomments xs
| otherwise = afterblockcomend xs
afterblockcomend [] = []
afterblockcomend (_:xs) = afterblockcomend xs
-- does one string contain another string
contains :: Eq a => [a] -> [a] -> Bool
contains sub = any (isPrefixOf sub) . tails
-- actually pick up definitions
findstuff :: [Token] -> Scope -> [FoundThing]
findstuff (Token "module" _ : Token name pos : _) _ =
trace_ "module" pos [FoundThing FTModule name pos] -- nothing will follow this section
findstuff tokens@(Token "data" _ : Token name pos : xs) _
| any ( (== "where"). tokenString ) xs -- GADT
-- TODO will be found as FTCons (not FTConsGADT), the same for
-- functions - but they are found :)
=
trace_ "findstuff data b1" tokens $
FoundThing FTDataGADT name pos
: getcons2 (FTConsGADT name) "" xs ++ fromWhereOn xs Nothing -- ++ (findstuff xs)
| otherwise
=
trace_ "findstuff data otherwise" tokens $
FoundThing FTData name pos
: getcons (FTCons FTData name) (trimNewlines xs)-- ++ (findstuff xs)
findstuff tokens@(Token "newtype" _ : ts@(Token name pos : _))_ =
trace_ "findstuff newtype" tokens $
FoundThing FTNewtype name pos
: getcons (FTCons FTNewtype name) (trimNewlines ts)-- ++ (findstuff xs)
-- FoundThing FTNewtype name pos : findstuff xs
findstuff tokens@(Token "type" _ : Token name pos : xs) _ =
trace_ "findstuff type" tokens $
case break ((== "where").tokenString) xs of
(ys, []) ->
trace_ "findstuff type b1 " ys [FoundThing FTType name pos]
(ys, r) ->
trace_ "findstuff type b2 " (ys, r) $
FoundThing FTType name pos : fromWhereOn r Nothing
findstuff tokens@(Token "class" _ : xs) _ =
trace_ "findstuff class" tokens $
case break ((== "where").tokenString) xs of
(ys, []) ->
trace_ "findstuff class b1 " ys $
maybeToList $ className ys
(ys, r) ->
trace_ "findstuff class b2 " (ys, r) $
maybe [] (\n@(FoundThing _ name _) -> n : fromWhereOn r (Just (FTClass, name))) $
className ys
where isParenOpen (Token "(" _) = True
isParenOpen _ = False
className lst
= case (head'
. dropWhile isParenOpen
. reverse
. takeWhile ((not . (`elem` ["=>", utf8_to_char8_hack "⇒"])) . tokenString)
. reverse) lst of
(Just (Token name p)) -> Just $ FoundThing FTClass name p
_ -> Nothing
findstuff tokens@(Token "instance" _ : xs) _ =
trace_ "findstuff instance" tokens $
case break ((== "where").tokenString) xs of
(ys, []) ->
trace_ "findstuff instance b1 " ys $
maybeToList $ instanceName ys
(ys, r) ->
trace_ "findstuff instance b2 " (ys, r) $
maybe [] (\n@(FoundThing _ name _) -> n : fromWhereOn r (Just (FTInstance, name))) $
instanceName ys
where instanceName lst@(Token _ p :_) = Just $ FoundThing FTInstance
(map (\a -> if a == '.' then '-' else a) $ concatTokens lst) p
instanceName _ = Nothing
findstuff tokens@(Token "pattern" _ : Token name pos : Token "::" _ : sig) _ =
trace_ "findstuff pattern type annotation" tokens [FoundThing (FTPatternTypeDef (concatTokens sig)) name pos]
findstuff tokens@(Token "pattern" _ : Token name pos : xs) scope =
trace_ "findstuff pattern" tokens $
FoundThing FTPattern name pos : findstuff xs scope
findstuff xs scope =
trace_ "findstuff rest " xs $
findFunc xs scope ++ findFuncTypeDefs [] xs scope
findFuncTypeDefs :: [Token] -> [Token] -> Scope -> [FoundThing]
findFuncTypeDefs found (t@(Token _ _): Token "," _ :xs) scope =
findFuncTypeDefs (t : found) xs scope
findFuncTypeDefs found (t@(Token _ _): Token "::" _ : sig) scope =
map (\(Token name p) -> FoundThing (FTFuncTypeDef (concatTokens sig) scope) name p) (t:found)
findFuncTypeDefs found xs@(Token "(" _ :_) scope =
case break myBreakF xs of
(inner@(Token _ p : _), rp : xs') ->
let merged = Token ( concatMap (\z -> case z of
(Token x _) -> x
(NewLine _) -> "")
$ inner ++ [rp] ) p
in findFuncTypeDefs found (merged : xs') scope
_ -> []
where myBreakF (Token ")" _) = True
myBreakF _ = False
findFuncTypeDefs _ _ _ = []
fromWhereOn :: [Token] -> Scope -> [FoundThing]
fromWhereOn [] _ = []
fromWhereOn [_] _ = []
fromWhereOn (_: xs@(NewLine _ : _)) scope =
concatMap (flip findstuff scope . tail')
$ splitByNL (Just ( minimum
. (10000:)
. map (\(NewLine i) -> i)
. filter (isNewLine Nothing) $ xs)) xs
fromWhereOn (_:xw) scope = findstuff xw scope
findFunc :: [Token] -> Scope -> [FoundThing]
findFunc x scope = case findInfix x scope of
a@(_:_) -> a
_ -> findF x scope
findInfix :: [Token] -> Scope -> [FoundThing]
findInfix x scope
= case dropWhile
((/= "`"). tokenString)
(takeWhile ( (/= "=") . tokenString) x) of
_ : Token name p : _ -> [FoundThing (FTFuncImpl scope) name p]
_ -> []
findF :: [Token] -> Scope -> [FoundThing]
findF ts@(Token "(" p : _) scope =
let (name, xs) = extractOperator ts in
[FoundThing (FTFuncImpl scope) name p | any (("=" ==) . tokenString) xs]
findF (Token name p : xs) scope =
[FoundThing (FTFuncImpl scope) name p | any (("=" ==) . tokenString) xs]
findF _ _ = []
head' :: [a] -> Maybe a
head' (x:_) = Just x
head' [] = Nothing
tail' :: [a] -> [a]
tail' (_:xs) = xs
tail' [] = []
-- get the constructor definitions, knowing that a datatype has just started
getcons :: FoundThingType -> [Token] -> [FoundThing]
getcons ftt (Token "=" _: Token name pos : xs) =
FoundThing ftt name pos : getcons2 ftt name xs
getcons ftt (_:xs) = getcons ftt xs
getcons _ [] = []
getcons2 :: FoundThingType -> String -> [Token] -> [FoundThing]
getcons2 ftt@(FTCons pt p) c (Token name pos : Token "::" _ : xs) =
FoundThing (FTConsAccessor pt p c) name pos : getcons2 ftt c xs
getcons2 ftt@(FTConsGADT p) _ (Token name pos : Token "::" _ : xs) =
FoundThing ftt name pos : getcons2 ftt p xs
getcons2 ftt _ (Token "|" _ : Token name pos : xs) =
FoundThing ftt name pos : getcons2 ftt name xs
getcons2 ftt c (_:xs) = getcons2 ftt c xs
getcons2 _ _ [] = []
splitByNL :: Maybe Int -> [Token] -> [[Token]]
splitByNL maybeIndent (nl@(NewLine _):ts) =
let (a,b) = break (isNewLine maybeIndent) ts
in (nl : a) : splitByNL maybeIndent b
splitByNL _ _ = []
-- this only exists for test case testcases/HUnitBase.lhs (bird literate haskell style)
getTopLevelIndent :: Bool -> [[Token]] -> Int
getTopLevelIndent _ [] = 0 -- (no import found, assuming indent 0: this can be
-- done better but should suffice for most needs
getTopLevelIndent isLiterate ((nl:next:_):xs) = if "import" == tokenString next
then let (NewLine i) = nl in i
else getTopLevelIndent isLiterate xs
getTopLevelIndent isLiterate (_:xs) = getTopLevelIndent isLiterate xs
-- According to http://www.haskell.org/onlinereport/literate.html either
-- birdstyle or LaTeX style should be used. However simple experiments show
-- that unlit distributed by GHC has the following behavior
-- * The space after ">" can be omitted
-- * ">" must be first char in line to be read as birdstyle (then its replaced by a space)
-- * \begin{code} gets recognized if its indented, but \end{code} does not (?)
--
-- Attention: Base.lhs (shipping with GHC) have birdstyle in block comments
fromLiterate :: FilePath -> [(String, Int)]
-> (Bool -- is literate
, [(String, Int)])
fromLiterate file lns =
if ".lhs" `isSuffixOf` file
then (True, unlit lns)
else (False, lns)
where unlit, returnCode :: [(String, Int)] -> [(String, Int)]
unlit (('>':' ':xs,n):ns) = (' ':xs,n):unlit ns -- unlit keeps space, so do we
unlit ((line,_):ns) = if "\\begin{code}" `isPrefixOf` line then returnCode ns else unlit ns
unlit [] = []
-- in \begin{code} block
returnCode (t@(line,_):ns) = if "\\end{code}" `isPrefixOf` line then unlit ns else t:returnCode ns
returnCode [] = [] -- unexpected - hasktags does tagging, not compiling, thus don't treat missing \end{code} to be an error
-- suffixes: [".hs",".lhs"], use "" to match all files
dirToFiles :: Bool -> [String] -> FilePath -> IO [ FilePath ]
dirToFiles _ _ "STDIN" = lines <$> getContents
dirToFiles followSyms suffixes p = do
isD <- doesDirectoryExist p
#if MIN_VERSION_directory(1,3,0)
isSymLink <- pathIsSymbolicLink p
#else
isSymLink <- isSymbolicLink p
#endif
if isD
then if isSymLink && not followSyms
then return []
else do
-- filter . .. and hidden files .*
contents <- filter ((/=) '.' . head) `fmap` getDirectoryContents p
concat `fmap` mapM (dirToFiles followSyms suffixes . (</>) p) contents
else return [p | matchingSuffix ]
where matchingSuffix = any (`isSuffixOf` p) suffixes
concatTokens :: [Token] -> String
concatTokens = smartUnwords . map (\(Token name _) -> name) . filter (not . isNewLine Nothing)
where smartUnwords [] = []
smartUnwords a = foldr (\v -> (glueNext v ++)) "" $ a `zip` tail (a ++ [""])
glueNext (a@("("), _) = a
glueNext (a, ")") = a
glueNext (a@("["), _) = a
glueNext (a, "]") = a
glueNext (a, ",") = a
glueNext (a, "") = a
glueNext (a, _) = a ++ " "
extractOperator :: [Token] -> (String, [Token])
extractOperator ts@(Token "(" _ : _) =
foldr ((++) . tokenString) ")" *** tail $ break ((== ")") . tokenString) ts
extractOperator _ = ("", [])