+-- When a line number is specified, the current policy for choosing
+-- the best breakpoint is this:
+-- - the leftmost complete subexpression on the specified line, or
+-- - the leftmost subexpression starting on the specified line, or
+-- - the rightmost subexpression enclosing the specified line
+--
+findBreakByLine :: Int -> TickArray -> Maybe (BreakIndex,SrcSpan)
+findBreakByLine line arr
+ | not (inRange (bounds arr) line) = Nothing
+ | otherwise =
+ listToMaybe (sortBy leftmost complete) `mplus`
+ listToMaybe (sortBy leftmost incomplete) `mplus`
+ listToMaybe (sortBy rightmost ticks)
+ where
+ ticks = arr ! line
+
+ starts_here = [ tick | tick@(nm,span) <- ticks,
+ srcSpanStartLine span == line ]
+
+ (complete,incomplete) = partition ends_here starts_here
+ where ends_here (nm,span) = srcSpanEndLine span == line
+
+findBreakByCoord :: (Int,Int) -> TickArray -> Maybe (BreakIndex,SrcSpan)
+findBreakByCoord (line, col) arr
+ | not (inRange (bounds arr) line) = Nothing
+ | otherwise =
+ listToMaybe (sortBy rightmost contains)
+ where
+ ticks = arr ! line
+
+ -- the ticks that span this coordinate
+ contains = [ tick | tick@(nm,span) <- ticks, span `spans` (line,col) ]
+
+leftmost (_,a) (_,b) = a `compare` b
+rightmost (_,a) (_,b) = b `compare` a
+
+spans :: SrcSpan -> (Int,Int) -> Bool
+spans span (l,c) = srcSpanStart span <= loc && loc <= srcSpanEnd span
+ where loc = mkSrcLoc (srcSpanFile span) l c
+
+start_bold = BS.pack "\ESC[1m"
+end_bold = BS.pack "\ESC[0m"
+
+listCmd :: String -> GHCi ()
+listCmd str = do
+ st <- getGHCiState
+ case resume st of
+ [] -> printForUser $ text "not stopped at a breakpoint; nothing to list"
+ (span,_,_):_ -> io $ listAround span True
+
+-- | list a section of a source file around a particular SrcSpan.
+-- If the highlight flag is True, also highlight the span using
+-- start_bold/end_bold.
+listAround span do_highlight = do
+ contents <- BS.readFile (unpackFS file)
+ let
+ lines = BS.split '\n' contents
+ these_lines = take (line2 - line1 + 1 + 2*padding) $
+ drop (line1 - 1 - padding) $ lines
+ fst_line = max 1 (line1 - padding)
+ line_nos = [ fst_line .. ]
+
+ highlighted | do_highlight = zipWith highlight line_nos these_lines
+ | otherwise = these_lines
+
+ bs_line_nos = [ BS.pack (show l ++ " ") | l <- line_nos ]
+ prefixed = zipWith BS.append bs_line_nos highlighted
+ --
+ BS.putStrLn (BS.join (BS.pack "\n") prefixed)
+ where
+ file = srcSpanFile span
+ line1 = srcSpanStartLine span
+ col1 = srcSpanStartCol span
+ line2 = srcSpanEndLine span
+ col2 = srcSpanEndCol span
+ padding = 1
+
+ highlight no line
+ | no == line1 && no == line2
+ = let (a,r) = BS.splitAt col1 line
+ (b,c) = BS.splitAt (col2-col1) r
+ in
+ BS.concat [a,start_bold,b,end_bold,c]
+ | no == line1
+ = let (a,b) = BS.splitAt col1 line in
+ BS.concat [a, start_bold, b]
+ | no == line2
+ = let (a,b) = BS.splitAt col2 line in
+ BS.concat [a, end_bold, b]
+ | otherwise = line
+
+-- --------------------------------------------------------------------------
+-- Tick arrays
+
+getTickArray :: Module -> GHCi TickArray
+getTickArray modl = do
+ st <- getGHCiState
+ let arrmap = tickarrays st
+ case lookupModuleEnv arrmap modl of
+ Just arr -> return arr
+ Nothing -> do
+ (breakArray, ticks) <- getModBreak modl
+ let arr = mkTickArray (assocs ticks)
+ setGHCiState st{tickarrays = extendModuleEnv arrmap modl arr}
+ return arr
+
+discardTickArrays :: GHCi ()
+discardTickArrays = do
+ st <- getGHCiState
+ setGHCiState st{tickarrays = emptyModuleEnv}
+
+mkTickArray :: [(BreakIndex,SrcSpan)] -> TickArray
+mkTickArray ticks
+ = accumArray (flip (:)) [] (1, max_line)
+ [ (line, (nm,span)) | (nm,span) <- ticks,
+ line <- srcSpanLines span ]
+ where
+ max_line = maximum (map srcSpanEndLine (map snd ticks))
+ srcSpanLines span = [ srcSpanStartLine span .. srcSpanEndLine span ]
+
+getModBreak :: Module -> GHCi (GHC.BreakArray, Array Int SrcSpan)
projects / ghc-hetmet.git / blobdiff