1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
{-# LANGUAGE RecordWildCards #-}
module Main where
import Control.Exception
import Control.Monad
import Data.Bool
import Data.Foldable
import Opts
import System.Exit
import System.FilePath
import System.IO
import System.IO.Temp
import System.Process
import qualified Toks
import Debug.Trace
-- TODO: the diff w
rundiff f1 f2 out = do
st <-
withFile out WriteMode $ \oh ->
withCreateProcess
(proc
"diff" -- TODO: from WERGE_DIFF env
[ "--text"
, "--new-line-format=+%L"
, "--old-line-format=-%L"
, "--unchanged-line-format= %L"
, f1
, f2
])
{std_in = NoStream, std_out = UseHandle oh, std_err = Inherit} $ \_ _ _ ->
waitForProcess
when (st == ExitFailure 2) $ error "diff failed"
unless (st `elem` [ExitSuccess, ExitFailure 1])
$ error "diff failed for unknown reason (is GNU diffutils installed?)"
data Op
= Del
| Keep
| Add
deriving (Show, Eq)
pdiff path = map go . lines <$> readFile path
where
go [] = error "empty line from diff"
go ('-':s) = (Del, s)
go (' ':s) = (Keep, s)
go ('+':s) = (Add, s)
data Merged
= Ok [String]
| Conflict [String] [String] [String]
deriving (Show)
align :: [(Op, String)] -> [(Op, String)] -> [Merged]
align [] [] = []
align ((Keep, m):ms) ((Keep, y):ys)
| m == y = Ok [m] : align ms ys
align ((Del, m):ms) ((Del, y):ys)
| m == y = Conflict [] [m] [] : align ms ys
align ((Del, m):ms) ((Keep, y):ys)
| m == y = Conflict [] [m] [m] : align ms ys
align ((Keep, m):ms) ((Del, y):ys)
| m == y = Conflict [m] [m] [] : align ms ys
align ((Add, m):ms) ys = Conflict [m] [] [] : align ms ys
align ms ((Add, y):ys) = Conflict [] [] [y] : align ms ys
align _ _ = error "diffs do not align"
regroup :: [Merged] -> [Merged]
regroup [] = []
regroup (Ok []:xs) = regroup xs
regroup (x@(Ok a):xs) =
case regroup xs of
(Ok b:xs') -> Ok (a ++ b) : xs'
xs' -> x : xs'
regroup (Conflict [] [] []:xs) = regroup xs
regroup (x@(Conflict m1 o1 y1):xs) =
case regroup xs of
(Conflict m2 o2 y2:xs') -> Conflict (m1 ++ m2) (o1 ++ o2) (y1 ++ y2) : xs'
xs' -> x : xs'
regroup (x:xs) = x : regroup xs
expand :: Int -> [Merged] -> [Merged]
expand n = go
where
go [] = []
go (x@(Conflict m1 o1 y1):xs) =
case go xs of
(Ok a:Conflict m2 o2 y2:xs')
| length a <= n ->
Conflict (m1 ++ a ++ m2) (o1 ++ a ++ o2) (y1 ++ a ++ y2) : xs'
xs' -> x : xs'
go (x:xs) = x : go xs
zeal (Conflict m o y) =
before' ++ (Conflict (reverse m'') o (reverse y'') : after')
where
((m', y'), before) = pops m y
((m'', y''), rafter) = pops (reverse m') (reverse y')
before' =
case before of
[] -> []
xs -> [Ok xs]
after' =
case rafter of
[] -> []
xs -> [Ok $ reverse xs]
pops (m:ms) (y:ys)
| m == y = (m :) <$> pops ms ys
pops ms ys = ((ms, ys), [])
zeal x = [x]
resolve cfg@Config {..} c@(Conflict m o y)
| all Toks.space (concat [m, o, y]) && cfgSpaces /= SpacesNormal =
resolveSpace cfg c
| m == o && o == y = Ok o
| m == o && cfgResolveSeparate = Ok y
| o == y && cfgResolveSeparate = Ok m
| m == y && cfgResolveOverlaps = Ok m
resolve _ x = x
-- TODO: there might be a bit of interplay between the spaces handling and
-- separate/overlapped conflict resolution -- e.g., what if someone wants to
-- merge overlapping edits in text but separate edits in spaces? At this point
-- that might be ignorable.
resolveSpace Config {..} c@(Conflict m o y)
| m == o && o == y = Ok o
| otherwise =
case cfgSpaces of
SpacesConflict -> c
SpacesMy -> Ok m
SpacesOld -> Ok o
SpacesYour -> Ok y
_ -> error "spaces resolution failed"
resolveSpaces _ x = x
merge cfg@Config {..} ms ys =
regroup
. map (resolve cfg)
. regroup
. bool id (concatMap zeal) cfgZealous
. expand cfgContext
. regroup
$ align ms ys
format :: Config -> [Merged] -> IO Bool
format Config {..} = go False
where
go c [] = pure c
go c (Ok x:xs) = do
putStr (Toks.glueToks x)
go c xs
go c (Conflict m o y:xs) = do
putStr
$ mconcat
[ cfgLabelStart
, Toks.glueToks m
, cfgLabelMyOld
, Toks.glueToks o
, cfgLabelOldYour
, Toks.glueToks y
, cfgLabelEnd
]
go True xs
runCmd CmdDiff3 {..} cfg =
withSystemTempDirectory "werge-diff3" $ \workdir -> do
let [fMy, fOld, fYour, fdMy, fdYour] =
map (workdir </>) ["my", "old", "your", "mydiff", "yourdiff"]
for_ [(d3my, fMy), (d3old, fOld), (d3your, fYour)] $ \(path, tmp) ->
readFile path >>= writeFile tmp . Toks.split -- TODO cfg
rundiff fOld fMy fdMy
rundiff fOld fYour fdYour
conflicted <- merge cfg <$> pdiff fdMy <*> pdiff fdYour >>= format cfg
if conflicted
then exitWith (ExitFailure 1)
else exitSuccess
runCmd _ _ = error "not implemented yet"
main :: IO ()
main = catch go bad
where
go = do
(cfg, cmd) <- parseOpts
runCmd cmd cfg
bad e = do
hPutStrLn stderr $ "fatal: " ++ displayException (e :: IOException)
exitWith (ExitFailure 2)
|
