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
192
|
{- git branch stuff
-
- Copyright 2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE BangPatterns #-}
module Git.Branch where
import Common
import Git
import Git.Sha
import Git.Command
import qualified Git.Ref
{- The currently checked out branch.
-
- In a just initialized git repo before the first commit,
- symbolic-ref will show the master branch, even though that
- branch is not created yet. So, this also looks at show-ref HEAD
- to double-check.
-}
current :: Repo -> IO (Maybe Git.Ref)
current r = do
v <- currentUnsafe r
case v of
Nothing -> return Nothing
Just branch ->
ifM (null <$> pipeReadStrict [Param "show-ref", Param $ fromRef branch] r)
( return Nothing
, return v
)
{- The current branch, which may not really exist yet. -}
currentUnsafe :: Repo -> IO (Maybe Git.Ref)
currentUnsafe r = parse . firstLine
<$> pipeReadStrict [Param "symbolic-ref", Param $ fromRef Git.Ref.headRef] r
where
parse l
| null l = Nothing
| otherwise = Just $ Git.Ref l
{- Checks if the second branch has any commits not present on the first
- branch. -}
changed :: Branch -> Branch -> Repo -> IO Bool
changed origbranch newbranch repo
| origbranch == newbranch = return False
| otherwise = not . null <$> diffs
where
diffs = pipeReadStrict
[ Param "log"
, Param (fromRef origbranch ++ ".." ++ fromRef newbranch)
, Param "-n1"
, Param "--pretty=%H"
] repo
{- Check if it's possible to fast-forward from the old
- ref to the new ref.
-
- This requires there to be a path from the old to the new. -}
fastForwardable :: Ref -> Ref -> Repo -> IO Bool
fastForwardable old new repo = not . null <$>
pipeReadStrict
[ Param "log"
, Param $ fromRef old ++ ".." ++ fromRef new
, Param "-n1"
, Param "--pretty=%H"
, Param "--ancestry-path"
] repo
{- Given a set of refs that are all known to have commits not
- on the branch, tries to update the branch by a fast-forward.
-
- In order for that to be possible, one of the refs must contain
- every commit present in all the other refs.
-}
fastForward :: Branch -> [Ref] -> Repo -> IO Bool
fastForward _ [] _ = return True
fastForward branch (first:rest) repo =
-- First, check that the branch does not contain any
-- new commits that are not in the first ref. If it does,
-- cannot fast-forward.
ifM (changed first branch repo)
( no_ff
, maybe no_ff do_ff =<< findbest first rest
)
where
no_ff = return False
do_ff to = do
update branch to repo
return True
findbest c [] = return $ Just c
findbest c (r:rs)
| c == r = findbest c rs
| otherwise = do
better <- changed c r repo
worse <- changed r c repo
case (better, worse) of
(True, True) -> return Nothing -- divergent fail
(True, False) -> findbest r rs -- better
(False, True) -> findbest c rs -- worse
(False, False) -> findbest c rs -- same
{- The user may have set commit.gpgsign, indending all their manual
- commits to be signed. But signing automatic/background commits could
- easily lead to unwanted gpg prompts or failures.
-}
data CommitMode = ManualCommit | AutomaticCommit
deriving (Eq)
{- Commit via the usual git command. -}
commitCommand :: CommitMode -> [CommandParam] -> Repo -> IO Bool
commitCommand = commitCommand' runBool
{- Commit will fail when the tree is clean. This suppresses that error. -}
commitQuiet :: CommitMode -> [CommandParam] -> Repo -> IO ()
commitQuiet commitmode ps = void . tryIO . commitCommand' runQuiet commitmode ps
commitCommand' :: ([CommandParam] -> Repo -> IO a) -> CommitMode -> [CommandParam] -> Repo -> IO a
commitCommand' runner commitmode ps = runner (Param "commit" : ps')
where
ps'
| commitmode == AutomaticCommit = Param "--no-gpg-sign" : ps
| otherwise = ps
{- Commits the index into the specified branch (or other ref),
- with the specified parent refs, and returns the committed sha.
-
- Without allowempy set, avoids making a commit if there is exactly
- one parent, and it has the same tree that would be committed.
-
- Unlike git-commit, does not run any hooks, or examine the work tree
- in any way.
-}
commit :: CommitMode -> Bool -> String -> Branch -> [Ref] -> Repo -> IO (Maybe Sha)
commit commitmode allowempty message branch parentrefs repo = do
tree <- getSha "write-tree" $
pipeReadStrict [Param "write-tree"] repo
ifM (cancommit tree)
( do
sha <- getSha "commit-tree" $ pipeWriteRead
(map Param $ ["commit-tree", fromRef tree] ++ ps)
(Just $ flip hPutStr message) repo
update branch sha repo
return $ Just sha
, return Nothing
)
where
ps =
(if commitmode == AutomaticCommit then ["--no-gpg-sign"] else [])
++ concatMap (\r -> ["-p", fromRef r]) parentrefs
cancommit tree
| allowempty = return True
| otherwise = case parentrefs of
[p] -> maybe False (tree /=) <$> Git.Ref.tree p repo
_ -> return True
commitAlways :: CommitMode -> String -> Branch -> [Ref] -> Repo -> IO Sha
commitAlways commitmode message branch parentrefs repo = fromJust
<$> commit commitmode True message branch parentrefs repo
{- A leading + makes git-push force pushing a branch. -}
forcePush :: String -> String
forcePush b = "+" ++ b
{- Updates a branch (or other ref) to a new Sha. -}
update :: Branch -> Sha -> Repo -> IO ()
update branch sha = run
[ Param "update-ref"
, Param $ fromRef branch
, Param $ fromRef sha
]
{- Checks out a branch, creating it if necessary. -}
checkout :: Branch -> Repo -> IO ()
checkout branch = run
[ Param "checkout"
, Param "-q"
, Param "-B"
, Param $ fromRef $ Git.Ref.base branch
]
{- Removes a branch. -}
delete :: Branch -> Repo -> IO ()
delete branch = run
[ Param "branch"
, Param "-q"
, Param "-D"
, Param $ fromRef $ Git.Ref.base branch
]
|
