summaryrefslogtreecommitdiff
path: root/src/Language/PureScript/Make/BuildPlan.hs
blob: ebbe50d645275f3e97c2d4f5c6c0f9a57a5f5e48 (plain)
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
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
module Language.PureScript.Make.BuildPlan
  ( BuildPlan()
  , BuildJobResult(..)
  , buildJobSuccess
  , buildJobFailure
  , construct
  , getResult
  , collectResults
  , markComplete
  , needsRebuild
  ) where

import           Prelude

import           Control.Concurrent.Async.Lifted as A
import           Control.Concurrent.Lifted as C
import           Control.Monad hiding (sequence)
import           Control.Monad.Trans.Control (MonadBaseControl(..))
import           Control.Monad.Trans.Maybe (MaybeT(..), runMaybeT)
import           Data.Foldable (foldl')
import qualified Data.Map as M
import           Data.Maybe (fromMaybe, mapMaybe)
import           Data.Time.Clock (UTCTime)
import           Language.PureScript.AST
import           Language.PureScript.Crash
import qualified Language.PureScript.CST as CST
import           Language.PureScript.Errors
import           Language.PureScript.Externs
import           Language.PureScript.Make.Actions as Actions
import           Language.PureScript.Make.Cache
import           Language.PureScript.Names (ModuleName)

-- | The BuildPlan tracks information about our build progress, and holds all
-- prebuilt modules for incremental builds.
data BuildPlan = BuildPlan
  { bpPrebuilt :: M.Map ModuleName Prebuilt
  , bpBuildJobs :: M.Map ModuleName BuildJob
  }

data Prebuilt = Prebuilt
  { pbModificationTime :: UTCTime
  , pbExternsFile :: ExternsFile
  }

newtype BuildJob = BuildJob
  { bjResult :: C.MVar BuildJobResult
    -- ^ Note: an empty MVar indicates that the build job has not yet finished.
  }

data BuildJobResult
  = BuildJobSucceeded !MultipleErrors !ExternsFile
  -- ^ Succeeded, with warnings and externs
  --
  | BuildJobFailed !MultipleErrors
  -- ^ Failed, with errors

  | BuildJobSkipped
  -- ^ The build job was not run, because an upstream build job failed

buildJobSuccess :: BuildJobResult -> Maybe (MultipleErrors, ExternsFile)
buildJobSuccess (BuildJobSucceeded warnings externs) = Just (warnings, externs)
buildJobSuccess _ = Nothing

buildJobFailure :: BuildJobResult -> Maybe MultipleErrors
buildJobFailure (BuildJobFailed errors) = Just errors
buildJobFailure _ = Nothing

-- | Information obtained about a particular module while constructing a build
-- plan; used to decide whether a module needs rebuilding.
data RebuildStatus = RebuildStatus
  { statusModuleName :: ModuleName
  , statusRebuildNever :: Bool
  , statusNewCacheInfo :: Maybe CacheInfo
    -- ^ New cache info for this module which should be stored for subsequent
    -- incremental builds. A value of Nothing indicates that cache info for
    -- this module should not be stored in the build cache, because it is being
    -- rebuilt according to a RebuildPolicy instead.
  , statusPrebuilt :: Maybe Prebuilt
    -- ^ Prebuilt externs and timestamp for this module, if any.
  }

-- | Called when we finished compiling a module and want to report back the
-- compilation result, as well as any potential errors that were thrown.
markComplete
  :: (MonadBaseControl IO m)
  => BuildPlan
  -> ModuleName
  -> BuildJobResult
  -> m ()
markComplete buildPlan moduleName result = do
  let BuildJob rVar = fromMaybe (internalError "make: markComplete no barrier") $ M.lookup moduleName (bpBuildJobs buildPlan)
  putMVar rVar result

-- | Whether or not the module with the given ModuleName needs to be rebuilt
needsRebuild :: BuildPlan -> ModuleName -> Bool
needsRebuild bp moduleName = M.member moduleName (bpBuildJobs bp)

-- | Collects results for all prebuilt as well as rebuilt modules. This will
-- block until all build jobs are finished. Prebuilt modules always return no
-- warnings.
collectResults
  :: (MonadBaseControl IO m)
  => BuildPlan
  -> m (M.Map ModuleName BuildJobResult)
collectResults buildPlan = do
  let prebuiltResults = M.map (BuildJobSucceeded (MultipleErrors []) . pbExternsFile) (bpPrebuilt buildPlan)
  barrierResults <- traverse (readMVar . bjResult) $ bpBuildJobs buildPlan
  pure (M.union prebuiltResults barrierResults)

-- | Gets the the build result for a given module name independent of whether it
-- was rebuilt or prebuilt. Prebuilt modules always return no warnings.
getResult
  :: (MonadBaseControl IO m)
  => BuildPlan
  -> ModuleName
  -> m (Maybe (MultipleErrors, ExternsFile))
getResult buildPlan moduleName =
  case M.lookup moduleName (bpPrebuilt buildPlan) of
    Just es ->
      pure (Just (MultipleErrors [], pbExternsFile es))
    Nothing -> do
      r <- readMVar $ bjResult $ fromMaybe (internalError "make: no barrier") $ M.lookup moduleName (bpBuildJobs buildPlan)
      pure $ buildJobSuccess r

-- | Constructs a BuildPlan for the given module graph.
--
-- The given MakeActions are used to collect various timestamps in order to
-- determine whether a module needs rebuilding.
construct
  :: forall m. (Monad m, MonadBaseControl IO m)
  => MakeActions m
  -> CacheDb
  -> ([CST.PartialResult Module], [(ModuleName, [ModuleName])])
  -> m (BuildPlan, CacheDb)
construct MakeActions{..} cacheDb (sorted, graph) = do
  let sortedModuleNames = map (getModuleName . CST.resPartial) sorted
  rebuildStatuses <- A.forConcurrently sortedModuleNames getRebuildStatus
  let prebuilt =
        foldl' collectPrebuiltModules M.empty $
          mapMaybe (\s -> (statusModuleName s, statusRebuildNever s,) <$> statusPrebuilt s) rebuildStatuses
  let toBeRebuilt = filter (not . flip M.member prebuilt) sortedModuleNames
  buildJobs <- foldM makeBuildJob M.empty toBeRebuilt
  pure
    ( BuildPlan prebuilt buildJobs
    , let
        update = flip $ \s ->
          M.alter (const (statusNewCacheInfo s)) (statusModuleName s)
      in
        foldl' update cacheDb rebuildStatuses
    )
  where
    makeBuildJob prev moduleName = do
      buildJob <- BuildJob <$> C.newEmptyMVar
      pure (M.insert moduleName buildJob prev)

    getRebuildStatus :: ModuleName -> m RebuildStatus
    getRebuildStatus moduleName = do
      inputInfo <- getInputTimestampsAndHashes moduleName
      case inputInfo of
        Left RebuildNever -> do
          prebuilt <- findExistingExtern moduleName
          pure (RebuildStatus
            { statusModuleName = moduleName
            , statusRebuildNever = True
            , statusPrebuilt = prebuilt
            , statusNewCacheInfo = Nothing
            })
        Left RebuildAlways -> do
          pure (RebuildStatus
            { statusModuleName = moduleName
            , statusRebuildNever = False
            , statusPrebuilt = Nothing
            , statusNewCacheInfo = Nothing
            })
        Right cacheInfo -> do
          (newCacheInfo, isUpToDate) <- checkChanged cacheDb moduleName cacheInfo
          prebuilt <-
            if isUpToDate
              then findExistingExtern moduleName
              else pure Nothing
          pure (RebuildStatus
            { statusModuleName = moduleName
            , statusRebuildNever = False
            , statusPrebuilt = prebuilt
            , statusNewCacheInfo = Just newCacheInfo
            })

    findExistingExtern :: ModuleName -> m (Maybe Prebuilt)
    findExistingExtern moduleName = runMaybeT $ do
      timestamp <- MaybeT $ getOutputTimestamp moduleName
      externs <- MaybeT $ decodeExterns . snd <$> readExterns moduleName
      pure (Prebuilt timestamp externs)

    collectPrebuiltModules :: M.Map ModuleName Prebuilt -> (ModuleName, Bool, Prebuilt) -> M.Map ModuleName Prebuilt
    collectPrebuiltModules prev (moduleName, rebuildNever, pb)
      | rebuildNever = M.insert moduleName pb prev
      | otherwise = do
          let deps = fromMaybe (internalError "make: module not found in dependency graph.") (lookup moduleName graph)
          case traverse (fmap pbModificationTime . flip M.lookup prev) deps of
            Nothing ->
              -- If we end up here, one of the dependencies didn't exist in the
              -- prebuilt map and so we know a dependency needs to be rebuilt, which
              -- means we need to be rebuilt in turn.
              prev
            Just modTimes ->
              case maximumMaybe modTimes of
                Just depModTime | pbModificationTime pb < depModTime ->
                  prev
                _ -> M.insert moduleName pb prev

maximumMaybe :: Ord a => [a] -> Maybe a
maximumMaybe [] = Nothing
maximumMaybe xs = Just $ maximum xs