Improve debug logging for stack build (#2348)

src/Stack/Build.hs

@@ -161,7 +161,8 @@ instance Exception CabalVersionException
 -- | See https://github.com/commercialhaskell/stack/issues/1198.
 warnIfExecutablesWithSameNameCouldBeOverwritten
     :: MonadLogger m => [LocalPackage] -> Plan -> m ()
-warnIfExecutablesWithSameNameCouldBeOverwritten locals plan =
+warnIfExecutablesWithSameNameCouldBeOverwritten locals plan = do
+    $logDebug "Checking if we are going to build multiple executables with the same name"
     forM_ (Map.toList warnings) $ \(exe,(toBuild,otherLocals)) -> do
         let exe_s
                 | length toBuild > 1 = "several executables with the same name:"

src/Stack/Build/ConstructPlan.hs

@@ -135,6 +135,7 @@ constructPlan :: forall env m.
               -> InstalledMap
               -> m Plan
 constructPlan mbp0 baseConfigOpts0 locals extraToBuild0 localDumpPkgs loadPackage0 sourceMap installedMap = do
+    $logDebug "Constructing the build plan"
     let locallyRegistered = Map.fromList $ map (dpGhcPkgId &&& dpPackageIdent) localDumpPkgs
     getVersions0 <- getPackageVersionsIO
 

src/Stack/Build/Execute.hs

@@ -348,6 +348,7 @@ executePlan :: M env m
             -> Plan
             -> m ()
 executePlan menv boptsCli baseConfigOpts locals globalPackages snapshotPackages localPackages installedMap targets plan = do
+    $logDebug "Executing the build plan"
     bopts <- asks (configBuild . getConfig)
     withExecuteEnv menv bopts boptsCli baseConfigOpts locals globalPackages snapshotPackages localPackages (executePlan' installedMap targets plan)
 

src/Stack/Build/Installed.hs

@@ -64,6 +64,7 @@ getInstalled :: (M env m, PackageInstallInfo pii)
                   , [DumpPackage () ()] -- locally installed
                   )
 getInstalled menv opts sourceMap = do
+    $logDebug "Finding out which packages are already installed"
     snapDBPath <- packageDatabaseDeps
     localDBPath <- packageDatabaseLocal
     extraDBPaths <- packageDatabaseExtra

src/Stack/Build/Source.hs

@@ -195,6 +195,7 @@ parseTargetsFromBuildOpts
     -> BuildOptsCLI
     -> m (MiniBuildPlan, M.Map PackageName Version, M.Map PackageName SimpleTarget)
 parseTargetsFromBuildOpts needTargets boptscli = do
+    $logDebug "Parsing the targets"
     bconfig <- asks getBuildConfig
     mbp0 <-
         case bcResolver bconfig of
@@ -258,6 +259,7 @@ convertSnapshotToExtra snapshot extra0 locals = go Map.empty
 getLocalPackageViews :: (MonadThrow m, MonadIO m, MonadReader env m, HasEnvConfig env, MonadLogger m)
                      => m (Map PackageName (LocalPackageView, GenericPackageDescription))
 getLocalPackageViews = do
+    $logDebug "Parsing the cabal files of the local packages"
     econfig <- asks getEnvConfig
     locals <- forM (Map.toList $ envConfigPackages econfig) $ \(dir, treatLikeExtraDep) -> do
         cabalfp <- findOrGenerateCabalFile dir

src/main/Main.hs

@@ -919,6 +919,7 @@ withBuildConfigExt go@GlobalOpts{..} mbefore inner mafter = do
                withUserFileLock go dir $ \lk2 -> do
                  liftIO $ writeIORef curLk lk2
                  liftIO $ munlockFile lk
+                 $logDebug "Starting to execute command inside EnvConfig"
                  inner lk2
 
       let inner'' lk = do