Add simple verbose mode (-v) for debugging

Stackage/CompleteBuild.hs

@@ -30,6 +30,7 @@ data BuildFlags = BuildFlags
     { bfEnableTests      :: !Bool
     , bfDoUpload         :: !Bool
     , bfEnableLibProfile :: !Bool
+    , bfVerbose          :: !Bool
     } deriving (Show)
 
 data BuildType = Nightly | LTS BumpType
@@ -182,6 +183,7 @@ completeBuild buildType buildFlags = withManager tlsManagerSettings $ \man -> do
             , pbGlobalInstall = False
             , pbEnableTests = bfEnableTests buildFlags
             , pbEnableLibProfiling = bfEnableLibProfile buildFlags
+            , pbVerbose = bfVerbose buildFlags
             }
     performBuild pb >>= mapM_ putStrLn
 

Stackage/PerformBuild.hs

@@ -63,6 +63,7 @@ data PerformBuild = PerformBuild
     -- ^ Register packages in the global database
     , pbEnableTests        :: Bool
     , pbEnableLibProfiling :: Bool
+    , pbVerbose            :: Bool
     }
 
 data PackageInfo = PackageInfo
@@ -316,7 +317,8 @@ singleBuild pb@PerformBuild {..} SingleBuild {..} =
     PackageConstraints {..} = ppConstraints $ piPlan sbPackageInfo
 
     buildLibrary = wf libOut $ \outH -> do
-        let run = runChild outH
+        let run a b = do when pbVerbose $ log' (unwords (a : b))
+                         runChild outH a b
         log' $ "Unpacking " ++ namever
         runParent outH "cabal" ["unpack", namever]
 

app/stackage.hs

@@ -69,4 +69,7 @@ main =
                   help "Skip uploading bundle, docs, etc.")) <*>
         switch
             (long "enable-library-profiling" <>
-             help "Enable profiling when building")
+             help "Enable profiling when building") <*>
+        switch
+            (long "verbose" <> short 'v' <>
+             help "Output verbose detail about the build steps")