Make gitCheckout just an Action, no additional rule

This avoids some boiler plate and works just the same.

app/Foliage/CmdBuild.hs

@@ -23,7 +23,6 @@ import Distribution.Package
 import Distribution.Pretty (prettyShow)
 import Distribution.Version
 import Foliage.FetchURL (addFetchURLRule)
-import Foliage.GitClone (addGitCloneRule)
 import Foliage.HackageSecurity hiding (ToJSON, toJSON)
 import Foliage.Meta
 import Foliage.Meta.Aeson ()
@@ -43,7 +42,6 @@ cmdBuild buildOptions = do
   shake opts $
     do
       addFetchURLRule cacheDir
-      addGitCloneRule cacheDir
       addPrepareSourceRule (buildOptsInputDir buildOptions) cacheDir
       addPrepareSdistRule outputDirRoot
       phony "buildAction" (buildAction buildOptions)

app/Foliage/PrepareSource.hs

@@ -15,7 +15,6 @@ import Distribution.Pretty (prettyShow)
 import Distribution.Types.PackageId
 import Distribution.Types.PackageName (unPackageName)
 import Foliage.FetchURL (fetchURL)
-import Foliage.GitClone (gitClone)
 import Foliage.Meta
 import Foliage.UpdateCabalFile (rewritePackageVersion)
 import GHC.Generics
@@ -70,8 +69,8 @@ addPrepareSourceRule inputDir cacheDir = addBuiltinRule noLint noIdentity run
             tarballPath <- fetchURL uri
             extractFromTarball tarballPath mSubdir srcDir
           GitHubSource repo rev mSubdir -> do
-            workDir <- gitClone repo rev
-            let packageDir = maybe workDir (workDir </>) mSubdir
+            workingCopy <- gitCheckout cacheDir repo rev
+            let packageDir = maybe workingCopy (workingCopy </>) mSubdir
             copyDirectoryContents packageDir srcDir
 
         let patchesDir = inputDir </> unPackageName pkgName </> prettyShow pkgVersion </> "patches"
@@ -120,6 +119,20 @@ addPrepareSourceRule inputDir cacheDir = addBuiltinRule noLint noIdentity run
 
       copyDirectoryContents srcDir outDir
 
+gitCheckout :: FilePath -> GitHubRepo -> GitHubRev -> Action FilePath
+gitCheckout cacheDir repo rev = do
+  alreadyCloned <- doesDirectoryExist path
+  if alreadyCloned
+    then command_ [Cwd path] "git" ["fetch"]
+    else command_ [] "git" ["clone", "--recursive", url, path]
+  command_ [Cwd path] "git" ["checkout", show rev]
+  command_ [Cwd path] "git" ["submodule", "update"]
+  pure path
+ where
+  path = cacheDir </> "git" </> show repo
+
+  url = "https://github.com/" <> show repo <> ".git"
+
 copyDirectoryContents :: FilePath -> FilePath -> Action ()
 copyDirectoryContents source destination =
   cmd_

foliage.cabal

@@ -27,7 +27,6 @@ executable foliage
         Foliage.CmdCreateKeys
         Foliage.CmdImportIndex
         Foliage.FetchURL
-        Foliage.GitClone
         Foliage.HackageSecurity
         Foliage.Meta
         Foliage.Meta.Aeson

tests/Tests.hs

@@ -40,6 +40,10 @@ main = do
           inTemporaryDirectoryWithFixture "tests/fixtures/git-submodule" $ do
             step "Building repository"
             callCommand "foliage build"
+
+            doesFileExist "_cache/git/cardano-scaling/foliage-test-with-submodule/README.md" @? "Missing working copy"
+            doesFileExist "_cache/foliage-test-with-submodule/1.0.0/README.md" @? "Missing packaged version"
+            doesFileExist "_cache/foliage-test-with-submodule/1.1.0/README.md" @? "Missing packaged version"
       , ---
         testCaseSteps "accepts --no-signatures" $ \step ->
           inTemporaryDirectoryWithFixture "tests/fixtures/simple" $ do