chore: only build files tracked by git

support/shake/app/Shake/Git.hs

@@ -1,7 +1,8 @@
 {-# LANGUAGE BlockArguments, GeneralizedNewtypeDeriving, TypeFamilies #-}
 
 module Shake.Git
-  ( gitCommit
+  ( gitFiles
+  , gitCommit
   , gitAuthors
   , gitRules
   ) where
@@ -22,6 +23,15 @@ import Development.Shake
 gitCommand :: CmdResult r => [String] -> Action r
 gitCommand args = command [] "git" (["--git-dir", ".git"] ++ args)
 
+newtype GitFiles = GitFiles ()
+  deriving (Show, Typeable, Eq, Hashable, Binary, NFData)
+
+type instance RuleResult GitFiles = [FilePath]
+
+-- | Get the list of files tracked by git.
+gitFiles :: Action [FilePath]
+gitFiles = askOracle (GitFiles ())
+
 newtype GitCommit = GitCommit ()
   deriving (Show, Typeable, Eq, Hashable, Binary, NFData)
 
@@ -62,6 +72,10 @@ doGitAuthors (GitAuthors path) = do
 -- | Shake rules required for reading Git information.
 gitRules :: Rules()
 gitRules = versioned 1 do
+  _ <- addOracle \(GitFiles ()) -> do
+    Stdout t <- gitCommand ["ls-files", "--full-name"]
+    pure (lines t)
+
   _ <- addOracle \(GitCommit ()) -> do
     Stdout t <- gitCommand ["rev-parse", "--verify", "HEAD"]
     pure (head (lines t))

support/shake/app/Shake/Modules.hs

@@ -20,6 +20,8 @@ import GHC.Generics (Generic)
 
 import HTML.Backend (moduleName)
 
+import Shake.Git
+
 type ModName = String
 
 data ModulesQ = ModulesQ
@@ -55,11 +57,13 @@ moduleRules :: Rules ()
 moduleRules = do
   _ <- addOracle \ModulesQ -> do
     let
+      isAgda x = any (?== x) ["src//*.agda", "src//*.lagda.md"]
+
       toOut x | takeExtensions x == ".lagda.md"
               = (moduleName (dropExtensions x), WithText)
       toOut x = (moduleName (dropExtensions x), CodeOnly)
 
-    ModulesA . Map.fromList . map toOut <$> getDirectoryFiles "src" ["**/*.agda", "**/*.lagda.md"]
+    ModulesA . Map.fromList . map (toOut . dropDirectory1) . filter isAgda <$> gitFiles
   pure ()
 
 -- | Get all 1Lab modules.