From e93beb34b046b70bd14163acae0cf0922f7e4d9d Mon Sep 17 00:00:00 2001
From: Lucas Hosseini <lucas@skiplabs.io>
Date: Tue, 8 Oct 2024 14:05:25 +0200
Subject: [PATCH] [skc] Merge `fileTimeDir` into `allFilesDir`.

---
 skiplang/compiler/src/compile.sk   |  1 -
 skiplang/compiler/src/skipParse.sk | 56 +++++++++---------------------
 2 files changed, 17 insertions(+), 40 deletions(-)

diff --git a/skiplang/compiler/src/compile.sk b/skiplang/compiler/src/compile.sk
index f790a5400..223b41560 100644
--- a/skiplang/compiler/src/compile.sk
+++ b/skiplang/compiler/src/compile.sk
@@ -204,7 +204,6 @@ fun getOrInitializeBackend(
   };
 
   _ = context.mkdir(x ~> x, x ~> x, FileCache.fileDirName);
-  _ = context.mkdir(x ~> x, x ~> x, FileCache.fileTimeDirName);
   _ = context.mkdir(x ~> x, x ~> x, FileCache.allFilesDirName);
   backendDir = context.mkdir(
     SKStore.IID::keyType,
diff --git a/skiplang/compiler/src/skipParse.sk b/skiplang/compiler/src/skipParse.sk
index 05e37b4f7..7afa12ffb 100644
--- a/skiplang/compiler/src/skipParse.sk
+++ b/skiplang/compiler/src/skipParse.sk
@@ -22,7 +22,10 @@ const fileDir: SKStore.EHandle<
   fileDirName,
 );
 
-class InputPackage(name: ?String, srcs: Array<String>) extends SKStore.File
+class InputPackage(
+  name: ?String,
+  srcs: Array<(String, Int)>,
+) extends SKStore.File
 
 // Contains the paths of all source files the analysis of which has
 // been kept so far.
@@ -35,22 +38,10 @@ const allFilesDir: SKStore.EHandle<SKStore.IID, InputPackage> = SKStore.EHandle(
   allFilesDirName,
 );
 
-const fileTimeDirName: SKStore.DirName = SKStore.DirName::create(
-  "/fileTimeCache/",
-);
-const fileTimeDir: SKStore.EHandle<
-  SKStore.SID,
-  SKStore.IntFile,
-> = SKStore.EHandle(
-  SKStore.SID::keyType,
-  SKStore.IntFile::type,
-  fileTimeDirName,
-);
-
 fun pkgDelta(
   old_srcs: Array<(String, Int)>,
   new_srcs: Array<(String, Int)>,
-): (Array<(String, Int)>, Array<(String, Int)>, Array<(String, Int)>) {
+): (Array<String>, Array<String>, Array<String>) {
   added_files = mutable Vector[];
   modified_files = mutable Vector[];
   deleted_files = mutable Vector[];
@@ -60,16 +51,16 @@ fun pkgDelta(
     old_srcs.find(s -> s.i0 == src) match {
     | Some((_, old_mtime)) ->
       if (mtime != old_mtime) {
-        modified_files.push((src, mtime))
+        modified_files.push(src)
       }
-    | None() -> added_files.push((src, mtime))
+    | None() -> added_files.push(src)
     }
   };
 
   // FIXME: This is O(n^2).
-  for ((src, mtime) in old_srcs) {
+  for ((src, _) in old_srcs) {
     if (!new_srcs.any(s -> s.i0 == src)) {
-      deleted_files.push((src, mtime))
+      deleted_files.push(src)
     }
   };
 
@@ -110,14 +101,7 @@ fun writeFiles(
   // Files kept in the previous run.
   old_files = mutable Map[];
   for (pkg in allFilesDir.unsafeGetArray(context, SKStore.IID(0))) {
-    srcs_with_mtime = pkg.srcs
-      .map(fn -> {
-        key = formatPkgSrc(pkg.name, fn);
-        mtime = fileTimeDir.unsafeGetArray(context, SKStore.SID(key))[0].value;
-        (fn, mtime)
-      })
-      .collect(Array);
-    old_files.set(pkg.name, srcs_with_mtime)
+    old_files.set(pkg.name, pkg.srcs)
   };
 
   stale_pkgs = mutable Vector<?String>[];
@@ -132,7 +116,7 @@ fun writeFiles(
     ) {
       pkgDelta(old_files[pkg_opt], srcs.map(src -> (src.i0, src.i1)));
     } else {
-      (srcs.map(src -> (src.i0, src.i1)), Array[], Array[])
+      (srcs.map(src -> src.i0), Array[], Array[])
     };
 
     if (
@@ -145,15 +129,10 @@ fun writeFiles(
     stale_pkgs.push(pkg_opt);
 
     // Update added/modified files.
-    for ((src_path, src_mtime) in added_files.concat(modified_files)) {
+    for (src_path in added_files.concat(modified_files)) {
       key = formatPkgSrc(pkg_opt, src_path);
       // FIXME: This is O(n).
       src_contents = srcs.find(src ~> src.i0 == src_path).fromSome().i2;
-      fileTimeDir.writeArray(
-        context,
-        SKStore.SID(key),
-        Array[SKStore.IntFile(src_mtime)],
-      );
       fileDir.writeArray(
         context,
         SKStore.SID(key),
@@ -161,27 +140,26 @@ fun writeFiles(
       )
     };
     // Invalidate deleted files.
-    for ((src_path, _) in deleted_files) {
+    for (src_path in deleted_files) {
       key = formatPkgSrc(pkg_opt, src_path);
       fileDir.writeArray(
         context,
         SKStore.SID(key),
         Array[SKStore.StringFile("")],
-      );
-      fileTimeDir.writeArray(context, SKStore.SID(key), Array[])
+      )
     }
   };
 
-  // Keep analysis for all non-stale packages.
   new_old_files = current_files
-    .map((_, srcs) -> srcs.map(src -> src.i0))
+    .map((_, srcs) -> srcs.map(src -> (src.i0, src.i1)))
     .clone();
+  // Keep analysis for all non-stale packages.
   for (pkg_opt => srcs in old_files) {
     // FIXME: This is O(n).
     if (stale_pkgs.contains(pkg_opt)) {
       continue
     };
-    new_old_files.set(pkg_opt, srcs.map(src -> src.i0).collect(Array))
+    new_old_files.set(pkg_opt, srcs)
   };
 
   allFilesDir.writeArray(