Work with fsevents/cf libs

.github/workflows/test.yml

@@ -0,0 +1,34 @@
+name: Main workflow
+
+on:
+  - pull_request
+  - push
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - macos-latest
+        ocaml-version:
+          - 4.12.0
+          - 4.11.1
+          - 4.10.2
+          - 4.09.1
+          - 4.08.1
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Use OCaml ${{ matrix.ocaml-version }}
+        uses: avsm/setup-ocaml@v1
+        with:
+          ocaml-version: ${{ matrix.ocaml-version }}
+      - run: opam pin add . --no-action
+      - run: opam depext irmin-watcher --yes --with-doc --with-test
+      - run: opam install . --deps-only --with-doc --with-test
+      - run: opam exec -- dune build
+      - run: opam exec -- dune runtest

.ocamlformat

@@ -1,4 +1,4 @@
-version = 0.14.2
+version = 0.18.0
 break-infix = fit-or-vertical
 parse-docstrings = true
 indicate-multiline-delimiters = no

CHANGES.md

@@ -1,3 +1,11 @@
+### dev
+
+- Switch to GitHub Actions from Travis (#31, @avsm)
+- Initialise backends only when needed via a
+  lazy watcher interface (#31, @samoht @avsm)
+- Use fsevents and cf-lwt packages (#31, @avsm)
+- Use ocamlformat.0.18.0 (#31, @avsm)
+
 ### 0.4.1 (2019-07-02)
 
 - Clearer name for hook logger (@talex5, #21)

irmin-watcher.opam

@@ -8,7 +8,7 @@ bug-reports:  "https://github.com/mirage/irmin-watcher/issues"
 license:      "ISC"
 
 build: [
-  ["dune" "subst"] {pinned}
+  ["dune" "subst"] {dev}
   ["dune" "build" "-p" name "-j" jobs]
 ]
 
@@ -23,16 +23,24 @@ depends: [
   "logs"
   "fmt"
   "astring"
-  "inotify"      {os = "linux"}
-  "osx-fsevents" {os = "macos" & >= "0.2.0"}
+  "inotify"  {os = "linux"}
+  "cf-lwt"
+  "fsevents-lwt"
 ]
 
 synopsis: "Portable Irmin watch backends using FSevents or Inotify"
 description: """
 irmin-watcher implements [Irmin's watch hooks][watch] for various OS,
-using FSevents in OSX and Inotify on Linux.
+using FSevents in macOS and Inotify on Linux.
 
 irmin-watcher is distributed under the ISC license.
 
 [watch]: http://mirage.github.io/irmin/irmin/Irmin/Private/Watch/index.html#type-hook
 """
+
+pin-depends: [
+  [ "fsevents.dev" "git+https://github.com/mirage/ocaml-fsevents.git#f9e797e16bdbc730804cd684f07808022495c333" ]
+  [ "fsevents-lwt.dev" "git+https://github.com/mirage/ocaml-fsevents.git#f9e797e16bdbc730804cd684f07808022495c333" ]
+  [ "cf.dev" "git+https://github.com/mirage/ocaml-cf.git#918e2b9a7ab6871e48cce0508bce5e45981375f6" ]
+  [ "cf-lwt.dev" "git+https://github.com/mirage/ocaml-cf.git#918e2b9a7ab6871e48cce0508bce5e45981375f6" ]
+]

src/backend.fsevents.ml

@@ -73,7 +73,7 @@ let v =
     stop_runloop () >>= fun () ->
     unlisten () >>= fun () -> unpoll ()
   in
-  Core.create listen
+  lazy (Core.create listen)
 
 let mode = `FSEvents
 

src/backend.fsevents.mli

@@ -8,7 +8,7 @@
 
     {e %%VERSION%% — {{:%%PKG_HOMEPAGE%%} homepage}} *)
 
-val v : Core.t
+val v : Core.t Lazy.t
 (** [v id p f] is the hook calling [f] everytime a sub-path of [p] is modified.
     Return a function to call to remove the hook. Use the FSevent framework to
     be notified on filesystem changes. *)

src/backend.inotify.ml

@@ -78,7 +78,7 @@ let v =
     stop_watch () >>= fun () ->
     unlisten () >>= fun () -> unpoll ()
   in
-  Core.create listen
+  lazy (Core.create listen)
 
 let mode = `Inotify
 

src/backend.inotify.mli

@@ -8,7 +8,7 @@
 
     {e %%VERSION%% — {{:%%PKG_HOMEPAGE%%} homepage}} *)
 
-val v : Core.t
+val v : Core.t Lazy.t
 (** [v id p f] is the hook calling [f] everytime a sub-path of [p] is modified.
     Return a function to call to remove the hook. Use inofity to be notified on
     filesystem changes. *)

src/dune

@@ -12,12 +12,12 @@
   (select
    backend.ml
    from
-   (osx-cf.lwt osx-fsevents.lwt -> backend.fsevents.ml)
+   (cf-lwt fsevents-lwt -> backend.fsevents.ml)
    (inotify.lwt -> backend.inotify.ml)
    (lwt.unix -> backend.polling.ml))
   (select
    backend.mli
    from
-   (osx-cf.lwt osx-fsevents.lwt -> backend.fsevents.mli)
+   (cf-lwt fsevents-lwt -> backend.fsevents.mli)
    (inotify.lwt -> backend.inotify.mli)
    (lwt.unix -> backend.polling.mli))))

src/irmin_watcher.ml

@@ -4,7 +4,7 @@
    %%NAME%% %%VERSION%%
   ---------------------------------------------------------------------------*)
 
-let v = Backend.v
+let v = Lazy.force Backend.v
 
 let mode = (Backend.mode :> [ `FSEvents | `Inotify | `Polling ])
 

src/polling.ml

@@ -10,19 +10,21 @@ let src = Logs.Src.create "irw-polling" ~doc:"Irmin watcher using using polling"
 
 module Log = (val Logs.src_log src : Logs.LOG)
 
-let with_delay delay =
+let listen ~wait_for_changes dir =
   Log.info (fun l -> l "Polling mode");
+  Hook.v ~wait_for_changes ~dir
+
+let with_delay delay =
   let wait_for_changes () = Lwt_unix.sleep delay >|= fun () -> `Unknown in
-  Core.create (fun dir -> Hook.v ~wait_for_changes ~dir)
+  Core.create (listen ~wait_for_changes)
 
 let mode = `Polling
 
 let v =
-  Log.info (fun l -> l "Polling mode");
   let wait_for_changes () =
     Lwt_unix.sleep !Core.default_polling_time >|= fun () -> `Unknown
   in
-  Core.create (fun dir -> Hook.v ~wait_for_changes ~dir)
+  lazy (Core.create (listen ~wait_for_changes))
 
 (*---------------------------------------------------------------------------
    Copyright (c) 2016 Thomas Gazagnaire

src/polling.mli

@@ -15,7 +15,7 @@ val with_delay : float -> t
     [p] is modified. Return a function to call to remove the hook. Active
     polling is done every [delay] seconds. *)
 
-val v : t
+val v : t Lazy.t
 (** [v] is [with_delay !default_polling_time]. *)
 
 val mode : [ `Polling ]

test/dune

@@ -1,3 +1,9 @@
-(test
+(executable
  (name test)
  (libraries alcotest logs.fmt irmin-watcher mtime mtime.clock.os))
+
+(rule
+ (alias runtest)
+ (deps test.exe)
+ (action
+  (run ./test.exe -q --color=always)))

test/test.ml

@@ -31,7 +31,7 @@ let write f d =
 let move a b = Unix.rename (tmpdir / a) (tmpdir / b)
 
 let remove f =
-  try Unix.unlink (tmpdir / f) with e -> Alcotest.fail @@ Printexc.to_string e
+  try Unix.unlink (tmpdir / f) with e -> Alcotest.fail (Printexc.to_string e)
 
 let poll ~mkdir:m i () =
   if m then mkdir tmpdir;
@@ -109,7 +109,7 @@ let polling_tests =
     ("enoent", `Quick, run (poll ~mkdir:false 0));
     ("basic", `Quick, run (poll ~mkdir:true 0));
     ("100s", `Quick, run (random_polls 100));
-    ("1000s", `Quick, run (random_polls 1000));
+    ("1000s", `Slow, run (random_polls 1000));
   ]
 
 let mode =