Merge pull request #2043 from OCamlPro/fix-update

Fix update bug introduced in fef5f07

doc/pages/FAQ.md

@@ -301,3 +301,15 @@ If for some reason you want the old behaviour, use one of:
 * an address of the form `vc-controlled-dir#branch`, typically `#master`
 * on Git you can use `#HEAD` to always get to the currently checked out branch
   (which used to be the default, and still is for remote gits)
+
+---
+
+#### 🐫  OPAM wants to do reinstallations after update. Can I skip them ?
+
+OPAM registers the need to recompile packages when they had meaningful changes
+in the repository, to guarantee consistency and allow to propagate fixes to
+already installed packages ; the official repository maintainers generally don't
+abuse this. There is no built-in command to reset them, in purpose, but removing
+the file `~/.opam/<switch>/reinstall` is enough to make OPAM forget about them.
+It's quite safe, but don't report issues if you did and your system is not up to
+date, obviously.

src/client/opamState.ml

@@ -183,7 +183,7 @@ let package_state_one t all nv =
     | `all ->
       OpamFilename.checksum opam
       @ OpamFilename.checksum descr
-      @ OpamRepository.url_checksum url
+      @ OpamFilename.checksum url
       @ OpamFilename.checksum_dir files
       @ OpamFilename.checksum archive
     | `partial true ->

src/core/opamRepository.ml

@@ -267,7 +267,12 @@ let package_state repo prefix nv all =
   let fs = match all with
     | `all       -> package_files repo prefix nv ~archive:true
     | `partial b -> package_important_files repo prefix nv ~archive:b in
-  let l = List.map OpamFilename.checksum fs in
+  let url = OpamPath.Repository.url repo prefix nv in
+  let l =
+    List.map (fun f ->
+        if all <> `all && f = url then url_checksum f
+        else OpamFilename.checksum f)
+      fs in
   List.flatten l
 
 (* Sort repositories by priority *)

src/core/opamRepository.mli

@@ -62,15 +62,19 @@ val compiler_index: repository repository_name_map -> (repository_name * string
 
 (** {2 State} *)
 
-(** Get the meaningful checksum off an url file *)
+(** Get the package archive checksum off an url file *)
 val url_checksum: OpamFilename.t -> checksums
 
 (** Get all the package files *)
 val package_files: repository -> string option -> package -> archive:bool ->
   filename list
 
-(** Compute a package state (ie. a list of checksums). *)
-val package_state: repository -> string option -> package -> [`all|`partial of bool]
+(** Compute a package state (ie. a list of checksums). If [`partial archive],
+    only the checksum of the archive within the url file (instead of the file
+    itself), of the files/ subdirectory, and of the archive if set are
+    returned. *)
+val package_state: repository -> string option -> package ->
+  [`all|`partial of bool]
   -> checksums
 
 (** Get all the compiler files *)