env: add '--bindings' flag to output as environment variable bindings

Author: rjbou

master_changes.md

@@ -69,6 +69,7 @@ users)
 ## Clean
 
 ## Env
+  * [NEW] Add `--bindings` option to output env as environment variable binding, useful for CI environment populating [#6316 @rjbou - fix #5791]
 
 ## Opamfile
 

src/client/opamCommands.ml

@@ -1302,9 +1302,15 @@ let option cli =
           $global_options cli $fieldvalue $global cli)
 
 module Common_config_flags = struct
-  let sexp cli =
-    mk_flag ~cli cli_original ["sexp"]
-      "Print environment as an s-expression rather than in shell format"
+  let env_format cli =
+    mk_vflag ~cli None [
+      cli_original, Some `sexp, ["sexp"],
+      "Print environment as an s-expression rather than in shell format";
+      cli_from cli2_4, Some `bindingss, ["bindingss"],
+      "Print environment as variable bindings rather than in shell format.\
+       Useful to populate CI environment."
+    ]
+
 
   let inplace_path cli =
     mk_flag ~cli cli_original ["inplace-path"]
@@ -1402,7 +1408,7 @@ let config cli =
   let open Common_config_flags in
 
   let config global_options
-      command shell sexp inplace_path
+      command shell env_format inplace_path
       set_opamroot set_opamswitch params () =
     apply_global_options cli global_options;
     let shell = match shell with
@@ -1418,7 +1424,7 @@ let config cli =
        | Some sw ->
          `Ok (OpamConfigCommand.env gt sw
                 ~set_opamroot ~set_opamswitch
-                ~csh:(shell=SH_csh) ~sexp ~fish:(shell=SH_fish)
+                ~csh:(shell=SH_csh) ~env_format ~fish:(shell=SH_fish)
                 ~pwsh ~cmd:(shell=SH_cmd)
                 ~inplace_path))
     | Some `revert_env, [] ->
@@ -1428,7 +1434,7 @@ let config cli =
        | Some sw ->
          `Ok (OpamConfigCommand.ensure_env gt sw;
               OpamConfigCommand.print_eval_env
-                ~csh:(shell=SH_csh) ~sexp ~fish:(shell=SH_fish)
+                ~csh:(shell=SH_csh) ~env_format ~fish:(shell=SH_fish)
                 ~pwsh ~cmd:(shell=SH_cmd)
                 (OpamEnv.add [] [])))
     | Some `list, [] ->
@@ -1640,7 +1646,8 @@ let config cli =
 
   mk_command_ret  ~cli cli_original "config" ~doc ~man
     Term.(const config
-          $global_options cli $command $shell_opt cli cli_original $sexp cli
+          $global_options cli $command $shell_opt cli cli_original
+          $env_format cli
           $inplace_path cli
           $set_opamroot cli $set_opamswitch cli
           $params)
@@ -1711,7 +1718,7 @@ let env cli =
        after printing the list of not up-to-date variables."
   in
   let env
-      global_options shell sexp inplace_path set_opamroot set_opamswitch
+      global_options shell env_format inplace_path set_opamroot set_opamswitch
       revert check () =
     apply_global_options cli global_options;
     if check then
@@ -1733,19 +1740,19 @@ let env cli =
        | Some sw ->
          OpamConfigCommand.env gt sw
            ~set_opamroot ~set_opamswitch
-           ~csh:(shell=SH_csh) ~sexp ~fish:(shell=SH_fish)
+           ~csh:(shell=SH_csh) ~env_format ~fish:(shell=SH_fish)
            ~pwsh ~cmd:(shell=SH_cmd)
            ~inplace_path);
     | true ->
       OpamConfigCommand.print_eval_env
-        ~csh:(shell=SH_csh) ~sexp ~fish:(shell=SH_fish)
+        ~csh:(shell=SH_csh) ~env_format ~fish:(shell=SH_fish)
         ~pwsh ~cmd:(shell=SH_cmd)
         (OpamEnv.add [] [])
   in
   let open Common_config_flags in
   mk_command  ~cli cli_original "env" ~doc ~man
   Term.(const env
-        $global_options cli $shell_opt cli cli_original $sexp cli
+        $global_options cli $shell_opt cli cli_original $env_format cli
         $inplace_path cli $set_opamroot cli $set_opamswitch cli
         $revert $check)
 

src/client/opamConfigCommand.ml

@@ -131,6 +131,16 @@ let print_sexp_env output env =
   aux env;
   output ")\n"
 
+let print_bindingss_env output env =
+  let rec aux = function
+    | [] -> ()
+    | (k, v, _) :: r ->
+      if not (List.exists (fun (k1, _, _) -> k = k1) r) then
+        Printf.ksprintf output "%s=%s\n" k v;
+      aux r
+  in
+  aux env
+
 let rec print_fish_env output env =
   let set_arr_cmd ?(modf=fun x -> x) k v =
     let v = modf @@ OpamStd.String.split v ':' in
@@ -183,7 +193,7 @@ let print_without_cr s =
     output_string stdout s;
     flush stdout
 
-let print_eval_env ~csh ~sexp ~fish ~pwsh ~cmd env =
+let print_eval_env ~csh ~env_format ~fish ~pwsh ~cmd env =
   let env = (env : OpamTypes.env :> (string * string * string option) list) in
   let output_normally = OpamConsole.msg "%s" in
   let never_with_cr =
@@ -192,18 +202,22 @@ let print_eval_env ~csh ~sexp ~fish ~pwsh ~cmd env =
     else
       output_normally
   in
-  if sexp then
+  match env_format with
+  | Some `sexp ->
     print_sexp_env output_normally env
-  else if csh then
-    print_csh_env never_with_cr env
-  else if fish then
-    print_fish_env never_with_cr env
-  else if pwsh then
-    print_pwsh_env output_normally env
-  else if cmd then
-    print_cmd_env output_normally env
-  else
-    print_env never_with_cr env
+  | Some `bindingss ->
+    print_bindingss_env output_normally env
+  | None ->
+    if csh then
+      print_csh_env never_with_cr env
+    else if fish then
+      print_fish_env never_with_cr env
+    else if pwsh then
+      print_pwsh_env output_normally env
+    else if cmd then
+      print_cmd_env output_normally env
+    else
+      print_env never_with_cr env
 
 let check_writeable l =
   let map_writeable ({OpamTypes.envu_op; _} as update) =
@@ -331,7 +345,7 @@ let ensure_env gt switch =
   ignore (ensure_env_aux gt switch)
 
 let env gt switch ?(set_opamroot=false) ?(set_opamswitch=false)
-    ~csh ~sexp ~fish ~pwsh ~cmd ~inplace_path =
+    ~csh ~env_format ~fish ~pwsh ~cmd ~inplace_path =
   log "config-env";
   let opamroot_not_current =
     let current = gt.root in
@@ -371,7 +385,7 @@ let env gt switch ?(set_opamroot=false) ?(set_opamswitch=false)
   let env =
     ensure_env_aux ~set_opamroot ~set_opamswitch ~force_path gt switch
   in
-  print_eval_env ~csh ~sexp ~fish ~pwsh ~cmd env
+  print_eval_env ~csh ~env_format ~fish ~pwsh ~cmd env
 [@@ocaml.warning "-16"]
 
 let subst gt fs =

src/client/opamConfigCommand.mli

@@ -16,23 +16,28 @@ open OpamStateTypes
 
 (** {2 `opam config` subcommand and their associated commands } *)
 
-(** Display the current environment. Booleans csh, sexp and fish set an
-    alternative output (unspecified if more than one is true, sh-style by
-    default). [inplace_path] changes how the PATH variable is updated when there
-    is already an opam entry: either at the same rank, or pushed in front. *)
+(** Display the current environment. Booleans [csh], [env_format] and [fish]
+    set an alternative output (unspecified if more than one is true, sh-style
+    by default). [inplace_path] changes how the PATH variable is updated when
+    there is already an opam entry: either at the same rank, or pushed in
+    front. *)
 val env:
   'a global_state -> switch ->
   ?set_opamroot:bool -> ?set_opamswitch:bool ->
-  csh:bool -> sexp:bool -> fish:bool -> pwsh:bool -> cmd:bool ->
-  inplace_path:bool -> unit
+  csh:bool -> env_format:[< `sexp | `bindingss ] option -> fish:bool ->
+  pwsh:bool -> cmd:bool -> inplace_path:bool ->
+  unit
 
 (** Ensures that the environment file exists in the given switch, regenerating
     it, if necessary. *)
 val ensure_env: 'a global_state -> switch -> unit
 
 (** Like [env] but allows one to specify the precise env to print rather than
     compute it from a switch state *)
-val print_eval_env: csh:bool -> sexp:bool -> fish:bool -> pwsh:bool -> cmd:bool -> env -> unit
+val print_eval_env:
+  csh:bool -> env_format:[< `sexp | `bindingss ] option -> fish:bool -> pwsh:bool ->
+  cmd:bool -> env
+  -> unit
 
 (** Display the content of all available packages variables *)
 val list: 'a switch_state -> name list -> unit

tests/reftests/env.test

@@ -651,3 +651,29 @@ OPAM_PACKAGE_NAME=another-package
 OPAM_PACKAGE_VERSION=another-version
 OPAM_SWITCH_PREFIX=${BASEDIR}/OPAM/bd
 PATH=${BASEDIR}/OPAM/bd/bin:another-path
+### : opam env outputs :
+### opam switch create outputs --empty
+### <pkg:op.1>
+opam-version: "2.0"
+setenv: [ PKGVAR = "piou"]
+### opam install op -y
+The following actions will be performed:
+=== install 1 package
+  - install op 1
+
+<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
+-> installed op.1
+Done.
+### opam exec -- opam env --sexp | grep -v "OPAM_LAST_ENV|MANPATH|PATH"
+(
+  ("OPAM_SWITCH_PREFIX" "${BASEDIR}/OPAM/outputs")
+  ("PKGVAR" "piou")
+)
+### opam exec -- opam env --bindingss | grep -v "OPAM_LAST_ENV|MANPATH|PATH"
+OPAM_SWITCH_PREFIX=${BASEDIR}/OPAM/outputs
+PKGVAR=piou
+### opam exec -- opam env --bindingss --sexp
+opam: options '--sexp' and '--bindingss' cannot be present at the same time
+Usage: opam env [OPTION]…
+Try 'opam env --help' or 'opam --help' for more information.
+# Return code 2 #