Add a --context argument to dune install/uninstall

CHANGES.md

@@ -99,6 +99,8 @@
 - Add (dialect ...) stanza
   (@nojb, #2404)
 
+- Add a `--context` argument to `dune install/uninstall` (@diml, #2412)
+
 1.10.0 (04/06/2019)
 -------------------
 

bin/install_uninstall.ml

@@ -282,12 +282,23 @@ let install_uninstall ~what =
           )
     and+ pkgs =
       Arg.(value & pos_all package_name [] name_)
+    and+ context =
+      Arg.(value
+           & opt (some string) None
+           & info ["context"] ~docv:"CONTEXT"
+               ~doc:"Select context to install from. By default, \
+                     install files from all defined contexts.")
     in
     Common.set_common common ~targets:[];
     let log = Log.create common in
     Scheduler.go ~log ~common (fun () ->
       let open Fiber.O in
       let* workspace = Import.Main.scan_workspace ~log common in
+      let contexts =
+        match context with
+        | None -> workspace.contexts
+        | Some name -> [Import.Main.find_context_exn workspace ~name]
+      in
       let pkgs =
         match pkgs with
         | [] -> Package.Name.Map.keys workspace.conf.packages
@@ -296,7 +307,7 @@ let install_uninstall ~what =
       let install_files, missing_install_files =
         List.concat_map pkgs ~f:(fun pkg ->
           let fn = resolve_package_install workspace pkg in
-          List.map workspace.contexts ~f:(fun ctx ->
+          List.map contexts ~f:(fun ctx ->
             let fn = Path.append_source (Path.build ctx.Context.build_dir) fn in
             if Path.exists fn then
               Left (ctx, (pkg, fn))
@@ -313,7 +324,7 @@ let install_uninstall ~what =
           ~hints:[ Pp.text "try running: dune build @install" ]
       end;
       (match
-         workspace.contexts,
+         contexts,
          prefix_from_command_line,
          libdir_from_command_line
        with

test/blackbox-tests/dune.inc

@@ -889,6 +889,14 @@
    test-cases/install-libdir
    (progn (run %{exe:cram.exe} -test run.t) (diff? run.t run.t.corrected)))))
 
+(alias
+ (name install-multiple-contexts)
+ (deps (package dune) (source_tree test-cases/install-multiple-contexts))
+ (action
+  (chdir
+   test-cases/install-multiple-contexts
+   (progn (run %{exe:cram.exe} -test run.t) (diff? run.t run.t.corrected)))))
+
 (alias
  (name install-partial-package)
  (deps (package dune) (source_tree test-cases/install-partial-package))
@@ -1734,6 +1742,7 @@
   (alias inline_tests)
   (alias install-dry-run)
   (alias install-libdir)
+  (alias install-multiple-contexts)
   (alias install-partial-package)
   (alias install-rule-order)
   (alias install-with-var)
@@ -1923,6 +1932,7 @@
   (alias include-loop)
   (alias include-qualified)
   (alias inline_tests)
+  (alias install-multiple-contexts)
   (alias install-partial-package)
   (alias install-rule-order)
   (alias install-with-var)

test/blackbox-tests/test-cases/install-multiple-contexts/run.t

@@ -0,0 +1,44 @@
+Test installation when multiple contexts are defined
+
+  $ cat > dune-workspace <<EOF
+  > (lang dune 1.11)
+  > (context (default (name a)))
+  > (context (default (name b)))
+  > EOF
+
+  $ cat > dune-project <<EOF
+  > (lang dune 1.11)
+  > (package (name a))
+  > EOF
+
+  $ cat > dune <<EOF
+  > (rule (with-stdout-to hello (echo "Hello, world!")))
+  > (install (section share) (files hello))
+  > EOF
+
+  $ dune build @install
+
+Cannot install into a specific prefix with multiple contexts defined:
+
+  $ dune install --prefix _install
+  Error: Cannot specify --prefix or --libdir when installing into multiple
+  contexts!
+  [1]
+
+One must pass a --context argument:
+
+  $ dune install --prefix _install/a --context a
+  Installing _install/a/lib/a/META
+  Installing _install/a/lib/a/dune-package
+  Installing _install/a/share/a/hello
+
+  $ dune install --prefix _install/b --context b
+  Installing _install/b/lib/a/META
+  Installing _install/b/lib/a/dune-package
+  Installing _install/b/share/a/hello
+
+Passing an invalid context name fails:
+
+  $ dune install --prefix _install/c --context c
+  Error: Context "c" not found!
+  [1]