guix build: Add '--manifest' option.

* guix/scripts/build.scm (show-help): Document --manifest argument.
(options->things-to-build): When given a manifest, evaluate all the entries.
* tests/guix-build.sh: Add test for --manifest.
* doc/guix.texi (Additional Build Options): Mention --manifest.
* etc/completion/bash/guix: Complete file name if 'guix build' argument is
-m.

doc/guix.texi

@@ -46,7 +46,7 @@ Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
 Copyright @copyright{} 2017 Thomas Danckaert@*
 Copyright @copyright{} 2017 humanitiesNerd@*
 Copyright @copyright{} 2017 Christopher Allan Webber@*
-Copyright @copyright{} 2017, 2018, 2019 Marius Bakke@*
+Copyright @copyright{} 2017, 2018, 2019, 2020 Marius Bakke@*
 Copyright @copyright{} 2017, 2019, 2020 Hartmut Goebel@*
 Copyright @copyright{} 2017, 2019, 2020 Maxim Cournoyer@*
 Copyright @copyright{} 2017, 2018, 2019, 2020 Tobias Geerinckx-Rice@*
@@ -8456,6 +8456,11 @@ As an example, @var{file} might contain a package definition like this
 @include package-hello.scm
 @end lisp
 
+@item --manifest=@var{manifest}
+@itemx -m @var{manifest}
+Build all packages listed in the given @var{manifest}
+(@pxref{profile-manifest, @option{--manifest}}).
+
 @item --expression=@var{expr}
 @itemx -e @var{expr}
 Build the package or derivation @var{expr} evaluates to.

etc/completion/bash/guix

@@ -178,7 +178,7 @@ _guix_complete ()
 		_guix_complete_installed_package "$word_at_point"
             elif _guix_is_command "build"
             then
-                if _guix_is_dash_L
+                if _guix_is_dash_L || _guix_is_dash_m
                 then
                     _guix_complete_file
 		else

guix/scripts/build.scm

@@ -1,6 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2013 Mark H Weaver <mhw@netris.org>
+;;; Copyright © 2020 Marius Bakke <mbakke@fastmail.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -34,6 +35,7 @@
 
   #:use-module (guix monads)
   #:use-module (guix gexp)
+  #:use-module (guix profiles)
   #:autoload   (guix http-client) (http-fetch http-get-error?)
   #:use-module (ice-9 format)
   #:use-module (ice-9 match)
@@ -680,6 +682,9 @@ Build the given PACKAGE-OR-DERIVATION and return their output paths.\n"))
   -f, --file=FILE        build the package or derivation that the code within
                          FILE evaluates to"))
   (display (G_ "
+  -m, --manifest=FILE    build the packages that the manifest given in FILE
+                         evaluates to"))
+  (display (G_ "
   -S, --source           build the packages' source derivations"))
   (display (G_ "
       --sources[=TYPE]   build source derivations; TYPE may optionally be one
@@ -768,6 +773,9 @@ must be one of 'package', 'all', or 'transitive'~%")
          (option '(#\f "file") #t #f
                  (lambda (opt name arg result)
                    (alist-cons 'file arg result)))
+         (option '(#\m "manifest") #t #f
+                 (lambda (opt name arg result)
+                   (alist-cons 'manifest arg result)))
          (option '(#\n "dry-run") #f #f
                  (lambda (opt name arg result)
                    (alist-cons 'dry-run? #t (alist-cons 'graft? #f result))))
@@ -804,6 +812,14 @@ build---packages, gexps, derivations, and so on."
       (for-each validate-type lst)
       lst))
 
+  ;; Note: Taken from (guix scripts refresh).
+  (define (manifest->packages manifest)
+    "Return the list of packages in MANIFEST."
+    (filter-map (lambda (entry)
+                  (let ((item (manifest-entry-item entry)))
+                    (if (package? item) item #f)))
+                (manifest-entries manifest)))
+
   (append-map (match-lambda
                 (('argument . (? string? spec))
                  (cond ((derivation-path? spec)
@@ -827,6 +843,9 @@ build---packages, gexps, derivations, and so on."
                         (list (specification->package spec)))))
                 (('file . file)
                  (ensure-list (load* file (make-user-module '()))))
+                (('manifest . manifest)
+                 (manifest->packages
+                  (load* manifest (make-user-module '((guix profiles) (gnu))))))
                 (('expression . str)
                  (ensure-list (read/eval str)))
                 (('argument . (? derivation? drv))

tests/guix-build.sh

@@ -1,5 +1,6 @@
 # GNU Guix --- Functional package management for GNU
 # Copyright © 2012, 2013, 2014, 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org>
+# Copyright © 2020 Marius Bakke <mbakke@fastmail.com>
 #
 # This file is part of GNU Guix.
 #
@@ -308,6 +309,14 @@ cat > "$module_dir/gexp.scm"<<EOF
 EOF
 guix build --file="$module_dir/gexp.scm" -d
 guix build --file="$module_dir/gexp.scm" -d | grep 'gexp\.drv'
+
+# Building from a manifest file.
+cat > "$module_dir/manifest.scm"<<EOF
+(specifications->manifest '("hello" "guix"))
+EOF
+test `guix build -d --manifest="$module_dir/manifest.scm" \
+      | grep -e '-hello-' -e '-guix-' \
+      | wc -l` -eq 2
 rm "$module_dir"/*.scm
 
 # Using 'GUIX_BUILD_OPTIONS'.