08/08: bournish: Allow compilation of multiple expressions.

[Ludovic Courtès]

civodul pushed a commit to branch master
in repository guix.

commit f82c58539e1f7b9b864e68ea2ab0c6a17c15fbb5
Author: Ludovic Courtès <address@hidden>
Date:   Mon Jun 6 18:12:31 2016 +0200

    bournish: Allow compilation of multiple expressions.
    
    * guix/build/bournish.scm (%bournish-language): Add a joiner to SCHEME.
    Compile only to Scheme.
    * tests/bournish.scm: New file.
    * Makefile.am (SCM_TESTS): Add it.
---
 Makefile.am             |    1 +
 guix/build/bournish.scm |   17 +++++++++++++++--
 tests/bournish.scm      |   42 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 58 insertions(+), 2 deletions(-)

diff --git a/Makefile.am b/Makefile.am
index 8ab574b..50cde52 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -248,6 +248,7 @@ SCM_TESTS =                                 \
   tests/profiles.scm                           \
   tests/syscalls.scm                           \
   tests/gremlin.scm                            \
+  tests/bournish.scm                           \
   tests/lint.scm                               \
   tests/publish.scm                            \
   tests/scripts.scm                            \
diff --git a/guix/build/bournish.scm b/guix/build/bournish.scm
index 3bea1c8..1f17e0a 100644
--- a/guix/build/bournish.scm
+++ b/guix/build/bournish.scm
@@ -149,11 +149,24 @@ code as an sexp."
 
 (define %bournish-language
   (let ((scheme (lookup-language 'scheme)))
+    ;; XXX: The 'scheme' language lacks a "joiner", so we add one here.  This
+    ;; allows us to have 'read-bournish' read one shell statement at a time
+    ;; instead of having to read until EOF.
+    (set! (language-joiner scheme)
+      (lambda (exps env)
+        (match exps
+          (()   '(begin))
+          ((exp) exp)
+          (_    `(begin ,@exps)))))
+
     (make-language #:name 'bournish
                    #:title "Bournish"
+
+                   ;; The reader does all the heavy lifting.
                    #:reader read-bournish
-                   #:compilers (language-compilers scheme)
-                   #:decompilers (language-decompilers scheme)
+                   #:compilers `((scheme . ,(lambda (exp env options)
+                                              (values exp env env))))
+                   #:decompilers '()
                    #:evaluator (language-evaluator scheme)
                    #:printer (language-printer scheme)
                    #:make-default-environment
diff --git a/tests/bournish.scm b/tests/bournish.scm
new file mode 100644
index 0000000..0f529ce
--- /dev/null
+++ b/tests/bournish.scm
@@ -0,0 +1,42 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2016 Ludovic Courtès <address@hidden>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (test-bournish)
+  #:use-module (guix build bournish)
+  #:use-module (system base compile)
+  #:use-module (system base language)
+  #:use-module (srfi srfi-64))
+
+
+(test-begin "bournish")
+
+(test-equal "single statement"
+  '(chdir "/foo")
+  (read-and-compile (open-input-string "cd /foo")
+                    #:from %bournish-language #:to 'scheme))
+
+(test-equal "multiple statements"
+  '(begin
+     (chdir "/foo")
+     (getcwd)
+     ((@@ (guix build bournish) ls-command-implementation)))
+  (read-and-compile (open-input-string "cd /foo\npwd\nls")
+                    #:from %bournish-language #:to 'scheme))
+
+(test-end "bournish")
+