From 7e3147666b0bb2366cfaf0ce34a11147f7f55e8f Mon Sep 17 00:00:00 2001
From: Andy Wingo <wingo@pobox.com>
Date: Thu, 10 Jun 2010 19:59:17 +0200
Subject: [PATCH] resolve-module #:ensure argument

* module/ice-9/boot-9.scm (resolve-module): Add #:ensure kwarg,
  defaulting to true. If true we make an empty module if none was found
  (the old behavior). Otherwise we return false.

* test-suite/tests/modules.test ("resolve-module"): Add tests for old
  and new behavior.
---
 module/ice-9/boot-9.scm       | 11 ++++++-----
 test-suite/tests/modules.test | 17 +++++++++++++++++
 2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/module/ice-9/boot-9.scm b/module/ice-9/boot-9.scm
index c88cbdde7..85b44b14f 100644
--- a/module/ice-9/boot-9.scm
+++ b/module/ice-9/boot-9.scm
@@ -2420,7 +2420,7 @@ If there is no handler at all, Guile prints an error and then exits."
     ;; Define the-root-module as '(guile).
     (module-define-submodule! root 'guile the-root-module)
 
-    (lambda* (name #:optional (autoload #t) (version #f))
+    (lambda* (name #:optional (autoload #t) (version #f) #:key (ensure #t))
       (let ((already (nested-ref-module root name)))
         (cond
          ((and already
@@ -2433,12 +2433,13 @@ If there is no handler at all, Guile prints an error and then exits."
          (autoload
           ;; Try to autoload the module, and recurse.
           (try-load-module name version)
-          (resolve-module name #f))
+          (resolve-module name #f #:ensure ensure))
          (else
           ;; No module found (or if one was, it had no public interface), and
-          ;; we're not autoloading. Here's the weird semantics: we ensure
-          ;; there's an empty module.
-          (or already (make-modules-in root name))))))))
+          ;; we're not autoloading. Make an empty module if #:ensure is true.
+          (or already
+              (and ensure
+                   (make-modules-in root name)))))))))
 
 
 (define (try-load-module name version)
diff --git a/test-suite/tests/modules.test b/test-suite/tests/modules.test
index a6a955f3c..5b3f7a45d 100644
--- a/test-suite/tests/modules.test
+++ b/test-suite/tests/modules.test
@@ -136,6 +136,23 @@
     (module-reverse-lookup (current-module) 'foo)))
 
 
+
+;;;
+;;; Resolve-module.
+;;;
+
+(with-test-prefix "resolve-module"
+
+  (pass-if "#:ensure #t by default"
+    (module? (resolve-module (list (gensym)))))
+
+  (pass-if "#:ensure #t explicitly"
+    (module? (resolve-module (list (gensym)) #:ensure #t)))
+
+  (pass-if "#:ensure #f"
+    (not (resolve-module (list (gensym)) #:ensure #f))))
+
+
 
 ;;;
 ;;; Observers.