add fluid tests

* test-suite/Makefile.am:
* test-suite/tests/fluids.test: Add some fluid tests. One is an XFAIL
  right now.

test-suite/Makefile.am

@@ -38,6 +38,7 @@ SCM_TESTS = tests/alist.test			\
 	    tests/eval.test			\
 	    tests/exceptions.test		\
 	    tests/filesys.test			\
+	    tests/fluids.test			\
 	    tests/format.test			\
 	    tests/fractions.test		\
 	    tests/ftw.test			\

test-suite/tests/fluids.test

@@ -0,0 +1,57 @@
+;;;;                                                          -*- scheme -*-
+;;;; fluids.test --- test suite for fluid values
+;;;;
+;;;; Copyright (C) 2010 Free Software Foundation, Inc.
+;;;; 
+;;;; This library is free software; you can redistribute it and/or
+;;;; modify it under the terms of the GNU Lesser General Public
+;;;; License as published by the Free Software Foundation; either
+;;;; version 3 of the License, or (at your option) any later version.
+;;;; 
+;;;; This library 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
+;;;; Lesser General Public License for more details.
+;;;; 
+;;;; You should have received a copy of the GNU Lesser General Public
+;;;; License along with this library; if not, write to the Free Software
+;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+(define-module (test-suite test-fluids)
+  :use-module (test-suite lib))
+
+
+(define a (make-fluid))
+(define b (make-fluid))
+(define c #f)
+
+(with-test-prefix "initial fluid values"
+  (pass-if "fluid-ref uninitialized fluid is #f"
+    (not (fluid-ref a))))
+
+(with-test-prefix "with-fluids with non-fluid"
+  (pass-if-exception "exception raised if nonfluid passed to with-fluids"
+                     exception:wrong-type-arg
+    (with-fluids ((c #t))
+      c))
+  
+  (expect-fail "fluids not modified if nonfluid passed to with-fluids"
+    (catch 'wrong-type-arg
+      (lambda ()
+        (with-fluids ((a #t)
+                      (c #t))
+          #f))
+      (lambda _
+        (not (fluid-ref a))))))
+
+(with-test-prefix "with-fluids with duplicate fluid"
+  (pass-if "last value wins"
+    (with-fluids ((a 1)
+                  (a 2))
+      (eqv? (fluid-ref a) 2)))
+  
+  (pass-if "original value restored"
+    (and (with-fluids ((a 1)
+                       (a 2))
+           (eqv? (fluid-ref a) 2))
+         (eqv? (fluid-ref a) #f))))