derivations: Raise an error when a module file is not found.

Suggested by Jookia.

* guix/derivations.scm (&file-search-error): New error condition.
(search-path*): Raise it when 'search-path' returns #f.
* guix/gexp.scm (search-path*): Remove.
* guix/ui.scm (call-with-error-handling): Add case for
'file-search-error?'.
* tests/derivations.scm ("build-expression->derivation and invalid
module name"): New test.

1 files changed, 9 insertions, 0 deletions

diff --git a/tests/derivations.scm b/tests/derivations.scm
index 4d3b82fe1a6..a52142e0f1d 100644
--- a/tests/derivations.scm
+++ b/tests/derivations.scm
@@ -570,6 +570,15 @@
 
 (test-skip (if (%guile-for-build) 0 8))
 
+(test-equal "build-expression->derivation and invalid module name"
+  '(file-search-error "guix/module/that/does/not/exist.scm")
+  (guard (c ((file-search-error? c)
+             (list 'file-search-error
+                   (file-search-error-file-name c))))
+    (build-expression->derivation %store "foo" #t
+                                  #:modules '((guix module that
+                                                    does not exist)))))
+
 (test-assert "build-expression->derivation and derivation-prerequisites"
   (let ((drv (build-expression->derivation %store "fail" #f)))
     (any (match-lambda