01/05: grafts: Actually cache grafts during the derivation DAG traversal.

[Ludovic Courtès]

civodul pushed a commit to branch master
in repository guix.

commit 90ad5c8836138b7fd4d1bd0243dfa8b30ae0cf21
Author: Ludovic Courtès <address@hidden>
Date:   Mon Jan 16 21:59:00 2017 +0100

    grafts: Actually cache grafts during the derivation DAG traversal.
    
    This fixes a regression introduced in
    d38bc9a9f6feefc465964531520fee5663a12f48 whereby the cache was
    effectively disabled.
    
    Reported by Thomas Danckaert <address@hidden>.
    
    * guix/grafts.scm (with-cache): In the cache miss case, wrap body in
    'mbegin'.
---
 guix/grafts.scm |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/guix/grafts.scm b/guix/grafts.scm
index 2006d39..b60c8cf 100644
--- a/guix/grafts.scm
+++ b/guix/grafts.scm
@@ -222,8 +222,9 @@ available."
        (return result))
       (#f                                         ;cache miss
        (mlet %state-monad ((result (begin exp ...)))
-         (set-current-state (vhash-consq key result cache))
-         (return result))))))
+         (mbegin %state-monad
+           (set-current-state (vhash-consq key result cache))
+           (return result)))))))
 
 (define* (cumulative-grafts store drv grafts
                             references