[commit: ghc] master: GHCi info: Use src file for cache invalidation (969e747)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/969e747f67f57f7dd57c2e549d6a007505671158/ghc

>---------------------------------------------------------------

commit 969e747f67f57f7dd57c2e549d6a007505671158
Author: alexbiehl <alex.biehl at gmail.com>
Date:   Fri Mar 2 16:11:45 2018 -0500

    GHCi info: Use src file for cache invalidation
    
    Prior to this patch GHCi used the modification time of a module's object
    file to invalidate the info cache.
    
    We now look at the modification time of the source file, if present.
    
    This addresses part of
    https://ghc.haskell.org/trac/ghc/ticket/12706#comment:3.
    
    Reviewers: bgamari
    
    Reviewed By: bgamari
    
    Subscribers: lelf, alpmestan, rwbarton, thomie, carter
    
    GHC Trac Issues: #12706
    
    Differential Revision: https://phabricator.haskell.org/D4459


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969e747f67f57f7dd57c2e549d6a007505671158
 ghc/GHCi/UI/Info.hs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/ghc/GHCi/UI/Info.hs b/ghc/GHCi/UI/Info.hs
index fd8749a..ad390dd 100644
--- a/ghc/GHCi/UI/Info.hs
+++ b/ghc/GHCi/UI/Info.hs
@@ -276,7 +276,9 @@ collectInfo ms loaded = do
     cacheInvalid name = case M.lookup name ms of
         Nothing -> return True
         Just mi -> do
-            let fp = ml_obj_file (ms_location (modinfoSummary mi))
+            let src_fp = ml_hs_file (ms_location (modinfoSummary mi))
+                obj_fp = ml_obj_file (ms_location (modinfoSummary mi))
+                fp     = fromMaybe obj_fp src_fp
                 last' = modinfoLastUpdate mi
             exists <- doesFileExist fp
             if exists