The QuickCheck library swapped the order of the arguments of the 'cover'
function in version 2.12.  Version 0.3.4 of the Diff library still uses
the old argument order.  Swapping the argument order makes Diff work
with newer versions of QuickCheck.

See <https://github.com/commercialhaskell/stackage/issues/4289> for the
upstream bug report.

diff -ruN a/test/Test.hs b/test/Test.hs
--- a/test/Test.hs	2016-04-23 01:21:45.000000000 -0400
+++ b/test/Test.hs	2019-11-01 19:13:04.590770903 -0400
@@ -134,7 +134,7 @@
 prop_ppDiffR (DiffInput le ri) =
     let haskDiff=ppDiff $ getGroupedDiff le ri
         utilDiff= unsafePerformIO (runDiff (unlines le) (unlines ri))
-    in  cover (haskDiff == utilDiff) 90 "exact match" $
+    in  cover 90 (haskDiff == utilDiff) "exact match" $
                 classify (haskDiff == utilDiff) "exact match"
                         (div ((length haskDiff)*100) (length utilDiff) < 110) -- less than 10% bigger
     where
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<tr><td><span title='2021-01-05 14:36:15 +0200'>2021-01-05</span></td><td><a href='/guix/commit/gnu/packages/visidata.scm?id=effacc281c758236bbba9a1f4fd7791baa303a96'>gnu: visidata: Update to 2.1.1.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/visidata.scm (visidata): Update to 2.1.1.

Signed-off-by: Efraim Flashner &lt;efraim@flashner.co.il&gt;
</span></span></td><td>Ryan Prior</td></tr>
<tr><td><span title='2020-12-10 16:40:24 +0200'>2020-12-10</span></td><td><a href='/guix/commit/gnu/packages/visidata.scm?id=d4e3527f78d22d77a62d6e00e179526c37831bc8'>gnu: visidata: Update to 2.1.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/visidata.scm (visidata): Update to 2.1.

Signed-off-by: Efraim Flashner &lt;efraim@flashner.co.il&gt;
</span></span></td><td>Ryan Prior</td></tr>
<tr><td><span title='2020-10-21 19:19:34 +0200'>2020-10-21</span></td><td><a href='/guix/commit/gnu/packages/visidata.scm?id=0e2f871c65a7a923b56f4fb609b66b4d8c767b21'>gnu: visidata: Update to 2.0.1.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/visidata.scm (visidata): Update to 2.0.1.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Ryan Prior</td></tr>
<span class='msg-tooltip'>* gnu/packages/debian.scm (debianutils): New public variable.
</span></span></td><td>Marius Bakke</td></tr>