bal: --budget: don't always convert to cost

And don't show a percentage when budgeted and actual amounts are in
different commodities.

hledger-lib/Hledger/Reports/BudgetReport.hs

@@ -308,19 +308,19 @@ budgetReportAsText ropts@ReportOpts{..} budgetr@(PeriodicReport ( _, rows, _)) =
                        (showbudgetamt budget)
 
     -- | Calculate the percentage of actual change to budget goal to show, if any.
-    -- Both amounts are converted to cost, if possible, before comparing.
+    -- If valuing at cost, both amounts are converted to cost before comparing.
     -- A percentage will not be shown if:
     -- - actual or goal are not the same, single, commodity
     -- - the goal is zero
     percentage :: Change -> BudgetGoal -> Maybe Percentage
     percentage actual budget =
-      case (toCost actual, toCost budget) of
+      case (maybecost $ normaliseMixedAmount actual, maybecost $ normaliseMixedAmount budget) of
         (Mixed [a], Mixed [b]) | (acommodity a == acommodity b || isZeroAmount a) && not (isZeroAmount b) 
             -> Just $ 100 * aquantity a / aquantity b
-        _   -> Nothing
+        _   -> -- trace (pshow $ (maybecost actual, maybecost budget))  -- debug missing percentage
+               Nothing
       where
-        toCost = normaliseMixedAmount . costOfMixedAmount 
+        maybecost = if valuationTypeIsCost ropts then costOfMixedAmount else id
-
     showamt :: MixedAmount -> String
     showamt | color_    = cshowMixedAmountOneLineWithoutPrice
             | otherwise = showMixedAmountOneLineWithoutPrice

tests/budget/budget.test

@@ -31,7 +31,7 @@
 
 
 # 1. Test --budget switch
-$ hledger bal -D -b 2016-12-01 -e 2016-12-04 -f - --budget
+$ hledger -f- bal -D -b 2016-12-01 -e 2016-12-04 --budget
 Budget performance in 2016/12/01-2016/12/03:
 
                   ||           2016/12/01            2016/12/02            2016/12/03 
@@ -45,7 +45,7 @@ Budget performance in 2016/12/01-2016/12/03:
                   ||    0 [            0]     0 [            0]     0 [            0] 
 
 # 2. -E
-$ hledger bal -D -b 2016-12-01 -e 2016-12-04 -f - --budget -E
+$ hledger -f- bal -D -b 2016-12-01 -e 2016-12-04 --budget -E
 Budget performance in 2016/12/01-2016/12/03:
 
                   ||           2016/12/01            2016/12/02            2016/12/03 
@@ -95,15 +95,15 @@ Budget performance in 2016/12/01-2016/12/03:
     expenses:leisure  $15
     assets:cash
 
-$ hledger bal -D -b 2016-12-01 -e 2016-12-04 -f - --budget
+$ hledger -f- bal -D -b 2016-12-01 -e 2016-12-04 --budget
 Budget performance in 2016/12/01-2016/12/03:
 
                   ||                 2016/12/01                    2016/12/02                  2016/12/03 
 ==================++======================================================================================
  assets           ||       $-15 [  60% of $-25]          $-26 [ 104% of $-25]        $-51 [ 204% of $-25] 
  assets:cash      ||       $-15 [  60% of $-25]          $-26 [ 104% of $-25]        $-51 [ 204% of $-25] 
- expenses         ||        £10 [  60% of  $25]    $5, 20 CAD [ 104% of  $25]         $51 [ 204% of  $25] 
+ expenses         ||        £10 [          $25]    $5, 20 CAD [          $25]         $51 [ 204% of  $25] 
- expenses:food    ||        £10 [ 150% of  $10]        20 CAD [ 210% of  $10]         $11 [ 110% of  $10] 
+ expenses:food    ||        £10 [          $10]        20 CAD [          $10]         $11 [ 110% of  $10] 
  expenses:leisure ||          0 [   0% of  $15]            $5 [  33% of  $15]           0 [   0% of  $15] 
 ------------------++--------------------------------------------------------------------------------------
                   ||  $-15, £10 [            0]  $-21, 20 CAD [            0]           0 [            0]