ledger 2.6-style account name eliding

Ledger/AccountName.hs

@@ -75,3 +75,27 @@ accountNameTreeFrom accts =
           accountsFrom as = [Node a (accountsFrom $ subs a) | a <- as]
           subs = (subAccountNamesFrom accts)
 
+-- | Elide an account name to fit in the specified width.
+-- From the ledger 2.6 news:
+-- 
+-- @
+--   What Ledger now does is that if an account name is too long, it will
+--   start abbreviating the first parts of the account name down to two
+--   letters in length.  If this results in a string that is still too
+--   long, the front will be elided -- not the end.  For example:
+--
+--     Expenses:Cash           ; OK, not too long
+--     Ex:Wednesday:Cash       ; "Expenses" was abbreviated to fit
+--     Ex:We:Afternoon:Cash    ; "Expenses" and "Wednesday" abbreviated
+--     ; Expenses:Wednesday:Afternoon:Lunch:Snack:Candy:Chocolate:Cash
+--     ..:Af:Lu:Sn:Ca:Ch:Cash  ; Abbreviated and elided!
+-- @
+elideAccountName :: Int -> AccountName -> AccountName
+elideAccountName width s = 
+    elideLeft width $ accountNameFromComponents $ elideparts width [] $ accountNameComponents s
+      where
+        elideparts :: Int -> [String] -> [String] -> [String]
+        elideparts width done ss
+          | (length $ accountNameFromComponents $ done++ss) <= width = done++ss
+          | length ss > 1 = elideparts width (done++[take 2 $ head ss]) (tail ss)
+          | otherwise = done++ss

Ledger/RawTransaction.hs

@@ -10,6 +10,7 @@ where
 import Ledger.Utils
 import Ledger.Types
 import Ledger.Amount
+import Ledger.AccountName
 
 
 instance Show RawTransaction where show = showLedgerTransaction
@@ -17,14 +18,9 @@ instance Show RawTransaction where show = showLedgerTransaction
 showLedgerTransaction :: RawTransaction -> String
 showLedgerTransaction t = (showaccountname $ taccount t) ++ " " ++ (showamount $ tamount t) 
     where
-      showaccountname = printf "%-22s" . elideRight 22
+      showaccountname = printf "%-22s" . elideAccountName 22
       showamount = printf "%12s" . showAmountOrZero
 
-elideRight width s =
-    case length s > width of
-      True -> take (width - 2) s ++ ".."
-      False -> s
-
 autofillTransactions :: [RawTransaction] -> [RawTransaction]
 autofillTransactions ts =
     case (length blanks) of

Ledger/Transaction.hs

@@ -15,8 +15,7 @@ import Ledger.Amount
 
 
 instance Show Transaction where 
-    show (Transaction eno d desc a amt) = 
-        unwords [d,desc,a,show amt]
+    show (Transaction eno d desc a amt) = unwords [d,desc,a,show amt]
 
 -- | Convert a 'Entry' to two or more 'Transaction's. An id number
 -- is attached to the transactions to preserve their grouping - it should

Ledger/Utils.hs

@@ -40,6 +40,16 @@ import Text.Regex
 import Text.ParserCombinators.Parsec (parse)
 
 
+elideLeft width s =
+    case length s > width of
+      True -> ".." ++ (reverse $ take (width - 2) $ reverse s)
+      False -> s
+
+elideRight width s =
+    case length s > width of
+      True -> take (width - 2) s ++ ".."
+      False -> s
+
 -- regexps
 
 instance Show Regex where show r = "a Regex"