lib, print: rename --new's save files to .latest.*, easier to manage

hledger-lib/Hledger/Read.hs

@@ -261,7 +261,7 @@ tryReaders readers mrulesfile assrt path t = firstSuccessOrFirstError [] readers
     path' = fromMaybe "(string)" path
 
 
---- New versions of readJournal* with easier arguments, and --new/last-seen handling.
+--- New versions of readJournal* with easier arguments, and support for --new.
 
 readJournalFilesWithOpts :: InputOpts -> [FilePath] -> IO (Either String Journal)
 readJournalFilesWithOpts iopts =
@@ -282,21 +282,60 @@ readJournalFileWithOpts iopts prefixedfile = do
   case ej of
     Left e  -> return $ Left e
     Right j | new_ iopts -> do
-      lastdates <- lastSeen f
+      ds <- previousLatestDates f
-      let (newj, newlastdates) = journalFilterSinceLastDates lastdates j
+      let (newj, newds) = journalFilterSinceLatestDates ds j
-      when (not $ null newlastdates) $ saveLastSeen newlastdates f
+      when (not $ null newds) $ saveLatestDates newds f
       return $ Right newj
     Right j -> return $ Right j
 
--- | Given zero or more date values (all the same, representing the
+-- A "LatestDates" is zero or more copies of the same date,
+-- representing the latest transaction date read from a file,
+-- and how many transactions there were on that date.
+type LatestDates = [Day]
+
+-- | Get all instances of the latest date in an unsorted list of dates.
+-- Ie, if the latest date appears once, return it in a one-element list,
+-- if it appears three times (anywhere), return three of it.
+latestDates :: [Day] -> LatestDates
+latestDates = headDef [] . take 1 . group . reverse . sort
+
+-- | Remember that these transaction dates were the latest seen when
+-- reading this journal file.
+saveLatestDates :: LatestDates -> FilePath -> IO () 
+saveLatestDates dates f = writeFile (latestDatesFileFor f) $ unlines $ map showDate dates
+
+-- | What were the latest transaction dates seen the last time this 
+-- journal file was read ? If there were multiple transactions on the
+-- latest date, that number of dates is returned, otherwise just one.
+-- Or none if no transactions were read, or if latest dates info is not 
+-- available for this file.
+previousLatestDates :: FilePath -> IO LatestDates
+previousLatestDates f = do
+  let latestfile = latestDatesFileFor f
+  exists <- doesFileExist latestfile
+  if exists
+  then map (parsedate . strip) . lines . strip . T.unpack <$> readFileStrictly latestfile
+  else return []
+
+-- | Where to save latest transaction dates for the given file path.
+-- (.latest.FILE)
+latestDatesFileFor :: FilePath -> FilePath
+latestDatesFileFor f = dir </> ".latest" <.> fname
+  where
+    (dir, fname) = splitFileName f
+
+readFileStrictly :: FilePath -> IO Text
+readFileStrictly f = readFile' f >>= \t -> C.evaluate (T.length t) >> return t
+
+-- | Given zero or more latest dates (all the same, representing the
 -- latest previously seen transaction date, and how many transactions
 -- were seen on that date), remove transactions with earlier dates
 -- from the journal, and the same number of transactions on the
 -- latest date, if any, leaving only transactions that we can assume
--- are newer. Also returns the new last dates of the new journal.
+-- are newer. Also returns the new latest dates of the new journal.
-journalFilterSinceLastDates :: [Day] -> Journal -> (Journal, [Day])
+journalFilterSinceLatestDates :: LatestDates -> Journal -> (Journal, LatestDates)
-journalFilterSinceLastDates [] j       = (j,  latestDates $ map tdate $ jtxns j)
+journalFilterSinceLatestDates [] j       = (j,  latestDates $ map tdate $ jtxns j)
-journalFilterSinceLastDates ds@(d:_) j = (j', ds')
+journalFilterSinceLatestDates ds@(d:_) j = (j', ds')
   where
     samedateorlaterts     = filter ((>= d).tdate) $ jtxns j
     (samedatets, laterts) = span ((== d).tdate) $ sortBy (comparing tdate) samedateorlaterts
@@ -304,41 +343,6 @@ journalFilterSinceLastDates ds@(d:_) j = (j', ds')
     j'                    = j{jtxns=newsamedatets++laterts}
     ds'                   = latestDates $ map tdate $ samedatets++laterts
 
--- | Get all instances of the latest date in an unsorted list of dates.
--- Ie, if the latest date appears once, return it in a one-element list,
--- if it appears three times (anywhere), return three of it.
-latestDates :: [Day] -> [Day]
-latestDates = headDef [] . take 1 . group . reverse . sort
-
--- | Where to save last-seen transactions info for the given file path
--- (.FILE.seen).
-seenFileFor :: FilePath -> FilePath
-seenFileFor f = dir </> fname' <.> "seen"
-  where
-    (dir, fname) = splitFileName f
-    fname' | "." `isPrefixOf` fname = fname
-           | otherwise              = '.':fname 
-
--- | What were the latest transaction dates seen the last time this 
--- journal file was read ? If there were multiple transactions on the
--- latest date, that number of dates is returned, otherwise just one.
--- Or none if no transactions were seen. 
-lastSeen :: FilePath -> IO [Day]
-lastSeen f = do
-  let seenfile = seenFileFor f
-  exists <- doesFileExist seenfile
-  if exists
-  then map (parsedate . strip) . lines . strip . T.unpack <$> readFileStrictly seenfile
-  else return []
-
-readFileStrictly :: FilePath -> IO Text
-readFileStrictly f = readFile' f >>= \t -> C.evaluate (T.length t) >> return t
-
--- | Remember that these transaction dates were the latest seen when
--- reading this journal file.
-saveLastSeen :: [Day] -> FilePath -> IO () 
-saveLastSeen dates f = writeFile (seenFileFor f) $ unlines $ map showDate dates
-
 readJournalWithOpts :: InputOpts -> Maybe FilePath -> Text -> IO (Either String Journal)
 readJournalWithOpts iopts mfile txt =
   tryReadersWithOpts iopts mfile specifiedorallreaders txt

hledger/doc/commands.m4.md

@@ -524,16 +524,18 @@ With `-m`/`--match` and a STR argument, print will show at most one transaction:
 one whose description is most similar to STR, and is most recent. STR should contain at
 least two characters. If there is no similar-enough match, no transaction will be shown.
 
-With `--new`, for each FILE being read, hledger reads (and writes) a special .FILE.seen file in the same directory,
+With `--new`, for each FILE being read, hledger reads (and writes) a special 
-containing the latest transaction date(s) that were seen last time FILE was read.
+.latest.FILE file in the same directory, containing the latest transaction date(s)
-When this file is found, only transactions with newer dates (and new transactions on the latest date) are printed.
+that were seen last time FILE was read. When this file is found, only transactions 
+with newer dates (and new transactions on the latest date) are printed.
 This is useful for ignoring already-seen entries in import data, such as downloaded CSV files.
 Eg:
 ```console
 $ hledger -f bank1.csv print --new
 # shows transactions added since last print --new on this file
 ```
-It assumes that only same-or-newer-dated transactions are added to FILE, and that the order of same-date transactions remains stable.   
+This assumes that transactions added to FILE always have same or increasing dates, 
+and that transactions on the same day do not get reordered.   
 
 The print command also supports 
 [output destination](#output-destination)

hledger/doc/hledger.1

@@ -2140,8 +2140,8 @@ STR should contain at least two characters.
 If there is no similar\-enough match, no transaction will be shown.
 .PP
 With \f[C]\-\-new\f[], for each FILE being read, hledger reads (and
-writes) a special .FILE.seen file in the same directory, containing the
+writes) a special .latest.FILE file in the same directory, containing
-latest transaction date(s) that were seen last time FILE was read.
+the latest transaction date(s) that were seen last time FILE was read.
 When this file is found, only transactions with newer dates (and new
 transactions on the latest date) are printed.
 This is useful for ignoring already\-seen entries in import data, such
@@ -2155,8 +2155,9 @@ $\ hledger\ \-f\ bank1.csv\ print\ \-\-new
 \f[]
 .fi
 .PP
-It assumes that only same\-or\-newer\-dated transactions are added to
+This assumes that transactions added to FILE always have same or
-FILE, and that the order of same\-date transactions remains stable.
+increasing dates, and that transactions on the same day do not get
+reordered.
 .PP
 The print command also supports output destination and CSV output.
 Here\[aq]s an example of print\[aq]s CSV output:

hledger/doc/hledger.1.info

@@ -1713,7 +1713,7 @@ is most recent.  STR should contain at least two characters.  If there
 is no similar-enough match, no transaction will be shown.
 
    With '--new', for each FILE being read, hledger reads (and writes) a
-special .FILE.seen file in the same directory, containing the latest
+special .latest.FILE file in the same directory, containing the latest
 transaction date(s) that were seen last time FILE was read.  When this
 file is found, only transactions with newer dates (and new transactions
 on the latest date) are printed.  This is useful for ignoring
@@ -1722,8 +1722,9 @@ already-seen entries in import data, such as downloaded CSV files.  Eg:
 $ hledger -f bank1.csv print --new
 # shows transactions added since last print --new on this file
 
-   It assumes that only same-or-newer-dated transactions are added to
+   This assumes that transactions added to FILE always have same or
-FILE, and that the order of same-date transactions remains stable.
+increasing dates, and that transactions on the same day do not get
+reordered.
 
    The print command also supports output destination and CSV output.
 Here's an example of print's CSV output:
@@ -2233,51 +2234,51 @@ Node: prices52658
 Ref: #prices52775
 Node: print52818
 Ref: #print52930
-Node: print-unique57726
+Node: print-unique57737
-Ref: #print-unique57854
+Ref: #print-unique57865
-Node: register57922
+Node: register57933
-Ref: #register58051
+Ref: #register58062
-Node: Custom register output62552
+Node: Custom register output62563
-Ref: #custom-register-output62683
+Ref: #custom-register-output62694
-Node: register-match63980
+Node: register-match63991
-Ref: #register-match64116
+Ref: #register-match64127
-Node: rewrite64299
+Node: rewrite64310
-Ref: #rewrite64418
+Ref: #rewrite64429
-Node: stats64487
+Node: stats64498
-Ref: #stats64592
+Ref: #stats64603
-Node: tags65473
+Node: tags65484
-Ref: #tags65573
+Ref: #tags65584
-Node: test65605
+Node: test65616
-Ref: #test65691
+Ref: #test65702
-Node: ADD-ON COMMANDS66059
+Node: ADD-ON COMMANDS66070
-Ref: #add-on-commands66171
+Ref: #add-on-commands66182
-Node: Official add-ons67458
+Node: Official add-ons67469
-Ref: #official-add-ons67600
+Ref: #official-add-ons67611
-Node: api67687
+Node: api67698
-Ref: #api67778
+Ref: #api67789
-Node: ui67830
+Node: ui67841
-Ref: #ui67931
+Ref: #ui67942
-Node: web67989
+Node: web68000
-Ref: #web68080
+Ref: #web68091
-Node: Third party add-ons68126
+Node: Third party add-ons68137
-Ref: #third-party-add-ons68303
+Ref: #third-party-add-ons68314
-Node: diff68438
+Node: diff68449
-Ref: #diff68537
+Ref: #diff68548
-Node: iadd68636
+Node: iadd68647
-Ref: #iadd68752
+Ref: #iadd68763
-Node: interest68835
+Node: interest68846
-Ref: #interest68958
+Ref: #interest68969
-Node: irr69053
+Node: irr69064
-Ref: #irr69153
+Ref: #irr69164
-Node: Experimental add-ons69231
+Node: Experimental add-ons69242
-Ref: #experimental-add-ons69385
+Ref: #experimental-add-ons69396
-Node: autosync69676
+Node: autosync69687
-Ref: #autosync69790
+Ref: #autosync69801
-Node: budget70029
+Node: budget70040
-Ref: #budget70153
+Ref: #budget70164
-Node: chart70219
+Node: chart70230
-Ref: #chart70338
+Ref: #chart70349
-Node: check70409
+Node: check70420
-Ref: #check70513
+Ref: #check70524
 
 End Tag Table

hledger/doc/hledger.1.txt

@@ -1511,7 +1511,7 @@ COMMANDS
        no similar-enough match, no transaction will be shown.
 
        With --new, for each FILE being read, hledger reads (and writes) a spe-
-       cial  .FILE.seen  file  in  the  same  directory, containing the latest
+       cial  .latest.FILE  file  in  the same directory, containing the latest
        transaction date(s) that were seen last time FILE was read.  When  this
        file is found, only transactions with newer dates (and new transactions
        on  the  latest  date)  are  printed.   This  is  useful  for  ignoring
@@ -1520,8 +1520,9 @@ COMMANDS
               $ hledger -f bank1.csv print --new
               # shows transactions added since last print --new on this file
 
-       It assumes that only  same-or-newer-dated  transactions  are  added  to
+       This assumes that transactions  added  to  FILE  always  have  same  or
-       FILE, and that the order of same-date transactions remains stable.
+       increasing  dates,  and  that  transactions  on the same day do not get
+       reordered.
 
        The print command also supports  output  destination  and  CSV  output.
        Here's an example of print's CSV output: