print: be sure to value all postings; -V/-X/--value now imply -x

Previously -B implied -x; now any of the valuation flags do.
This avoids a bug where print -V of a transaction with an implicit
commodity conversion would convert only some of its postings to value.

Also, more valuation tests.

hledger/Hledger/Cli/Commands/Print.hs

@@ -15,6 +15,7 @@ module Hledger.Cli.Commands.Print (
 )
 where
 
+import Data.Maybe (isJust)
 import Data.Text (Text)
 import qualified Data.Text as T
 import System.Console.CmdArgs.Explicit
@@ -59,14 +60,18 @@ printEntries opts@CliOpts{reportopts_=ropts} j = do
   writeOutput opts $ render $ entriesReport ropts' q j
 
 entriesReportAsText :: CliOpts -> EntriesReport -> String
-entriesReportAsText opts = concatMap (showTransaction . gettxn)
+entriesReportAsText opts = concatMap (showTransaction . whichtxn)
   where
-    gettxn | useexplicittxn = id                   -- use fully inferred amounts & txn prices
-           | otherwise      = originalTransaction  -- use original as-written amounts/txn prices
-    -- Original vs inferred transactions/postings were causing problems here, disabling -B (#551).
-    -- Use the explicit one if -B or -x are active.
-    -- This passes tests; does it also mean -B sometimes shows missing amounts unnecessarily ?
-    useexplicittxn = boolopt "explicit" (rawopts_ opts) || (valuationTypeIsCost $ reportopts_ opts)
+    whichtxn
+      -- With -x, use the fully-inferred txn with all amounts & txn prices explicit.
+      | boolopt "explicit" (rawopts_ opts)
+        -- Or also, if any of -B/-V/-X/--value are active.
+        -- Because of #551, and because of print -V valuing only one
+        -- posting when there's an implicit txn price.
+        -- So -B/-V/-X/--value implies -x. Is this ok ?
+        || (isJust $ value_ $ reportopts_ opts) = id
+      -- By default, use the original as-written-in-the-journal txn.
+      | otherwise = originalTransaction
 
 -- Replace this transaction's postings with the original postings if any, but keep the
 -- current possibly rewritten account names.

hledger/Hledger/Cli/Commands/Print.md

@@ -41,6 +41,7 @@ Similarly, when a transaction price is implied but not written, it will not appe
 You can use the `-x`/`--explicit` flag to make all amounts and transaction prices explicit, 
 which can be useful for troubleshooting or for making your journal more readable and
 robust against data entry errors.
+`-x` is also implied by using any of `-B`,`-V`,`-X`,`--value`.
 
 Note, `-x`/`--explicit` will cause postings with a multi-commodity amount
 (these can arise when a multi-commodity transaction has an implicit amount)

tests/journal/valuation.test

@@ -566,3 +566,68 @@ Budget performance in 2000q1, valued at 2000-01-15:
  a || 5 B [  50% of 10 B]  5 B [  50% of 10 B]  5 B [  50% of 10 B]  15 B [  50% of 30 B]  5 B [  50% of 10 B] 
 ---++----------------------------------------------------------------------------------------------------------
    || 5 B [  50% of 10 B]  5 B [  50% of 10 B]  5 B [  50% of 10 B]  15 B [  50% of 30 B]  5 B [  50% of 10 B] 
+
+# 50. --value=then with --historical. How is the starting total valued ?
+# Currently not supported.
+<
+P 2020-01-01 A 1 B
+P 2020-02-01 A 2 B
+P 2020-03-01 A 3 B
+P 2020-04-01 A 4 B
+
+2020-01-01
+   (a)  1 A
+
+2020-02-01
+   (a)  1 A
+
+2020-03-01
+   (a)  1 A
+
+2020-04-01
+   (a)  1 A
+
+$ hledger -f- reg --value=then -b 2020-03 -H
+>2 /not yet implemented/
+>=1
+
+# 51. --value=then with a report interval. How are the summary amounts valued ?
+# Currently each interval's unvalued sum is valued on its first day.
+<
+P 2020-01-01 A 1 B
+P 2020-02-01 A 2 B
+P 2020-03-01 A 3 B
+P 2020-04-01 A 4 B
+
+2020-01-01
+   (a)  1 A
+
+2020-02-01
+   (a)  1 A
+
+2020-03-01
+   (a)  1 A
+
+2020-04-01
+   (a)  1 A
+
+$ hledger -f- reg --value=then -Q
+2020q1                  a                                      3 B           3 B
+2020q2                  a                                      4 B           7 B
+>=0
+
+# 52. print --value should affect all postings, including when there's an implicit transaction price
+<
+P 2020-01-01 A 1 C
+P 2020-01-01 B 1 C
+
+2020-01-01
+   a   1 A
+   b  -1 B
+
+$ hledger -f- print -V
+2020-01-01
+    a             1 C
+    b            -1 C
+
+>=0