From 2f9439f3037c54e635aa6e0426cf5f5f7dc2f359 Mon Sep 17 00:00:00 2001
From: Chris Lemaire <c.lemaire@student.tudelft.nl>
Date: Sat, 3 Dec 2022 19:52:29 +0100
Subject: [PATCH 1/2] Change inheriting valued tags to override

Old behaviour of inheriting tags with values was that tags added to, for
instance, a posting, would be added to the tags, possibly overriding the
tags of the transaction. Or, in other words, the transaction tags were
added to the posting tags, as there was no sense of overriding a tag.

The new behaviour is that tags are now overridden when a lower level
re-uses that tag name. For instance, when defining a transaction with
tag t:v and posting with tag t:v2, only t:v2 remains on the posting,
overriding the transaction tag.

Perhaps it would be desirable to add an option for additive tags over
overriding tags, as it may well be useful at times to add to tags in the
parent.
---
 hledger-lib/Hledger/Data/Journal.hs | 11 ++++++++---
 hledger-lib/Hledger/Data/Posting.hs |  7 ++++++-
 hledger/test/query-tag.test         | 20 ++++++++++++++++++++
 3 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/hledger-lib/Hledger/Data/Journal.hs b/hledger-lib/Hledger/Data/Journal.hs
index 63703d256b5..01df13cb1af 100644
--- a/hledger-lib/Hledger/Data/Journal.hs
+++ b/hledger-lib/Hledger/Data/Journal.hs
@@ -111,7 +111,7 @@ import Control.Monad.State.Strict (StateT)
 import Data.Char (toUpper, isDigit)
 import Data.Default (Default(..))
 import Data.Foldable (toList)
-import Data.List ((\\), find, foldl', sortBy, union, intercalate)
+import Data.List ((\\), find, foldl', sortBy, intercalate)
 import Data.List.Extra (nubSort)
 import qualified Data.Map.Strict as M
 import Data.Maybe (catMaybes, fromMaybe, mapMaybe, maybeToList)
@@ -404,9 +404,14 @@ journalAccountTags Journal{jdeclaredaccounttags} a = M.findWithDefault [] a jdec
 -- | Which tags are in effect for this account, including tags inherited from parent accounts ?
 journalInheritedAccountTags :: Journal -> AccountName -> [Tag]
 journalInheritedAccountTags j a =
-  foldl' (\ts a' -> ts `union` journalAccountTags j a') [] as
+  fst $ foldl'
+    (\(ts, nms) (ts', nms') ->
+      (ts <> filter (\(nm, _) -> nm `S.notMember` nms) ts', nms `S.union` nms'))
+    (ats, S.fromList $ fst <$> ats)
+    asts
   where
-    as = a : parentAccountNames a
+    ats = journalAccountTags j a
+    asts = (\ts -> (ts, S.fromList $ fst <$> ts)) <$> journalAccountTags j <$> parentAccountNames a
 -- PERF: cache in journal ?
 
 -- | Find up to N most similar and most recent transactions matching
diff --git a/hledger-lib/Hledger/Data/Posting.hs b/hledger-lib/Hledger/Data/Posting.hs
index c212fd71475..4c96cb6c262 100644
--- a/hledger-lib/Hledger/Data/Posting.hs
+++ b/hledger-lib/Hledger/Data/Posting.hs
@@ -365,7 +365,12 @@ postingStatus Posting{pstatus=s, ptransaction=mt} = case s of
 
 -- | Tags for this posting including any inherited from its parent transaction.
 postingAllTags :: Posting -> [Tag]
-postingAllTags p = ptags p ++ maybe [] ttags (ptransaction p)
+postingAllTags p = ptags p
+  ++ filter
+       (\(nm, _) -> nm `S.notMember` pTagNames)
+       (maybe [] ttags (ptransaction p))
+  where
+    pTagNames = S.fromList (fst <$> ptags p)
 
 -- | Tags for this transaction including any from its postings.
 transactionAllTags :: Transaction -> [Tag]
diff --git a/hledger/test/query-tag.test b/hledger/test/query-tag.test
index 3c887d3cc80..ec16b2429a2 100644
--- a/hledger/test/query-tag.test
+++ b/hledger/test/query-tag.test
@@ -214,3 +214,23 @@ $ hledger -f- bal -N tag:type=a
 # 21.
 $ hledger -f- reg -w80 tag:type=a
 2022-01-01                      (a:aa)                           1             1
+
+# 22. Postings can override the tags of their parents
+<
+2022-11-17 Aldi
+    ; concerns: me
+    Assets               -30 €
+    Costs:Food            20 €
+    Loaned                10 €  ; concerns: you
+
+$ hledger -f- reg tag:concerns=me --pivot=concerns
+2022-11-17 Aldi                 me                           -30 €         -30 €
+                                me                            20 €         -10 €
+
+# 23. Accounts can override the tags of their parents
+<
+account a    ; atag:A
+account a:b  ; atag:B
+
+$ hledger -f- accounts tag:atag=a
+a

From e9603cd6b210d4da5b06eae1cd126fbcffd23988 Mon Sep 17 00:00:00 2001
From: Chris Lemaire <c.lemaire@student.tudelft.nl>
Date: Mon, 16 Jan 2023 20:43:30 +0100
Subject: [PATCH 2/2] Add tests suggested by @lukasbestle

---
 hledger/test/query-tag.test | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/hledger/test/query-tag.test b/hledger/test/query-tag.test
index ec16b2429a2..f490d07b510 100644
--- a/hledger/test/query-tag.test
+++ b/hledger/test/query-tag.test
@@ -234,3 +234,30 @@ account a:b  ; atag:B
 
 $ hledger -f- accounts tag:atag=a
 a
+
+# 24. Transactions can override the tags of used accounts
+<
+account a    ; atag:A
+account a:b  ; atag:B
+2023-01-01 Test
+    ; atag:C
+    (a:b)  10 €
+
+$ hledger -f- bal --pivot=atag
+                10 €  C
+--------------------
+                10 €
+
+# 25. Postings can override the tags of their accounts
+<
+account a    ; atag:A
+account a:b  ; atag:B
+
+2023-01-01 Test
+    ; atag:C
+    (a:b)  10 €  ; atag:D
+
+$ hledger -f- bal --pivot=atag
+                10 €  D
+--------------------
+                10 €