`hledger add` does not recompute amounts from balance assignments

[dotlambda]

I have a journal file with a transaction whose amounts are only computed based on a balance assignment.
Trying to insert an earlier transaction using hledger add fails because it checks the asserted balance using the same amounts as computed before, rather than the amounts that the balance assignment would imply after the new transaction being inserted.

$ hledger --version
hledger 1.52, linux-x86_64
$ cat hledger.journal
1970-01-02 transaction B
    account1  = 1
    account2
$ hledger add -f hledger.journal
Adding transactions to journal file hledger.journal
Any command line arguments will be used as defaults.
Use tab key to complete, readline keys to edit, enter to accept defaults.
An optional (CODE) may follow transaction dates.
An optional ; COMMENT may follow descriptions or amounts.
If you make a mistake, enter < at any prompt to go one step backward.
To end a transaction, enter . when prompted.
To quit, enter . at a date prompt or press control-d or control-c.
Date [2026-05-29]: 1970-01-01
Description: transaction A
Using this similar transaction for defaults:
1970-01-02 transaction B
    account1               1 = 1
    account2              -1

Account 1 [account1]: account1
Amount  1 [1]: 1
hledger.journal:2:15:
  | 1970-01-02 transaction B
2 |     account1               1 = 1
  |                              ^^^
  |     account2              -1

Balance assertion failed in account1
In commodity "" at this point, excluding subaccounts, ignoring costs,
the asserted balance is:        1
but the calculated balance is:  2
(difference: -1)
To troubleshoot, check this account's running balance with assertions disabled, eg:
hledger reg -I 'account1$' cur:
Amount  1 [1]:

I tested this with version 1.52 on NixOS.
Note that this bug is similar to one that I've reported before: #2478

[simonmichael]

Strange, I wonder why I can't reproduce:

$ cat d.j
1970-01-02 transaction B
    account1  = 1
    account2
$ hledger-1.52 -f d.j add
...
Date [2026-06-03]: 
Description: 
Using this similar transaction for defaults:
1970-01-02 transaction B
    account1               1 = 1
    account2              -1

Account 1 [account1]: 
Amount  1 [1]: 1
Account 2 [account2]: 
Amount  2 [-1]: 
Account 3 (or . or enter to finish this transaction): 
2026-06-03
    account1               1
    account2              -1

Save this transaction to the journal ? [y]: 
Saved.

[simonmichael]

I have changed "assertion" to "assignment" just to keep the terminology straight.

[simonmichael]

This is mentioned at https://hledger.org/1.52/hledger.html#add-and-balance-assignments with a workaround. I'm not sure if anything needs to be done ?

[dotlambda]

Strange, I wonder why I can't reproduce

The transaction you add needs to have an earlier date than the existing one.

[dotlambda]

add normally won't let you add a new posting which is dated earlier than an existing balance assignment.

That's weird, I didn't have to pass -I but was allowed to add an earlier transaction.
EDIT: Never mind, by "won't let you" you mean it will fail the balance assertion. So yes, it is mentioned in the docs.
Would it be hard to make add recompute the amounts for the assignment?

[simonmichael]

Ah, thanks. Reproduced now.

I don't remember why exactly it's allowed only with -I, but yes I think it was hard, in the sense of some kind of fundamental dependency issue that prevents doing this reliably. I would probably just clarify the doc a little, but someone might like to look into it again.

[simonmichael]

Or maybe it was just tricky to implement.

I have clarified the doc a little: https://hledger.org/dev/hledger.html#add-and-balance-assignments