C-c C-p: bad suggestion with inline math, e.g. ($20 + $10)

[Bodertz]

ledger-mode-version: 3.0.0

2019-09-21 Store - Buy Two Get One 1/2 Off!
    Expenses:Items  (2 * $60.00 + $30.00)
    Equity:Example

Place point over 'Expenses:Items' and do M-x ledger-display-balance-at-point (or C-c C-p).

Look at the minibuffer:

Result:

Account balance to show (Expenses:Items  (2 \* \$60\.00 \+ \$30\.00):

Press RET.
Ledger error: Error: Missing ')'

Expected Result:

Account balance to show (Expenses:Items):

Press RET.

         $150.00                   0                 Expenses:Items

ledger-display-balance-at-point eventually calls ledger-read-account-with-prompt:

 (let* ((account (ledger-read-account-with-prompt "Account balance to show"))
        ...))

(defun ledger-read-account-with-prompt (prompt)
  "Read an account from the minibuffer with PROMPT."
  (let* ((context (ledger-context-at-point))
         (account (ledger-context-field-value context 'account)))
    (ledger-completing-read-with-default prompt
                                         (when account
                                           (regexp-quote account))
                                         (ledger-accounts-list))))

Note that the result of (ledger-accounts-list) is correct; it is merely the default suggestion given by (ledger-context-field-value context 'account) that is wrong.

Running ledger-context-at-point on the "Expenses" line gives as the result:

(acct-transaction indent ((indent "   " 45) (status nil nil) (account "Expenses:Items  (2 * $60.00 + $30.00" 49)))

I think this means that a regular expression failed to match something,
and so the 'account' regexp matched more than it should have.

I think the issue lies in the constant ledger-line-config,
which is referred to by the function ledger-extract-context-info,
which is called by the function ledger-context-at-point,
which is called by the function ledger-context-field-info,
which is called by the function ledger-context-field-value,
which is called by the function ledger-read-account-with-prompt,
which, finally, is called by ledger-display-balance-at-point.

There's a whole big thing of regex matching here which I don't understand, and I'm not getting much further than this.

[Bodertz]

I noticed Issue #158 and PR #161. The fix does not appear to help here.

I kinda figured it would, so I might have been going down the wrong path here.