lang/beancount: fix config & more electricity

+ Adds electric alignment of amounts on RET
+ Fixes all of beancount's config (which was running because the package
  is called beancount, not beancount-mode)
+ Fixes flood of "invalid face org-level-N" warnings
+ Fixes beancount-electric-currency for appending currency to unlabelled
  amounts. Also enables this to fall back to first operating_currency in
  document, in available
+ Binds TAB to beancount-outline-cycle on outline heading, otherwise
  indent-according-to-mode. No need for completion popup when company
  already provides this.

modules/lang/beancount/config.el

@@ -1,6 +1,6 @@
 ;;; lang/beancount/config.el -*- lexical-binding: t; -*-
 
-(use-package! beancount-mode
+(use-package! beancount
   :mode "\\.beancount\\'"
   :init
   (add-hook 'beancount-mode-hook #'outline-minor-mode)
@@ -10,13 +10,33 @@
                  '("\\.beancount\\'" all-the-icons-material "attach_money" :face all-the-icons-lblue))
     (add-to-list 'all-the-icons-mode-icon-alist
                  '(beancount-mode all-the-icons-material "attach_money" :face all-the-icons-lblue)))
+
+  ;; TODO PR this upstream
+  (defadvice! +beancount--fix-faces-a ()
+    "`beancount-outline-face' returns org-level-N faces for beancount-mode's
+font-lock keywords, but there is no guarantee `org' will be loaded when
+beancount-mode is activated. If it is absent, you will see a flood of 'invalid
+face' errors. Just use the outline-N faces to get around this.
+
+This msut be advised *before* beancount-mode loads, because
+`beancount-outline-face' is used at load time."
+    :override #'beancount-outline-face
+    (if outline-minor-mode
+        (let ((level (funcall outline-level)))
+          (if (integerp level)
+              (intern (format "outline-%d" level))))
+      nil))
+
   :config
   (when (featurep! +lsp)
     (add-hook 'beancount-mode-local-vars-hook #'lsp!))
 
   (setq beancount-electric-currency t)
 
   (map! :map beancount-mode-map
+        "TAB" (cmds! (and outline-minor-mode (outline-on-heading-p))
+                     #'beancount-outline-cycle
+                     #'indent-according-to-mode)
         :localleader
         "b" #'+beancount/balance
         "c" #'beancount-check
@@ -26,4 +46,33 @@
         (:prefix ("i" . "insert")
          "a" #'beancount-insert-account
          "p" #'beancount-insert-prices
-         "d" #'beancount-insert-date)))
+         "d" #'beancount-insert-date))
+
+  ;; TODO PR this upstream?
+  (defun +beancount-electric-align-h ()
+    "Align amount in current line to `beancount-number-alignment-column'."
+    (when (and beancount-electric-currency (eq last-command-event ?\n))
+      (save-excursion
+        (forward-line -1)
+        (ignore-errors (beancount-align-to-previous-number)))))
+  (add-hook! 'beancount-mode-hook
+    (add-hook 'post-self-insert-hook #'+beancount-electric-align-h 'append t))
+
+  ;; TODO PR this upstream
+  (defadvice! +beancount--fix-account-currency-a (account)
+    "Fixes `beancount-electric-currency', which could never find the currency
+for the current account. Also allows it to fall back to the operating_currency."
+    :override #'beancount--account-currency
+    (save-excursion
+      (goto-char (point-min))
+      (when (or (re-search-forward
+                 (concat "^" beancount-date-regexp " +open"
+                         "\\s-+" (regexp-quote account)
+                         "\\s-+\\(" beancount-currency-regexp "\\)\\>")
+                 nil t)
+                (re-search-forward
+                 (concat "^option\\s-+\"operating_currency\"\\s-+\"\\("
+                         beancount-currency-regexp
+                         "\\)\"")
+                 nil t))
+        (match-string-no-properties 1)))))