Improve indent algorithm

The new algorithm relies less on returning '-1'. It also supports
metadata

1 files changed, 25 insertions, 6 deletions

diff --git a/indent/beancount.vim b/indent/beancount.vim
index 686cbdc..29d7d9e 100644
--- a/indent/beancount.vim
+++ b/indent/beancount.vim
@@ -9,16 +9,35 @@ if exists("*GetBeancountIndent")
     finish
 endif
 
+function! s:IsDirective(str)
+    return a:str =~ '\v^\s*(\d{4}-\d{2}-\d{2}|pushtag|poptag|option|plugin|include)'
+endfunction
+
+function! s:IsPost(str)
+    return a:str =~ '\v^\s*(Assets|Liabilities|Expenses|Equity|Income):'
+endfunction
+
+function! s:IsMetadata(str)
+    return a:str =~ '\v^\s*\w+:\s'
+endfunction
+
+function! s:IsTransaction(str)
+    return a:str =~ '\v^\s*\d{4}-\d{2}-\d{2}\s+(txn\s+)?\S\s'
+endfunction
+
 function GetBeancountIndent(line_num)
     let this_line = getline(a:line_num)
     let prev_line = getline(a:line_num - 1)
+    " Don't touch comments
+    if this_line =~ '\v^\s*;' | return -1 | endif
     " This is a new directive or previous line is blank.
-    if this_line =~ '\v^\s*\d{4}-\d{2}-\d{2}' || prev_line =~ '^\s*$'
-        return 0
-    endif
-    " Previous line is the beginning of a transaction.
-    if prev_line =~ '\v^\s*\d{4}-\d{2}-\d{2}\s+(txn\s+)?.\s+'
-        return &shiftwidth
+    if prev_line =~ '^\s*$' || s:IsDirective(this_line) | return 0 | endif
+    " Previous line is transaction or this is a posting.
+    if s:IsTransaction(prev_line) || s:IsPost(this_line) | return &sw | endif
+    if s:IsMetadata(this_line)
+        let this_indent = indent(a:line_num - 1)
+        if ! s:IsMetadata(prev_line) | let this_indent += &sw | endif
+        return this_indent
     endif
     return -1
 endfunction