don't loop infinitely if a typo spans multiple tokens

This happens because the "default" token gets emitted for each not matched
char resulting in lots of small "default" tokens.

This markdown:

> typu

will result in the token stream
{"default", 2, "default", 3, "default", 4, "default", 5}
and a typo stream with a single entry spanning all of the tokens
{{"typu", 1, 5}}.

Not checking if the typo is longer then the current token leads to an infinite
loop where the typo is always inserted in the new token stream without advancing
the token stream.

1 files changed, 7 insertions, 1 deletions

diff --git a/spellcheck.lua b/spellcheck.lua
index 0627d4d..ebfe660 100644
--- a/spellcheck.lua
+++ b/spellcheck.lua
@@ -203,7 +203,13 @@ local wrap_lex_func = function(old_lex_func)
 
 					-- highlight typo
 					table.insert(new_tokens, vis.lexers.ERROR)
-					table.insert(new_tokens, typo_end + 1)
+					-- the typo spans multiple tokens
+					if token_end < typo_end then
+						table.insert(new_tokens, token_end + 1)
+						i = i + 2
+					else
+						table.insert(new_tokens, typo_end + 1)
+					end
 				end
 			until(not token_end or token_end >= typo_end)
 		end