Track pending ANSI reset codes to preserve correct carry-over behavior

Previously a boolean flag (`matched_reset`) was used, which failed when multiple
reset codes appeared. Replacing it with a counter (`pending_resets`) allows
nested ANSI states to unwind correctly during line wrapping.

Author: onk

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Fixed
 
 * Fix IndexError in `Strings::Wrap.wrap` and correct ANSI color insertion on wrap (@onk)
+* Track unclosed ANSI sequences to preserve correct color state across wraps (@onk)
 
 ## [v0.2.1] - 2021-03-09
 

lib/strings/wrap.rb

@@ -135,24 +135,25 @@ def insert_ansi(string, ansi_stack = [])
       new_stack = []
       output          = string.dup
       length          = string.size
-      matched_reset   = false
+      pending_resets  = 0
       ansi_reset      = Strings::ANSI::RESET
 
       # Reversed so that string index don't count ansi
       ansi_stack.reverse_each do |ansi|
         if ansi[0] =~ /#{Regexp.quote(ansi_reset)}/
-          matched_reset = true
+          pending_resets += 1
           output.insert(ansi[1], ansi_reset)
           next
-        elsif !matched_reset # ansi without reset
-          matched_reset = false
+        elsif pending_resets.zero? # ansi without reset
           new_stack.unshift([ansi[0], 0]) # carry over ANSI to the start of next line preserving order
           next if ansi[1] == length
           if output.end_with?(NEWLINE)
             output.insert(-2, ansi_reset)
           else
             output.insert(-1, ansi_reset) # add reset at the end
           end
+        else
+          pending_resets -= 1
         end
 
         output.insert(ansi[1], ansi[0])