highlight: add `first_line` and `last_line`

Signed-off-by: Jean Privat <jean@pryen.org>

diff --git a/src/highlight.nit b/src/highlight.nit
index 78d7a23..c44773c 100644 (file)
--- a/src/highlight.nit
+++ b/src/highlight.nit
@@ -54,6 +54,15 @@ class HighlightVisitor
        # Used to print parts of the source betwen tokens of the AST
        private var pos = 0
 
+       # The line position in the source file.
+       private var line_pos = 0
+
+       # The first line to generate, null if start at the first line
+       var first_line: nullable Int writable = null
+
+       # The last line to generate, null if finish at the last line
+       var last_line: nullable Int writable = null
+
        init
        do
                html.add_class("nitcode")
@@ -77,7 +86,9 @@ class HighlightVisitor
 
                # Add text between `last_token` and `node`
                var pstart = node.location.pstart
-               if pos < pstart then
+               var line_start = node.location.line_start
+               var line_end = node.location.line_end
+               if pos < pstart and (first_line == null or first_line <= line_start) and (last_line == null or last_line >= line_end) then
                        var text = node.location.file.string.substring(pos, pstart-pos)
                        token_head.append(text)
                        #node.debug("WRT: {token_head.classes} << '{text.escape_to_c}' ")
@@ -261,6 +272,12 @@ redef class Token
        # Use `empty_tag` to create the tag ; then fill it and add it to the html
        redef fun accept_highlight_visitor(v)
        do
+               var fl = v.first_line
+               if fl != null and fl > location.line_start then return
+
+               var ll = v.last_line
+               if ll != null and ll < location.line_end then return
+
                var n = make_tag(v)
                if n.attrs.is_empty and n.classes.is_empty then
                        for c in n.children do