nitcc: lexer do not crash on empty input stream

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

diff --git a/contrib/nitcc/tests/sav/empty.input2.res b/contrib/nitcc/tests/sav/empty.input2.res
index f22973a..b0ab3c5 100644 (file)
--- a/contrib/nitcc/tests/sav/empty.input2.res
+++ b/contrib/nitcc/tests/sav/empty.input2.res
@@ -1,2 +1,2 @@
-NLexerError@(1:1-1:1)=''
+NParserError@(1:1-1:1)=''
 Nodes

diff --git a/lib/nitcc_runtime.nit b/lib/nitcc_runtime.nit
index ce591b9..20342e6 100644 (file)
--- a/lib/nitcc_runtime.nit
+++ b/lib/nitcc_runtime.nit
@@ -192,20 +192,22 @@ abstract class Lexer
                        end
                        var next = state.trans(c)
                        if next == null then
-                               if last_state == null then
-                                       var token = new NLexerError
-                                       var position = new Position(pos_start, pos, line_start, line, col_start, col)
-                                       token.position = position
-                                       token.text = text.substring(pos_start, pos-pos_start+1)
-                                       res.add token
-                                       break
+                               if pos_start < length then
+                                       if last_state == null then
+                                               var token = new NLexerError
+                                               var position = new Position(pos_start, pos, line_start, line, col_start, col)
+                                               token.position = position
+                                               token.text = text.substring(pos_start, pos-pos_start+1)
+                                               res.add token
+                                               break
+                                       end
+                                       var position = new Position(pos_start, pos_end, line_start, line_end, col_start, col_end)
+                                       var token = last_state.make_token(position, text.substring(pos_start, pos_end-pos_start+1))
+                                       if token != null then res.add(token)
                                end
-                               var position = new Position(pos_start, pos_end, line_start, line_end, col_start, col_end)
-                               var token = last_state.make_token(position, text.substring(pos_start, pos_end-pos_start+1))
-                               if token != null then res.add(token)
                                if pos >= length then
-                                       token = new NEof
-                                       position = new Position(pos, pos, line, line, col, col)
+                                       var token = new NEof
+                                       var position = new Position(pos, pos, line, line, col, col)
                                        token.position = position
                                        token.text = ""
                                        res.add token