fix scanner initialization, add test

R=r
DELTA=27  (25 added, 0 deleted, 2 changed)
OCL=26798
CL=26798

diff --git a/src/lib/go/scanner.go b/src/lib/go/scanner.go
index 41ce78218b0307d398dcf18fa13a331150f60262..8b51a3e49801e0e75daea5ae3fd92bb3fa794363 100644 (file)
--- a/src/lib/go/scanner.go
+++ b/src/lib/go/scanner.go
@@ -76,10 +76,12 @@ func (S *Scanner) next() {
 // white space and ignored.
 //
 func (S *Scanner) Init(src []byte, err ErrorHandler, scan_comments bool) {
+       // Explicitly initialize all fields since a scanner may be reused.
        S.src = src;
        S.err = err;
        S.scan_comments = scan_comments;
-       S.pos.Line = 1;
+       S.pos = token.Position{0, 1, 0};
+       S.offset = 0;
        S.next();
 }
 

diff --git a/src/lib/go/scanner_test.go b/src/lib/go/scanner_test.go
index 2042b191f821e51997dc14accc17905fd0f9cbf3..bbe0b7602d96c97fde87965c7fbba3e1e1bbd498 100644 (file)
--- a/src/lib/go/scanner_test.go
+++ b/src/lib/go/scanner_test.go
@@ -176,7 +176,8 @@ func NewlineCount(s string) int {
 }
 
 
-func Test(t *testing.T) {
+// Verify that calling Scan() provides the correct results.
+func TestScan(t *testing.T) {
        // make source
        var src string;
        for i, e := range tokens {
@@ -223,3 +224,25 @@ func Test(t *testing.T) {
                }
        );
 }
+
+
+// Verify that initializing the same scanner more then once works correctly.
+func TestInit(t *testing.T) {
+       var s scanner.Scanner;
+
+       // 1st init
+       s.Init(io.StringBytes("if true { }"), &TestErrorHandler{t}, false);
+       s.Scan();  // if
+       s.Scan();  // true
+       pos, tok, lit := s.Scan();  // {
+       if tok != token.LBRACE {
+               t.Errorf("bad token: got %s, expected %s", tok.String(), token.LBRACE);
+       }
+
+       // 2nd init
+       s.Init(io.StringBytes("go true { ]"), &TestErrorHandler{t}, false);
+       pos, tok, lit = s.Scan();  // go
+       if tok != token.GO {
+               t.Errorf("bad token: got %s, expected %s", tok.String(), token.GO);
+       }
+}