diff --git a/rust/src/scanner.rs b/rust/src/scanner.rs
index e3adf0e..9091760 100644
--- a/rust/src/scanner.rs
+++ b/rust/src/scanner.rs
@@ -271,41 +271,53 @@ mod tests {
 
     #[test]
     fn test_scan() {
-        assert_scan_token("(", TokenKind::LeftParen);
+        assert_source_scan("(", TokenKind::LeftParen);
 
-        assert_scan_token("!", TokenKind::Bang);
-        assert_scan_token("!=", TokenKind::BangEqual);
-        assert_scan_token("!a", TokenKind::Bang);
+        assert_source_scan("!", TokenKind::Bang);
+        assert_source_scan("!=", TokenKind::BangEqual);
+        assert_source_scan("!a", TokenKind::Bang);
 
-        assert_scan_token("a", TokenKind::Identifier);
-        assert_scan_token("_a", TokenKind::Identifier);
-        assert_scan_token("a1", TokenKind::Identifier);
+        assert_source_scan("a", TokenKind::Identifier);
+        assert_source_scan("_a", TokenKind::Identifier);
+        assert_source_scan("a1", TokenKind::Identifier);
 
-        assert_scan_token("\"foo\"", TokenKind::String);
+        assert_source_scan("\"foo\"", TokenKind::String);
 
-        assert_scan_token("1a", TokenKind::Number);
-        assert_scan_token("1.1", TokenKind::Number);
+        assert_source_scan("1a", TokenKind::Number);
+        assert_source_scan("1.1", TokenKind::Number);
 
-        assert_scan_token("a", TokenKind::Identifier);
-        assert_scan_token("an", TokenKind::Identifier);
-        assert_scan_token("and", TokenKind::And);
-        assert_scan_token("andy", TokenKind::Identifier);
-        assert_scan_token("false", TokenKind::False);
-        assert_scan_token("fa", TokenKind::Identifier);
+        assert_source_scan("a", TokenKind::Identifier);
+        assert_source_scan("an", TokenKind::Identifier);
+        assert_source_scan("and", TokenKind::And);
+        assert_source_scan("andy", TokenKind::Identifier);
+        assert_source_scan("false", TokenKind::False);
+        assert_source_scan("fa", TokenKind::Identifier);
 
-        assert_scan_token("@", TokenKind::Error);
-        assert_scan_token("", TokenKind::Eof);
+        assert_source_scan("@", TokenKind::Error);
+        assert_source_scan("", TokenKind::Eof);
+    }
+
+    #[test]
+    fn test_multi_scan() {
+        let mut scanner = Scanner::new("()");
+        assert_scan(&mut scanner, TokenKind::LeftParen);
+        assert_scan(&mut scanner, TokenKind::RightParen);
+        assert_scan(&mut scanner, TokenKind::Eof);
     }
 
     #[test]
     fn test_whitespace() {
-        assert_scan_token(" foo", TokenKind::Identifier);
-        assert_scan_token("\tfoo", TokenKind::Identifier);
-        assert_scan_token("//   \n", TokenKind::Eof);
+        assert_source_scan(" foo", TokenKind::Identifier);
+        assert_source_scan("\tfoo", TokenKind::Identifier);
+        assert_source_scan("//   \n", TokenKind::Eof);
     }
 
-    fn assert_scan_token(source: &str, kind: TokenKind) {
+    fn assert_source_scan(source: &str, kind: TokenKind) {
         let mut scanner = Scanner::new(source);
+        assert_scan(&mut scanner, kind);
+    }
+
+    fn assert_scan(scanner: &mut Scanner, kind: TokenKind) {
         let token = scanner.scan().unwrap();
         assert_eq!(token.kind, kind);
     }