From d1f0ce1d57c22f9729d613bffcee0d85c1d606fe Mon Sep 17 00:00:00 2001
From: Wade Mealing <wmealing@gmail.com>
Date: Wed, 28 Sep 2011 04:15:24 +1000
Subject: [PATCH] Patch to error and fail instead of using all available memory
 then crashing to detect the error condition of an unmatched double quote
 before the end of a file.

I couldn't get it to show nice error messages, so this may not be
the ideal fix.

A test case for this situation has also been added.
---
 src/comp/syntax/parse/lexer.rs                  | 6 ++++++
 src/test/compile-fail/unbalanced-doublequote.rs | 8 ++++++++
 2 files changed, 14 insertions(+)
 create mode 100644 src/test/compile-fail/unbalanced-doublequote.rs

diff --git a/src/comp/syntax/parse/lexer.rs b/src/comp/syntax/parse/lexer.rs
index e36b26c559e98..a1f40ea81c184 100644
--- a/src/comp/syntax/parse/lexer.rs
+++ b/src/comp/syntax/parse/lexer.rs
@@ -490,8 +490,14 @@ fn next_token_inner(rdr: reader) -> token::token {
         ret token::LIT_CHAR(c2);
       }
       '"' {
+	let n = rdr.get_chpos(); 
         rdr.bump();
         while rdr.curr() != '"' {
+            if rdr.is_eof() {
+                rdr.err(#fmt["unterminated double quote string: %s", rdr.get_str_from(n)]);
+                fail;
+            }
+
             let ch = rdr.curr();
             rdr.bump();
             alt ch {
diff --git a/src/test/compile-fail/unbalanced-doublequote.rs b/src/test/compile-fail/unbalanced-doublequote.rs
new file mode 100644
index 0000000000000..098169e85700a
--- /dev/null
+++ b/src/test/compile-fail/unbalanced-doublequote.rs
@@ -0,0 +1,8 @@
+// -*- rust -*-
+
+// error-pattern: unterminated double quote string 
+
+
+fn main() {
+	" 
+}