From 059e243b166d994ac8044a7e771d8d0b88b2ace7 Mon Sep 17 00:00:00 2001
From: Elly Jones <elly@leptoquark.net>
Date: Fri, 20 Jan 2012 11:12:03 -0500
Subject: [PATCH] [core] extfmt: support %% to escape a %

---
 src/libcore/core.rs   |  2 +-
 src/libcore/extfmt.rs | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/libcore/core.rs b/src/libcore/core.rs
index 1e48890cfff..93fa3522fdb 100644
--- a/src/libcore/core.rs
+++ b/src/libcore/core.rs
@@ -32,4 +32,4 @@ mod core {
 mod std {
     use std;
     import std::test;
-}
\ No newline at end of file
+}
diff --git a/src/libcore/extfmt.rs b/src/libcore/extfmt.rs
index 61b6ec3c1b4..04600a628a0 100644
--- a/src/libcore/extfmt.rs
+++ b/src/libcore/extfmt.rs
@@ -101,6 +101,7 @@ mod ct {
                 }
                 let curr2 = str::substr(s, i, 1u);
                 if str::eq(curr2, "%") {
+                    buf += curr2;
                     i += 1u;
                 } else {
                     buf = flush_buf(buf, pieces);
@@ -451,6 +452,16 @@ mod rt {
         ret false;
     }
 }
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test_percent() {
+        let s = #fmt["ab%%cd"];
+        assert(s == "ab%cd");
+    }
+}
+
 // Local Variables:
 // mode: rust;
 // fill-column: 78;