log: Use writeln!() instead of write!()

This was accidentally left out of the recent logging improvements.

Author: alexcrichton

src/liblog/lib.rs

@@ -195,11 +195,11 @@ impl fmt::Signed for LogLevel {
 
 impl Logger for DefaultLogger {
     fn log(&mut self, record: &LogRecord) {
-        match write!(&mut self.handle,
-                     "{}:{}: {}",
-                     record.level,
-                     record.module_path,
-                     record.args) {
+        match writeln!(&mut self.handle,
+                       "{}:{}: {}",
+                       record.level,
+                       record.module_path,
+                       record.args) {
             Err(e) => fail!("failed to log: {}", e),
             Ok(()) => {}
         }

src/test/run-pass/logging-separate-lines.rs

@@ -0,0 +1,44 @@
+// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// ignore-android
+// ignore-win32
+
+#![feature(phase)]
+
+#[phase(syntax, link)]
+extern crate log;
+
+use std::io::{Process, ProcessConfig};
+use std::os;
+use std::str;
+
+fn main() {
+    let args = os::args();
+    if args.len() > 1 && args[1].as_slice() == "child" {
+        debug!("foo");
+        debug!("bar");
+        return
+    }
+
+    let env = [("RUST_LOG".to_owned(), "debug".to_owned())];
+    let config = ProcessConfig {
+        program: args[0].as_slice(),
+        args: &["child".to_owned()],
+        env: Some(env.as_slice()),
+        ..ProcessConfig::new()
+    };
+    let p = Process::configure(config).unwrap().wait_with_output();
+    assert!(p.status.success());
+    let mut lines = str::from_utf8(p.error.as_slice()).unwrap().lines();
+    assert!(lines.next().unwrap().contains("foo"));
+    assert!(lines.next().unwrap().contains("bar"));
+}
+