rustpkg: Change this example to show how to do a custom build

src/librustpkg/testsuite/pass/fancy-lib/pkg.rs

@@ -8,10 +8,16 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+use core::run;
+
 pub fn main() {
     let cwd = os::getcwd();
     debug!("cwd = %s", cwd.to_str());
     let file = io::file_writer(&Path(~"fancy-lib/build/generated.rs"),
                                [io::Create]).get();
     file.write_str("pub fn wheeeee() { for [1, 2, 3].each() |_| { assert!(true); } }");
+
+    // now compile the crate itself
+    run::run_program("rustc", ~[~"fancy-lib/fancy-lib.rs", ~"--lib",
+                                ~"-o", ~"fancy-lib/build/fancy_lib"]);
 }