Improve experience with the flexible target specification

When calculating the output directory filename, only use the "file name"
component of the target triple specified as otherwise the output could be placed
into an odd location.

Closes #1390

diff --git a/src/cargo/ops/cargo_rustc/layout.rs b/src/cargo/ops/cargo_rustc/layout.rs
index 1f6b2e50ec0ff2d1469f8e22d838311799229950..33ea8af692a9ee5b9e382bc89bf04f468defa6d9 100644 (file)
--- a/src/cargo/ops/cargo_rustc/layout.rs
+++ b/src/cargo/ops/cargo_rustc/layout.rs
@@ -69,9 +69,11 @@ pub struct LayoutProxy<'a> {
 impl Layout {
     pub fn new(pkg: &Package, triple: Option<&str>, dest: &str) -> Layout {
         let mut path = pkg.absolute_target_dir();
-        match triple {
-            Some(s) => path.push(s),
-            None => {}
+        // Flexible target specifications often point at filenames, so interpret
+        // the target triple as a Path and then just use the file stem as the
+        // component for the directory name.
+        if let Some(triple) = triple {
+            path.push(Path::new(triple).file_stem().unwrap());
         }
         path.push(dest);
         Layout::at(path)