Test fetching from alt registry

Author: l4l

tests/integration/crates_alt.rs

@@ -0,0 +1,14 @@
+use failure::Error;
+use rustwide::Crate;
+
+const INDEX_URL: &str = "https://github.com/rust-lang/staging.crates.io-index";
+
+#[test]
+fn test_fetch() -> Result<(), Error> {
+    let workspace = crate::utils::init_workspace()?;
+
+    let krate = Crate::registry(INDEX_URL, "foo", "0.4.0");
+    krate.fetch(&workspace)?;
+
+    Ok(())
+}

tests/integration/mod.rs

@@ -1,2 +1,3 @@
+mod crates_alt;
 mod crates_git;
 mod purge_caches;