Add host dependency path via -L for cargo_test.

src/cargo/ops/cargo_rustc/compilation.rs

@@ -28,12 +28,12 @@ pub struct Compilation<'cfg> {
     /// Root output directory (for the local package's artifacts)
     pub root_output: PathBuf,
 
-    /// Output directory for rust dependencies
+    /// Output directory for rust dependencies.
+    /// May be for the host or for a specific target.
     pub deps_output: PathBuf,
 
-    /// Library search path for compiler plugins and build scripts
-    /// which have dynamic dependencies.
-    pub plugins_dylib_path: PathBuf,
+    /// Output directory for the rust host dependencies.
+    pub host_deps_output: PathBuf,
 
     /// The path to rustc's own libstd
     pub host_dylib_path: Option<PathBuf>,
@@ -64,7 +64,7 @@ impl<'cfg> Compilation<'cfg> {
             native_dirs: HashSet::new(),  // TODO: deprecated, remove
             root_output: PathBuf::from("/"),
             deps_output: PathBuf::from("/"),
-            plugins_dylib_path: PathBuf::from("/"),
+            host_deps_output: PathBuf::from("/"),
             host_dylib_path: None,
             target_dylib_path: None,
             tests: Vec::new(),
@@ -124,7 +124,7 @@ impl<'cfg> Compilation<'cfg> {
                 -> CargoResult<ProcessBuilder> {
 
         let mut search_path = if is_host {
-            let mut search_path = vec![self.plugins_dylib_path.clone()];
+            let mut search_path = vec![self.host_deps_output.clone()];
             search_path.extend(self.host_dylib_path.clone());
             search_path
         } else {

src/cargo/ops/cargo_rustc/context.rs

@@ -175,7 +175,7 @@ impl<'a, 'cfg> Context<'a, 'cfg> {
             None => {}
         }
 
-        self.compilation.plugins_dylib_path = self.host.deps().to_path_buf();
+        self.compilation.host_deps_output = self.host.deps().to_path_buf();
 
         let layout = self.target.as_ref().unwrap_or(&self.host);
         self.compilation.root_output = layout.dest().to_path_buf();

src/cargo/ops/cargo_test.rs

@@ -149,10 +149,17 @@ fn run_doc_tests(options: &TestOptions,
                 arg.push(rust_dep);
                 p.arg("-L").arg(arg);
             }
+
             for native_dep in compilation.native_dirs.iter() {
                 p.arg("-L").arg(native_dep);
             }
 
+            for &host_rust_dep in &[&compilation.host_deps_output] {
+                let mut arg = OsString::from("dependency=");
+                arg.push(host_rust_dep);
+                p.arg("-L").arg(arg);
+            }
+
             for arg in test_args {
                 p.arg("--test-args").arg(arg);
             }

tests/test.rs

@@ -6,7 +6,7 @@ use std::fs::File;
 use std::io::prelude::*;
 use std::str;
 
-use cargotest::{sleep_ms, is_nightly};
+use cargotest::{sleep_ms, is_nightly, rustc_host};
 use cargotest::support::{project, execs, basic_bin_manifest, basic_lib_manifest, cargo_exe};
 use cargotest::support::paths::CargoPathExt;
 use cargotest::support::registry::Package;
@@ -2782,3 +2782,58 @@ fn publish_a_crate_without_tests() {
     assert_that(p.cargo("test").arg("--package").arg("testless"),
                 execs().with_status(0));
 }
+
+#[test]
+fn find_dependency_of_proc_macro_dependency_with_target() {
+    let workspace = project("workspace")
+        .file("Cargo.toml", r#"
+            [workspace]
+            members = ["root", "proc_macro_dep"]
+        "#)
+        .file("root/Cargo.toml", r#"
+            [project]
+            name = "root"
+            version = "0.1.0"
+            authors = []
+
+            [dependencies]
+            proc_macro_dep = { path = "../proc_macro_dep" }
+        "#)
+        .file("root/src/lib.rs", r#"
+            #[macro_use]
+            extern crate proc_macro_dep;
+
+            #[derive(Noop)]
+            pub struct X;
+        "#)
+        .file("proc_macro_dep/Cargo.toml", r#"
+            [project]
+            name = "proc_macro_dep"
+            version = "0.1.0"
+            authors = []
+
+            [lib]
+            proc-macro = true
+
+            [dependencies]
+            bar = "^0.1"
+        "#)
+        .file("proc_macro_dep/src/lib.rs", r#"
+            extern crate bar;
+            extern crate proc_macro;
+            use proc_macro::TokenStream;
+
+            #[proc_macro_derive(Noop)]
+            pub fn noop(_input: TokenStream) -> TokenStream {
+                "".parse().unwrap()
+            }
+        "#);
+    Package::new("foo", "0.1.0").publish();
+    Package::new("bar", "0.1.0")
+        .dep("foo", "0.1")
+        .file("src/lib.rs", "extern crate foo;")
+        .publish();
+    workspace.build();
+    assert_that(workspace.cargo("test").arg("--all").arg("--target").arg(rustc_host()),
+                execs().with_status(0));
+}