Search for lockfile in manifest-ancestor-paths

src/dependencies.rs

@@ -15,6 +15,15 @@ where
     res
 }
 
+fn find_lockfile(base: &path::Path) -> io::Result<path::PathBuf> {
+    base.ancestors()
+        .find_map(|p| {
+            let lockfile = p.join("Cargo.lock");
+            lockfile.exists().then(|| lockfile.to_owned())
+        })
+        .ok_or(io::Error::other("Cargo.lock not found"))
+}
+
 #[cfg(feature = "dependency-tree")]
 struct Dependencies {
     deps: Vec<(String, String)>,
@@ -68,7 +77,7 @@ pub fn write_dependencies(manifest_location: &path::Path, mut w: &fs::File) -> i
     use io::{Read, Write};
 
     let mut lock_buf = String::new();
-    fs::File::open(manifest_location.join("Cargo.lock"))?.read_to_string(&mut lock_buf)?;
+    fs::File::open(find_lockfile(manifest_location)?)?.read_to_string(&mut lock_buf)?;
     let lockfile = lock_buf.parse().expect("Failed to parse lockfile");
 
     let dependencies = Dependencies::new(&lockfile);
@@ -138,7 +147,7 @@ pub fn write_dependencies(manifest_location: &path::Path, mut w: &fs::File) -> i
     use io::{Read, Write};
 
     let mut lock_buf = String::new();
-    fs::File::open(manifest_location.join("Cargo.lock"))?.read_to_string(&mut lock_buf)?;
+    fs::File::open(find_lockfile(manifest_location)?)?.read_to_string(&mut lock_buf)?;
     let lockfile: cargo_lock::Lockfile = lock_buf.parse().expect("Failed to parse lockfile");
 
     let deps = package_names(&lockfile.packages);

tests/testbox_tests.rs

@@ -68,6 +68,8 @@ fn main() {
             .unwrap();
         for (name, content) in self.files {
             let fname = self.root.path().join(name);
+            assert!(fname.is_absolute());
+            fs::create_dir_all(fname.parent().unwrap()).unwrap();
             let mut file = fs::File::create(fname)?;
             file.write_all(&content)?;
         }
@@ -308,6 +310,43 @@ fn main() {
     p.create_and_run(&[]);
 }
 
+#[test]
+fn simple_workspace() {
+    let mut p = Project::new();
+    let built_root = get_built_root();
+
+    p.add_file("Cargo.toml", "[workspace]\nmembers = ['foobar']");
+    p.add_file(
+        "foobar/Cargo.toml",
+        format!(
+            r#"[package]
+name = "foobar"
+version = "5.6.7"
+build = "build.rs"
+
+[build-dependencies]
+built = {{ path = {:?} }}"#,
+            &built_root
+        ),
+    );
+    p.add_file(
+        "foobar/build.rs",
+        "fn main() { built::write_built_file().unwrap(); }",
+    );
+    p.add_file(
+        "foobar/src/main.rs",
+        r#"
+mod built_info {
+    include!(concat!(env!("OUT_DIR"), "/built.rs"));
+}
+fn main() {
+    assert_eq!(built_info::PKG_VERSION, "5.6.7");
+}
+"#,
+    );
+    p.create_and_run(&[]);
+}
+
 #[test]
 fn full_testbox() {
     let mut p = Project::new();