Rollup merge of #141789 - ferrocene:hoverbear/exclude-cargo-home-from-in-tree-consideration, r=clubby789

Exclude `CARGO_HOME` from `generate-copyright` in-tree determination

On Ferrocene, we noticed that in our releases the out-of-tree notices were not being included. When `x.py run generate-copyright` was ran on local development machines, it worked fine.

After some investigations ``@tshepang`` and I determined that the problem was that the cargo registry (located in `CARGO_HOME`) started with the source directory on CI jobs, and was being excluded by this line:

https://github.com/rust-lang/rust/blob/15825b7161f8bd6a3482211fbf6727a52aa1166b/src/tools/generate-copyright/src/cargo_metadata.rs#L85-L88

In Ferrocene's `run.sh` we set `CARGO_HOME` to be `build/cargo-home`: https://github.com/ferrocene/ferrocene/blob/96a45dd9a18c6e54d3cd81750a78fe459fa48af0/ferrocene/ci/run.sh#L34-L46 which caused this issue.

This PR passes the `CARGO_HOME` variable to the `generate-copyright` tool and expands the consideration of in-tree-ness to be aware of `CARGO_HOME`. It is an upstreaming of https://github.com/ferrocene/ferrocene/pull/1491.

## Testing

Run `CARGO_HOME=build/cargo-home ./x.py run generate-copyright` on `master`, then check `build/host/doc/COPYRIGHT` and look for out of tree dependencies (at the bottom).

Then, try running the same command in this branch.

2 files changed, 17 insertions, 5 deletions

diff --git a/src/tools/generate-copyright/src/cargo_metadata.rs b/src/tools/generate-copyright/src/cargo_metadata.rs
index b717bd53eb1..3fae26bda47 100644
--- a/src/tools/generate-copyright/src/cargo_metadata.rs
+++ b/src/tools/generate-copyright/src/cargo_metadata.rs
@@ -46,11 +46,12 @@ pub struct PackageMetadata {
 /// covered it already.
 pub fn get_metadata_and_notices(
     cargo: &Path,
+    cargo_home_path: &Path,
     vendor_path: &Path,
     root_path: &Path,
     manifest_paths: &[PathBuf],
 ) -> Result<BTreeMap<Package, PackageMetadata>, Error> {
-    let mut output = get_metadata(cargo, root_path, manifest_paths)?;
+    let mut output = get_metadata(cargo, cargo_home_path, root_path, manifest_paths)?;
 
     // Now for each dependency we found, go and grab any important looking files
     for (package, metadata) in output.iter_mut() {
@@ -66,6 +67,7 @@ pub fn get_metadata_and_notices(
 /// assume `reuse` has covered it already.
 pub fn get_metadata(
     cargo: &Path,
+    cargo_home_path: &Path,
     root_path: &Path,
     manifest_paths: &[PathBuf],
 ) -> Result<BTreeMap<Package, PackageMetadata>, Error> {
@@ -81,8 +83,11 @@ pub fn get_metadata(
             .manifest_path(manifest_path)
             .exec()?;
         for package in metadata.packages {
-            let manifest_path = package.manifest_path.as_path();
-            if manifest_path.starts_with(root_path) {
+            let package_manifest_path = package.manifest_path.as_path();
+
+            if package_manifest_path.starts_with(root_path)
+                && !package_manifest_path.starts_with(cargo_home_path)
+            {
                 // it's an in-tree dependency and reuse covers it
                 continue;
             }
diff --git a/src/tools/generate-copyright/src/main.rs b/src/tools/generate-copyright/src/main.rs
index d6ed7261b7c..5497db1f5f3 100644
--- a/src/tools/generate-copyright/src/main.rs
+++ b/src/tools/generate-copyright/src/main.rs
@@ -15,6 +15,7 @@ mod cargo_metadata;
 ///
 /// Run `x.py run generate-copyright`
 fn main() -> Result<(), Error> {
+    let cargo_home = env_path("CARGO_HOME")?;
     let dest_file = env_path("DEST")?;
     let libstd_dest_file = env_path("DEST_LIBSTD")?;
     let src_dir = env_path("SRC_DIR")?;
@@ -39,11 +40,17 @@ fn main() -> Result<(), Error> {
         .collect::<Vec<_>>();
 
     // Scan Cargo dependencies
-    let mut collected_cargo_metadata =
-        cargo_metadata::get_metadata_and_notices(&cargo, &vendor_dir, &src_dir, &cargo_manifests)?;
+    let mut collected_cargo_metadata = cargo_metadata::get_metadata_and_notices(
+        &cargo,
+        &cargo_home,
+        &vendor_dir,
+        &src_dir,
+        &cargo_manifests,
+    )?;
 
     let library_collected_cargo_metadata = cargo_metadata::get_metadata_and_notices(
         &cargo,
+        &cargo_home,
         &vendor_dir,
         &src_dir,
         &library_manifests,