Patching support for crate universe local vendoring

crate_universe/Cargo.toml

@@ -24,7 +24,7 @@ anyhow = "1.0.75"
 camino = "1.1.6"
 cargo_metadata = "0.18.1"
 cargo_toml = "0.19.2"
-cargo-lock = "9.0.0"
+cargo-lock = "10.0.0"
 cargo-platform = "0.1.4"
 cfg-expr = "0.15.5"
 clap = { version = "4.3.11", features = ["derive", "env"] }

crate_universe/private/crates_vendor.bzl

@@ -498,12 +498,35 @@ directory next to where the target is defined. To run it, simply call:
 bazel run //3rdparty:crates_vendor
 ```
 
+### Patching
+
+If you need to replace crates in your third_party dependency tree with forks, the `patch` section can be used in your cargo manifest:
+
+```toml
+[patch.crates-io]
+fuse3 = { path = "forks/fuse3" }
+```
+
+A build file for the patched crate will still be generated under the vendor path
+(such as `crates/fuse3-0.6.1/BUILD.bazel`), but `cargo vendor` will NOT download the
+crate to that location, and the generated BUILD file will point to your copy. For this
+to work, you need to define the following filegroups in your patch crate's BUILD.bazel:
+`:srcs`, `:crate_root`, `:compile_data`, and (if the crate has a build script)
+`:build_script_crate_root`. See the
+[patching example](https://github.com/bazelbuild/rules_rust/tree/main/examples/crate_universe/vendor_local_patching)
+for an example of what those BUILD files look like.
+
+This feature can also be used to avoid vendoring source code for crates that you never
+actually use for the platforms you're targeting. In that case you don't need an extra
+BUILD file, just crate a empty/stub Cargo.toml and `lib.rs`, and list the path to that
+in your `patch` section.
+
 <a id="#crates_vendor_repinning_updating_dependencies"></a>
 
 ### Repinning / Updating Dependencies
 
 Repinning dependencies is controlled by both the `CARGO_BAZEL_REPIN` environment variable or the `--repin`
-flag to the `crates_vendor` binary. To update dependencies, simply add the flag ro your `bazel run` invocation.
+flag to the `crates_vendor` binary. To update dependencies, simply add the flag to your `bazel run` invocation.
 
 ```shell
 bazel run //3rdparty:crates_vendor -- --repin

crate_universe/src/cli/vendor.rs

@@ -125,6 +125,7 @@ pub fn vendor(opt: VendorOptions) -> Result<()> {
     // Generate a splicer for creating a Cargo workspace manifest
     let splicer = Splicer::new(PathBuf::from(temp_dir.as_ref()), splicing_manifest)
         .context("Failed to create splicer")?;
+    // std::mem::forget(temp_dir);
 
     let cargo = Cargo::new(opt.cargo, opt.rustc.clone());
 

crate_universe/src/context.rs

@@ -61,7 +61,7 @@ impl Context {
             .map(|annotation| {
                 let context = CrateContext::new(
                     annotation,
-                    &annotations.metadata.packages,
+                    &annotations.metadata,
                     &annotations.lockfile.crates,
                     &annotations.pairred_extras,
                     &annotations.metadata.workspace_metadata.tree_metadata,