[cargo-bazel] Cleanup MetadataGenerator usage

Author: dzbarsky

crate_universe/src/cli/splice.rs

@@ -1,6 +1,8 @@
 //! The cli entrypoint for the `splice` subcommand
 
 use std::path::PathBuf;
+use std::fs::File;
+use std::process::Stdio;
 
 use anyhow::Context;
 use camino::Utf8PathBuf;
@@ -10,7 +12,7 @@ use itertools::Itertools;
 use crate::cli::Result;
 use crate::config::Config;
 use crate::metadata::{
-    write_metadata, Cargo, CargoUpdateRequest, Generator, MetadataGenerator, TreeResolver,
+    Cargo, CargoUpdateRequest, TreeResolver,
 };
 use crate::splicing::{
     generate_lockfile, Splicer, SplicerKind, SplicingManifest, WorkspaceMetadata,
@@ -111,6 +113,7 @@ pub fn splice(opt: SpliceOptions) -> Result<()> {
             &config.supported_platform_triples,
         )
         .context("Failed to generate features")?;
+
     // Write the registry url info to the manifest now that a lockfile has been generated
     WorkspaceMetadata::write_registry_urls_and_feature_map(
         &cargo,
@@ -121,13 +124,19 @@ pub fn splice(opt: SpliceOptions) -> Result<()> {
     )
     .context("Failed to write registry URLs and feature map")?;
 
-    let output_dir = opt.output_dir.clone();
+    // Generate the consumable outputs of the splicing process
+    std::fs::create_dir_all(&opt.output_dir)
+        .with_context(|| format!("Failed to create directories for {}", opt.output_dir.display()))?;
+
+    let metadata_json = File::create(opt.output_dir.join("metadata.json"))?;
 
     // Write metadata to the workspace for future reuse
-    let (cargo_metadata, _) = Generator::new()
-        .with_cargo(cargo.clone())
-        .with_rustc(opt.rustc.clone())
-        .generate(manifest_path.as_path_buf())
+    cargo
+        .metadata_command_with_options(manifest_path.as_path_buf().as_ref(), vec!["--locked".to_owned()])?
+        .cargo_command()
+        .stdout(Stdio::from(metadata_json))
+        .stderr(Stdio::null())
+        .status()
         .context("Failed to generate cargo metadata")?;
 
     let cargo_lockfile_path = manifest_path
@@ -141,14 +150,7 @@ pub fn splice(opt: SpliceOptions) -> Result<()> {
         })?
         .join("Cargo.lock");
 
-    // Generate the consumable outputs of the splicing process
-    std::fs::create_dir_all(&output_dir)
-        .with_context(|| format!("Failed to create directories for {}", &output_dir.display()))?;
-
-    write_metadata(&opt.output_dir.join("metadata.json"), &cargo_metadata)
-        .context("Failed to write metadata")?;
-
-    std::fs::copy(cargo_lockfile_path, output_dir.join("Cargo.lock"))
+    std::fs::copy(cargo_lockfile_path, opt.output_dir.join("Cargo.lock"))
         .context("Failed to copy lockfile")?;
 
     if let SplicerKind::Workspace { path, .. } = prepared_splicer {

crate_universe/src/cli/vendor.rs

@@ -16,7 +16,7 @@ use crate::context::Context;
 use crate::lockfile::{lock_context, write_lockfile};
 use crate::metadata::CargoUpdateRequest;
 use crate::metadata::TreeResolver;
-use crate::metadata::{Annotations, Cargo, Generator, MetadataGenerator, VendorGenerator};
+use crate::metadata::{Annotations, Cargo, VendorGenerator};
 use crate::rendering::{render_module_label, write_outputs, Renderer};
 use crate::splicing::{generate_lockfile, Splicer, SplicingManifest, WorkspaceMetadata};
 use crate::utils::normalize_cargo_file_paths;
@@ -246,10 +246,9 @@ pub fn vendor(opt: VendorOptions) -> anyhow::Result<()> {
     )?;
 
     // Write metadata to the workspace for future reuse
-    let (cargo_metadata, cargo_lockfile) = Generator::new()
-        .with_cargo(cargo.clone())
-        .with_rustc(opt.rustc.clone())
-        .generate(manifest_path.as_path_buf())?;
+    let cargo_metadata = cargo
+        .metadata_command_with_options(manifest_path.as_path_buf().as_ref(), vec!["--locked".to_owned()])?
+        .exec()?;
 
     // Annotate metadata
     let annotations = Annotations::new(

crate_universe/src/metadata.rs

@@ -5,83 +5,19 @@ mod cargo_tree_resolver;
 mod dependency;
 mod metadata_annotation;
 
-use std::env;
 use std::fs;
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
 
 use anyhow::{bail, Context, Result};
 use camino::Utf8Path;
-use cargo_lock::Lockfile as CargoLockfile;
-use cargo_metadata::Metadata as CargoMetadata;
 use tracing::debug;
 
 pub(crate) use self::cargo_bin::*;
 pub(crate) use self::cargo_tree_resolver::*;
 pub(crate) use self::dependency::*;
 pub(crate) use self::metadata_annotation::*;
 
-// TODO: This should also return a set of [crate-index::IndexConfig]s for packages in metadata.packages
-/// A Trait for generating metadata (`cargo metadata` output and a lock file) from a Cargo manifest.
-pub(crate) trait MetadataGenerator {
-    fn generate<T: AsRef<Path>>(&self, manifest_path: T) -> Result<(CargoMetadata, CargoLockfile)>;
-}
-
-/// Generates Cargo metadata and a lockfile from a provided manifest.
-pub(crate) struct Generator {
-    /// The path to a `cargo` binary
-    cargo_bin: Cargo,
-
-    /// The path to a `rustc` binary
-    rustc_bin: PathBuf,
-}
-
-impl Generator {
-    pub(crate) fn new() -> Self {
-        let rustc_bin = PathBuf::from(env::var("RUSTC").unwrap_or_else(|_| "rustc".to_string()));
-        Generator {
-            cargo_bin: Cargo::new(
-                PathBuf::from(env::var("CARGO").unwrap_or_else(|_| "cargo".to_string())),
-                rustc_bin.clone(),
-            ),
-            rustc_bin,
-        }
-    }
-
-    pub(crate) fn with_cargo(mut self, cargo_bin: Cargo) -> Self {
-        self.cargo_bin = cargo_bin;
-        self
-    }
-
-    pub(crate) fn with_rustc(mut self, rustc_bin: PathBuf) -> Self {
-        self.rustc_bin = rustc_bin;
-        self
-    }
-}
-
-impl MetadataGenerator for Generator {
-    fn generate<T: AsRef<Path>>(&self, manifest_path: T) -> Result<(CargoMetadata, CargoLockfile)> {
-        let manifest_dir = manifest_path
-            .as_ref()
-            .parent()
-            .expect("The manifest should have a parent directory");
-        let lockfile = {
-            let lock_path = manifest_dir.join("Cargo.lock");
-            if !lock_path.exists() {
-                bail!("No `Cargo.lock` file was found with the given manifest")
-            }
-            cargo_lock::Lockfile::load(lock_path)?
-        };
-
-        let metadata = self
-            .cargo_bin
-            .metadata_command_with_options(manifest_path.as_ref(), vec!["--locked".to_owned()])?
-            .exec()?;
-
-        Ok((metadata, lockfile))
-    }
-}
-
 /// A configuration describing how to invoke [cargo update](https://doc.rust-lang.org/cargo/commands/cargo-update.html).
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum CargoUpdateRequest {
@@ -340,14 +276,6 @@ impl VendorGenerator {
     }
 }
 
-/// A helper function for writing Cargo metadata to a file.
-pub(crate) fn write_metadata(path: &Path, metadata: &cargo_metadata::Metadata) -> Result<()> {
-    let content =
-        serde_json::to_string_pretty(metadata).context("Failed to serialize Cargo Metadata")?;
-
-    fs::write(path, content).context("Failed to write metadata to disk")
-}
-
 /// A helper function for deserializing Cargo metadata and lockfiles
 pub(crate) fn load_metadata(
     metadata_path: &Path,