Add upgrade subcommand

src/bin/cargo-component.rs

@@ -1,6 +1,6 @@
 use anyhow::{bail, Result};
 use cargo_component::{
-    commands::{AddCommand, KeyCommand, NewCommand, PublishCommand, UpdateCommand},
+    commands::{AddCommand, KeyCommand, NewCommand, PublishCommand, UpdateCommand, UpgradeCommand},
     config::{CargoArguments, Config},
     load_component_metadata, load_metadata, run_cargo_command,
 };
@@ -23,6 +23,7 @@ const BUILTIN_COMMANDS: &[&str] = &[
     "remove",
     "rm",
     "update",
+    "upgrade",
     "vendor",
     "yank",
 ];
@@ -72,6 +73,7 @@ enum Command {
     New(NewCommand),
     // TODO: Remove(RemoveCommand),
     Update(UpdateCommand),
+    Upgrade(UpgradeCommand),
     Publish(PublishCommand),
     // TODO: Yank(YankCommand),
     // TODO: Vendor(VendorCommand),
@@ -115,6 +117,7 @@ async fn main() -> Result<()> {
                     Command::Key(cmd) => cmd.exec().await,
                     Command::New(cmd) => cmd.exec().await,
                     Command::Update(cmd) => cmd.exec().await,
+                    Command::Upgrade(cmd) => cmd.exec().await,
                     Command::Publish(cmd) => cmd.exec().await,
                 },
             } {
@@ -159,7 +162,11 @@ async fn main() -> Result<()> {
                 cargo_args.color.unwrap_or_default(),
             ))?;
 
-            let metadata = load_metadata(config.terminal(), cargo_args.manifest_path.as_deref())?;
+            let metadata = load_metadata(
+                config.terminal(),
+                cargo_args.manifest_path.as_deref(),
+                false,
+            )?;
             let packages = load_component_metadata(
                 &metadata,
                 cargo_args.packages.iter(),

src/commands.rs

@@ -5,9 +5,11 @@ mod key;
 mod new;
 mod publish;
 mod update;
+mod upgrade;
 
 pub use self::add::*;
 pub use self::key::*;
 pub use self::new::*;
 pub use self::publish::*;
 pub use self::update::*;
+pub use self::upgrade::*;

src/commands/add.rs

@@ -65,7 +65,7 @@ impl AddCommand {
     /// Executes the command
     pub async fn exec(self) -> Result<()> {
         let config = Config::new(self.common.new_terminal())?;
-        let metadata = load_metadata(config.terminal(), self.manifest_path.as_deref())?;
+        let metadata = load_metadata(config.terminal(), self.manifest_path.as_deref(), false)?;
 
         let PackageComponentMetadata { package, metadata }: PackageComponentMetadata<'_> =
             match &self.spec {

src/commands/publish.rs

@@ -92,7 +92,7 @@ impl PublishCommand {
             }
         }
 
-        let metadata = load_metadata(config.terminal(), self.manifest_path.as_deref())?;
+        let metadata = load_metadata(config.terminal(), self.manifest_path.as_deref(), false)?;
         let packages = [PackageComponentMetadata::new(
             if let Some(spec) = &self.cargo_package {
                 metadata

src/commands/update.rs

@@ -38,7 +38,7 @@ impl UpdateCommand {
     pub async fn exec(self) -> Result<()> {
         log::debug!("executing update command");
         let config = Config::new(self.common.new_terminal())?;
-        let metadata = load_metadata(config.terminal(), self.manifest_path.as_deref())?;
+        let metadata = load_metadata(config.terminal(), self.manifest_path.as_deref(), false)?;
         let packages = load_component_metadata(&metadata, [].iter(), true)?;
 
         let network_allowed = !self.frozen && !self.offline;

src/commands/upgrade.rs

@@ -0,0 +1,196 @@
+use crate::{load_metadata, Config, BINDINGS_CRATE_NAME};
+use anyhow::{Context, Result};
+use cargo_component_core::command::CommonOptions;
+use cargo_metadata::Metadata;
+use clap::Args;
+use std::{fs, path::PathBuf};
+use toml_edit::{value, Document};
+
+/// Install the latest version of cargo-component and upgrade to the
+/// corresponding version of cargo-component-bindings.
+#[derive(Args)]
+#[clap(disable_version_flag = true)]
+pub struct UpgradeCommand {
+    /// The common command options
+    #[clap(flatten)]
+    pub common: CommonOptions,
+
+    /// Don't actually write the Cargo.toml changes.
+    ///
+    /// Note that this will not prevent installing a new version of cargo-component itself;
+    /// if you want to do that, you must also specify the '--no-install' flag.
+    #[clap(long = "dry-run")]
+    pub dry_run: bool,
+
+    /// Path to Cargo.toml
+    #[clap(long = "manifest-path", value_name = "PATH")]
+    pub manifest_path: Option<PathBuf>,
+
+    /// Skip installing the latest version of cargo-component;
+    /// instead just upgrade cargo-component-bindings to match
+    /// the version currently running.
+    #[clap(long = "no-install")]
+    pub no_install: bool,
+}
+
+impl UpgradeCommand {
+    /// Executes the command.
+    pub async fn exec(self) -> Result<()> {
+        log::debug!("executing upgrade command");
+
+        if !self.no_install {
+            // Do the self-upgrade first, and then _unconditionally_ delegate
+            // to whatever version of `cargo-component` is now at the same path as the
+            // current executable.
+            //
+            // This avoids needing to query crates.io ourselves, scrape the version
+            // from `cargo-component --version` etc.
+            //
+            // (We can't tell whether or not cargo-install actually installed anything
+            // without scraping its output; it considers "already installed" as success.)
+            //
+            // Skip this in tests, but still delegate to a new instance of `cargo-component`
+            // so that we can exercise as much of the flow as practicable.
+            #[cfg(not(test))]
+            upgrade_self()?;
+            run_cargo_component_and_exit();
+        }
+
+        let config = Config::new(self.common.new_terminal())?;
+        let metadata = load_metadata(config.terminal(), self.manifest_path.as_deref(), true)?;
+
+        upgrade_bindings(&config, &metadata, self.dry_run).await?;
+
+        Ok(())
+    }
+}
+
+#[cfg(not(test))]
+fn upgrade_self() -> Result<()> {
+    log::debug!("running self-upgrade using cargo-install");
+
+    let mut command = std::process::Command::new("cargo");
+    command.args(["install", "cargo-component"]);
+
+    match command.status() {
+        Ok(status) => {
+            if !status.success() {
+                std::process::exit(status.code().unwrap_or(1));
+            }
+            Ok(())
+        }
+        Err(e) => {
+            anyhow::bail!("failed to execute `cargo install` command: {e}")
+        }
+    }
+}
+
+fn run_cargo_component_and_exit() -> ! {
+    log::debug!("running cargo-component from same path as this process");
+
+    let mut args = std::env::args();
+
+    // argv[0] cannot be relied up on as a path to the executable;
+    // skip it and use `current_exe` instead.
+    let _ = args.next();
+
+    let mut command = std::process::Command::new(
+        std::env::current_exe().expect("Failed to get path to current executable"),
+    );
+    command.args(args);
+
+    // Unconditionally specify '--no-install' to prevent infinite recursion.
+    command.arg("--no-install");
+
+    match command.status() {
+        Ok(status) => {
+            std::process::exit(status.code().unwrap_or(1));
+        }
+        Err(e) => {
+            log::error!("failed to delegate to `cargo-component` command: {e}");
+            std::process::exit(1);
+        }
+    }
+}
+
+async fn upgrade_bindings(config: &Config, metadata: &Metadata, dry_run: bool) -> Result<()> {
+    let self_version = semver::VersionReq::parse(env!("CARGO_PKG_VERSION"))
+        .context("Failed to parse current cargo-component version")?;
+
+    for package in metadata.workspace_packages() {
+        let Some(bindings_dep) = package
+            .dependencies
+            .iter()
+            .find(|dep| dep.name == "cargo-component-bindings")
+        else {
+            log::debug!(
+                "Workspace package {} doesn't depend on cargo-component-bindings",
+                package.name
+            );
+            continue;
+        };
+
+        if bindings_dep.req == self_version {
+            config.terminal().status(
+                "Skipping",
+                format!(
+                    "package `{}` as it already uses the current bindings crate version",
+                    package.name
+                ),
+            )?;
+            continue;
+        }
+
+        let manifest_path = package.manifest_path.as_std_path();
+        let manifest = fs::read_to_string(manifest_path).with_context(|| {
+            format!(
+                "failed to read manifest file `{path}`",
+                path = manifest_path.display()
+            )
+        })?;
+
+        let mut doc: Document = manifest.parse().with_context(|| {
+            format!(
+                "failed to parse manifest file `{path}`",
+                path = manifest_path.display()
+            )
+        })?;
+
+        doc["dependencies"][BINDINGS_CRATE_NAME] = value(env!("CARGO_PKG_VERSION"));
+
+        // Do this fairly late, so we exercise as much of the real code as possible
+        // (encounter explosions that would happen if doing it for real)
+        // without actually writing back the file.
+        if dry_run {
+            config.terminal().status(
+                "Would update",
+                format!(
+                    "{path} from {from} to {to}",
+                    path = manifest_path.display(),
+                    from = bindings_dep.req,
+                    to = env!("CARGO_PKG_VERSION")
+                ),
+            )?;
+            continue;
+        }
+
+        fs::write(manifest_path, doc.to_string()).with_context(|| {
+            format!(
+                "failed to write manifest file `{path}`",
+                path = manifest_path.display()
+            )
+        })?;
+
+        config.terminal().status(
+            "Updated",
+            format!(
+                "{path} from {from} to {to}",
+                path = manifest_path.display(),
+                from = bindings_dep.req,
+                to = env!("CARGO_PKG_VERSION")
+            ),
+        )?;
+    }
+
+    Ok(())
+}

src/lib.rs

@@ -200,7 +200,11 @@ fn last_modified_time(path: &Path) -> Result<SystemTime> {
 }
 
 /// Loads the workspace metadata based on the given manifest path.
-pub fn load_metadata(terminal: &Terminal, manifest_path: Option<&Path>) -> Result<Metadata> {
+pub fn load_metadata(
+    terminal: &Terminal,
+    manifest_path: Option<&Path>,
+    ignore_version_mismatch: bool,
+) -> Result<Metadata> {
     let mut command = MetadataCommand::new();
     command.no_deps();
 
@@ -222,9 +226,10 @@ pub fn load_metadata(terminal: &Terminal, manifest_path: Option<&Path>) -> Resul
                 continue;
             }
 
-            if dep
-                .req
-                .matches(&Version::parse(env!("CARGO_PKG_VERSION")).unwrap())
+            if ignore_version_mismatch
+                || dep
+                    .req
+                    .matches(&Version::parse(env!("CARGO_PKG_VERSION")).unwrap())
             {
                 continue;
             }

tests/support/mod.rs

@@ -319,10 +319,16 @@ impl Project {
         Ok(self)
     }
 
+    pub fn read_manifest(&self) -> Result<Document> {
+        let manifest_path = self.root.join("Cargo.toml");
+        let manifest_text = fs::read_to_string(manifest_path)?;
+        Ok(manifest_text.parse()?)
+    }
+
     pub fn update_manifest(&self, f: impl FnOnce(Document) -> Result<Document>) -> Result<()> {
+        let manifest = self.read_manifest()?;
         let manifest_path = self.root.join("Cargo.toml");
-        let manifest = fs::read_to_string(&manifest_path)?;
-        fs::write(manifest_path, f(manifest.parse()?)?.to_string())?;
+        fs::write(manifest_path, f(manifest)?.to_string())?;
         Ok(())
     }