Report the CargoWorkspace event

The event contains the names (NB: not the package id's) of packages which were detected in the current cargo workspace.

Possibly must be sent optionally in the future, because we should also support non cargo workspaces.

src/context.rs

@@ -74,6 +74,16 @@ impl Context {
         }
     }
 
+    pub fn environment_context(&self) -> &EnvironmentContext {
+        match self {
+            Context::Find(ctx) => &ctx.environment,
+            Context::List(ctx) => &ctx.environment,
+            Context::Set(ctx) => &ctx.environment,
+            Context::Show(ctx) => &ctx.environment,
+            Context::Verify(ctx) => &ctx.environment,
+        }
+    }
+
     /// Returns the inner find context, if it was present.
     pub fn to_find_context(self) -> Option<FindContext> {
         if let Self::Find(ctx) = self {
@@ -314,15 +324,22 @@ impl EnvironmentContext {
 
 #[derive(Clone, Debug)]
 pub struct WorkspacePackages {
-    _selected: Vec<cargo_metadata::Package>,
+    selected: Vec<cargo_metadata::Package>,
 }
 
 impl WorkspacePackages {
     pub fn from_iter(selected: impl IntoIterator<Item = cargo_metadata::Package>) -> Self {
         Self {
-            _selected: selected.into_iter().collect(),
+            selected: selected.into_iter().collect(),
         }
     }
+
+    pub fn names(&self) -> Vec<String> {
+        self.selected
+            .iter()
+            .map(|pkg| pkg.name.to_string())
+            .collect()
+    }
 }
 
 #[derive(Clone, Copy, Debug, Default, PartialEq, ValueEnum)]

src/lib.rs

@@ -27,7 +27,7 @@ pub use crate::sub_command::{Find, List, Set, Show, SubCommand, Verify};
 use crate::check::RustupToolchainCheck;
 use crate::context::ReleaseSource;
 use crate::error::{CargoMSRVError, TResult};
-use crate::reporter::event::{Meta, SubcommandInit};
+use crate::reporter::event::{CargoWorkspace, Meta, SubcommandInit};
 use crate::reporter::{Event, Reporter};
 use rust_releases::semver;
 
@@ -60,6 +60,9 @@ pub(crate) mod writer;
 
 pub fn run_app(ctx: &Context, reporter: &impl Reporter) -> TResult<()> {
     reporter.report_event(Meta::default())?;
+    reporter.report_event(CargoWorkspace::new(
+        ctx.environment_context().workspace_packages.names(),
+    ))?;
     reporter.report_event(SubcommandInit::new(ctx.reporting_name()))?;
 
     match ctx {

src/reporter/event.rs

@@ -11,6 +11,7 @@ pub use scope::TestScopeGenerator;
 pub use auxiliary_output::{
     AuxiliaryOutput, Destination, Item as AuxiliaryOutputItem, MsrvKind, ToolchainFileKind,
 };
+pub use cargo_workspace::CargoWorkspace;
 pub use check_method::{CheckMethod, Method};
 pub use check_result::CheckResult;
 pub use check_toolchain::CheckToolchain;
@@ -41,6 +42,7 @@ mod types;
 
 // specific events
 mod auxiliary_output;
+mod cargo_workspace;
 mod check_method;
 mod check_result;
 mod check_toolchain;
@@ -123,6 +125,9 @@ pub enum Message {
     // setup
     Meta(Meta),
 
+    // package selection
+    CargoWorkspace(CargoWorkspace),
+
     // get rust-releases index
     FetchIndex(FetchIndex), // todo!
     UnableToConfirmValidReleaseVersion(UnableToConfirmValidReleaseVersion),

src/reporter/event/cargo_workspace.rs

@@ -0,0 +1,19 @@
+use crate::reporter::{Event, Message};
+
+#[derive(Clone, Debug, Eq, PartialEq, serde::Serialize)]
+#[serde(rename_all = "snake_case")]
+pub struct CargoWorkspace {
+    package_names: Vec<String>,
+}
+
+impl CargoWorkspace {
+    pub fn new(package_names: Vec<String>) -> Self {
+        Self { package_names }
+    }
+}
+
+impl From<CargoWorkspace> for Event {
+    fn from(it: CargoWorkspace) -> Self {
+        Message::CargoWorkspace(it).into()
+    }
+}