Merge #3781

3781: Add crate versions when running cargo -p commands. r=matklad a=o0Ignition0o

If someone (unfortunately) creates a project that happens to have the same name as one of its (future) dependencies, there is [a way for them to change the dependency's alias in the Cargo.toml file](https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html#renaming-dependencies-in-cargotoml), to mitigate the name conflict. Unfortunately cargo -p commands don't seem to pick it up, which seems to put rust-analyzer run commands in a tough situation: 

```
> Executing task: cargo test --package config --example default -- tests --nocapture <

error: There are multiple `config` packages in your project, and the specification `config` is ambiguous.
Please re-run this command with `-p <spec>` where `<spec>` is one of the following:
  config:0.1.0
  config:0.9.3
The terminal process terminated with exit code: 101
```

cargo suggests us to be more specific and refer to a package by its name and version, which this PR achieves.

I passed the version as a String because I don't really understand how the ra_db types work, but I would love to switch it to [a fully fledged Version type](https://steveklabnik.github.io/semver/semver/index.html) if you guide me towards that :)



Co-authored-by: o0Ignition0o <jeremy.lempereur@gmail.com>

crates/ra_project_model/src/cargo_workspace.rs

@@ -75,6 +75,7 @@ pub type Target = Idx<TargetData>;
 
 #[derive(Debug, Clone)]
 pub struct PackageData {
+    pub id: String,
     pub name: String,
     pub manifest: PathBuf,
     pub targets: Vec<Target>,
@@ -180,6 +181,7 @@ impl CargoWorkspace {
                 .with_context(|| format!("Failed to parse edition {}", edition))?;
             let pkg = packages.alloc(PackageData {
                 name,
+                id: id.to_string(),
                 manifest: manifest_path,
                 targets: Vec::new(),
                 is_member,
@@ -249,6 +251,18 @@ impl CargoWorkspace {
     pub fn workspace_root(&self) -> &Path {
         &self.workspace_root
     }
+
+    pub fn package_flag(&self, package: &PackageData) -> String {
+        if self.is_unique(&*package.name) {
+            package.name.clone()
+        } else {
+            package.id.clone()
+        }
+    }
+
+    fn is_unique(&self, name: &str) -> bool {
+        self.packages.iter().filter(|(_, v)| v.name == name).count() == 1
+    }
 }
 
 #[derive(Debug, Clone, Default)]

crates/rust-analyzer/src/cargo_target_spec.rs

@@ -77,7 +77,7 @@ impl CargoTargetSpec {
             ProjectWorkspace::Cargo { cargo, .. } => {
                 let tgt = cargo.target_by_root(&path)?;
                 Some(CargoTargetSpec {
-                    package: cargo[cargo[tgt].package].name.clone(),
+                    package: cargo.package_flag(&cargo[cargo[tgt].package]),
                     target: cargo[tgt].name.clone(),
                     target_kind: cargo[tgt].kind,
                 })