Editable project location and Required-by for pip show (#2589)

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## Summary

<!-- What's the purpose of the change? What does it do, and why? -->

- Displays missing packages as single-line warnings.
- Adds support for `Editable project location` and `Required-by` fields
in `pip show`.

Part of #2526.

# Conflicts:
#	crates/uv-dispatch/src/lib.rs
#	crates/uv-resolver/src/resolver/mod.rs
#	crates/uv-resolver/tests/resolver.rs
#	crates/uv-traits/src/lib.rs
#	crates/uv/src/commands/pip_compile.rs

# Conflicts:
#	crates/uv/src/commands/pip_sync.rs

crates/uv-dev/src/resolve_cli.rs

@@ -14,7 +14,7 @@ use pep508_rs::Requirement;
 use uv_cache::{Cache, CacheArgs};
 use uv_client::{FlatIndex, FlatIndexClient, RegistryClientBuilder};
 use uv_dispatch::BuildDispatch;
-use uv_installer::NoBinary;
+use uv_installer::{NoBinary, SitePackages};
 use uv_interpreter::PythonEnvironment;
 use uv_resolver::{InMemoryIndex, Manifest, Options, Resolver};
 use uv_types::{BuildIsolation, ConfigSettings, InFlight, NoBuild, SetupPyStrategy};
@@ -88,6 +88,8 @@ pub(crate) async fn resolve_cli(args: ResolveCliArgs) -> Result<()> {
         &NoBinary::None,
     );
 
+    let site_packages = SitePackages::from_executable(&venv)?;
+
     // Copied from `BuildDispatch`
     let tags = venv.interpreter().tags()?;
     let resolver = Resolver::new(
@@ -100,6 +102,7 @@ pub(crate) async fn resolve_cli(args: ResolveCliArgs) -> Result<()> {
         &flat_index,
         &index,
         &build_dispatch,
+        &site_packages,
     )?;
     let resolution_graph = resolver.resolve().await.with_context(|| {
         format!(

crates/uv-dispatch/src/lib.rs

@@ -21,7 +21,7 @@ use uv_installer::{Downloader, Installer, NoBinary, Plan, Planner, Reinstall, Si
 use uv_interpreter::{Interpreter, PythonEnvironment};
 use uv_resolver::{InMemoryIndex, Manifest, Options, Resolver};
 use uv_types::{
-    BuildContext, BuildIsolation, BuildKind, ConfigSettings, InFlight, NoBuild, SetupPyStrategy,
+    BuildContext, BuildIsolation, BuildKind, ConfigSettings, InFlight, NoBuild, EmptyInstalledPackages, SetupPyStrategy,
 };
 
 /// The main implementation of [`BuildContext`], used by the CLI, see [`BuildContext`]
@@ -145,6 +145,7 @@ impl<'a> BuildContext for BuildDispatch<'a> {
             self.flat_index,
             self.index,
             self,
+            &EmptyInstalledPackages,
         )?;
         let graph = resolver.resolve().await.with_context(|| {
             format!(

crates/uv-installer/src/site_packages.rs

@@ -14,6 +14,7 @@ use requirements_txt::EditableRequirement;
 use uv_cache::{ArchiveTarget, ArchiveTimestamp};
 use uv_interpreter::PythonEnvironment;
 use uv_normalize::PackageName;
+use uv_traits::InstalledPackagesProvider;
 
 use crate::is_dynamic;
 
@@ -577,3 +578,23 @@ impl Diagnostic {
         }
     }
 }
+
+impl InstalledPackagesProvider for SitePackages<'_> {
+    fn iter(&self) -> impl Iterator<Item = &InstalledDist> {
+        self.iter()
+    }
+
+    fn get_packages(&self, name: &PackageName) -> Vec<&InstalledDist> {
+        self.get_packages(name)
+    }
+}
+
+impl InstalledPackagesProvider for &SitePackages<'_> {
+    fn iter(&self) -> impl Iterator<Item = &InstalledDist> {
+        (*self).iter()
+    }
+
+    fn get_packages(&self, name: &PackageName) -> Vec<&InstalledDist> {
+        (*self).get_packages(name)
+    }
+}

crates/uv-resolver/src/resolver/mod.rs

@@ -31,7 +31,7 @@ use uv_client::{FlatIndex, RegistryClient};
 use uv_distribution::DistributionDatabase;
 use uv_interpreter::Interpreter;
 use uv_normalize::PackageName;
-use uv_types::BuildContext;
+use uv_types::{BuildContext, InstalledPackagesProvider};
 
 use crate::candidate_selector::{CandidateDist, CandidateSelector};
 use crate::constraints::Constraints;
@@ -89,7 +89,11 @@ enum ResolverVersion {
     Unavailable(Version, UnavailableVersion),
 }
 
-pub struct Resolver<'a, Provider: ResolverProvider> {
+pub struct Resolver<
+    'a,
+    Provider: ResolverProvider,
+    InstalledPackages: InstalledPackagesProvider + Send + Sync,
+> {
     project: Option<PackageName>,
     requirements: Vec<Requirement>,
     constraints: Constraints,
@@ -103,6 +107,7 @@ pub struct Resolver<'a, Provider: ResolverProvider> {
     python_requirement: PythonRequirement,
     selector: CandidateSelector,
     index: &'a InMemoryIndex,
+    installed_packages: &'a InstalledPackages,
     /// Incompatibilities for packages that are entirely unavailable
     unavailable_packages: DashMap<PackageName, UnavailablePackage>,
     /// The set of all registry-based packages visited during resolution.
@@ -111,7 +116,12 @@ pub struct Resolver<'a, Provider: ResolverProvider> {
     provider: Provider,
 }
 
-impl<'a, Context: BuildContext + Send + Sync> Resolver<'a, DefaultResolverProvider<'a, Context>> {
+impl<
+        'a,
+        Context: BuildContext + Send + Sync,
+        InstalledPackages: InstalledPackagesProvider + Send + Sync,
+    > Resolver<'a, DefaultResolverProvider<'a, Context>, InstalledPackages>
+{
     /// Initialize a new resolver using the default backend doing real requests.
     ///
     /// Reads the flat index entries.
@@ -126,6 +136,7 @@ impl<'a, Context: BuildContext + Send + Sync> Resolver<'a, DefaultResolverProvid
         flat_index: &'a FlatIndex,
         index: &'a InMemoryIndex,
         build_context: &'a Context,
+        installed_packages: &'a InstalledPackages,
     ) -> Result<Self, ResolveError> {
         let provider = DefaultResolverProvider::new(
             client,
@@ -145,11 +156,17 @@ impl<'a, Context: BuildContext + Send + Sync> Resolver<'a, DefaultResolverProvid
             PythonRequirement::new(interpreter, markers),
             index,
             provider,
+            installed_packages,
         )
     }
 }
 
-impl<'a, Provider: ResolverProvider> Resolver<'a, Provider> {
+impl<
+        'a,
+        Provider: ResolverProvider,
+        InstalledPackages: InstalledPackagesProvider + Send + Sync,
+    > Resolver<'a, Provider, InstalledPackages>
+{
     /// Initialize a new resolver using a user provided backend.
     pub fn new_custom_io(
         manifest: Manifest,
@@ -158,6 +175,7 @@ impl<'a, Provider: ResolverProvider> Resolver<'a, Provider> {
         python_requirement: PythonRequirement,
         index: &'a InMemoryIndex,
         provider: Provider,
+        installed_packages: &'a InstalledPackages,
     ) -> Result<Self, ResolveError> {
         Ok(Self {
             index,
@@ -177,6 +195,7 @@ impl<'a, Provider: ResolverProvider> Resolver<'a, Provider> {
             python_requirement,
             reporter: None,
             provider,
+            installed_packages,
         })
     }
 

crates/uv-resolver/tests/resolver.rs

@@ -21,7 +21,7 @@ use uv_resolver::{
     Preference, ResolutionGraph, ResolutionMode, Resolver,
 };
 use uv_types::{
-    BuildContext, BuildIsolation, BuildKind, NoBinary, NoBuild, SetupPyStrategy, SourceBuildTrait,
+    BuildContext, BuildIsolation, BuildKind, NoBinary, EmptyInstalledPackages, NoBuild, SetupPyStrategy, SourceBuildTrait,
 };
 
 // Exclude any packages uploaded after this date.
@@ -124,6 +124,7 @@ async fn resolve(
         find_default_python(&Cache::temp().unwrap()).expect("Expected a python to be installed");
     let interpreter = Interpreter::artificial(real_interpreter.platform().clone(), markers.clone());
     let build_context = DummyContext::new(Cache::temp()?, interpreter.clone());
+    let installed_packages = EmptyInstalledPackages;
     let resolver = Resolver::new(
         manifest,
         options,
@@ -134,6 +135,7 @@ async fn resolve(
         &flat_index,
         &index,
         &build_context,
+        &installed_packages,
     )?;
     Ok(resolver.resolve().await?)
 }

crates/uv-types/src/traits.rs

@@ -127,3 +127,25 @@ pub trait SourceBuildTrait {
     fn wheel<'a>(&'a self, wheel_dir: &'a Path)
         -> impl Future<Output = Result<String>> + Send + 'a;
 }
+
+/// A wrapper for [`uv_installer::SitePackages`]
+pub trait InstalledPackagesProvider {
+    fn iter(&self) -> impl Iterator<Item = &InstalledDist>;
+    fn get_packages(&self, name: &PackageName) -> Vec<&InstalledDist>;
+}
+
+/// An [`InstalledPackagesProvider`] with no packages in it.
+pub struct EmptyInstalledPackages;
+
+impl InstalledPackagesProvider for EmptyInstalledPackages {
+    fn get_packages(
+        &self,
+        _name: &pep508_rs::PackageName,
+    ) -> Vec<&distribution_types::InstalledDist> {
+        Vec::new()
+    }
+
+    fn iter(&self) -> impl Iterator<Item = &distribution_types::InstalledDist> {
+        std::iter::empty()
+    }
+}

crates/uv/src/commands/pip_compile.rs

@@ -35,7 +35,7 @@ use uv_resolver::{
     AnnotationStyle, DependencyMode, DisplayResolutionGraph, InMemoryIndex, Manifest,
     OptionsBuilder, PreReleaseMode, PythonRequirement, ResolutionMode, Resolver,
 };
-use uv_types::{BuildIsolation, ConfigSettings, InFlight, NoBuild, SetupPyStrategy, Upgrade};
+use uv_types::{BuildIsolation, ConfigSettings, InFlight, EmptyInstalledPackages, NoBuild, SetupPyStrategy, Upgrade};
 use uv_warnings::warn_user;
 
 use crate::commands::reporters::{DownloadReporter, ResolverReporter};
@@ -358,6 +358,7 @@ pub(crate) async fn pip_compile(
         &flat_index,
         &top_level_index,
         &build_dispatch,
+        &EmptyInstalledPackages,
     )?
     .with_reporter(ResolverReporter::from(printer));
 

crates/uv/src/commands/pip_install.rs

@@ -568,6 +568,7 @@ async fn resolve(
         flat_index,
         index,
         build_dispatch,
+        &site_packages,
     )?
     .with_reporter(ResolverReporter::from(printer));
     let resolution = resolver.resolve().await?;

crates/uv/src/commands/pip_sync.rs

@@ -171,6 +171,9 @@ pub(crate) async fn pip_sync(
     let no_binary = no_binary.combine(specified_no_binary);
     let no_build = no_build.combine(specified_no_build);
 
+    // Determine the set of installed packages.
+    let site_packages = SitePackages::from_executable(&venv)?;
+
     // Prep the build context.
     let build_dispatch = BuildDispatch::new(
         &client,
@@ -208,9 +211,6 @@ pub(crate) async fn pip_sync(
         requirements
     };
 
-    // Determine the set of installed packages.
-    let site_packages = SitePackages::from_executable(&venv)?;
-
     // Resolve any editables.
     let resolved_editables = resolve_editables(
         editables,