Track editable requirements in lockfile (#3725)

## Summary

This PR adds editables using a new source type (`editable+...`), and
then extracts the editables from the lockfile in `uv sync`.

Closes https://github.com/astral-sh/uv/issues/3695.

crates/distribution-types/src/resolution.rs

@@ -1,8 +1,12 @@
 use rustc_hash::FxHashMap;
 
+use pep508_rs::VerbatimUrl;
 use uv_normalize::PackageName;
 
-use crate::{BuiltDist, Dist, Name, Requirement, RequirementSource, ResolvedDist, SourceDist};
+use crate::{
+    BuiltDist, DirectorySourceDist, Dist, InstalledDirectUrlDist, InstalledDist, LocalEditable,
+    Name, Requirement, RequirementSource, ResolvedDist, SourceDist,
+};
 
 /// A set of packages pinned at specific versions.
 #[derive(Debug, Default, Clone)]
@@ -68,6 +72,35 @@ impl Resolution {
         requirements.sort_unstable_by(|a, b| a.name.cmp(&b.name));
         requirements
     }
+
+    /// Return an iterator over the [`LocalEditable`] entities in this resolution.
+    pub fn editables(&self) -> impl Iterator<Item = LocalEditable> + '_ {
+        self.0.values().filter_map(|dist| match dist {
+            ResolvedDist::Installable(Dist::Source(SourceDist::Directory(
+                DirectorySourceDist {
+                    path,
+                    url,
+                    editable: true,
+                    ..
+                },
+            ))) => Some(LocalEditable {
+                url: url.clone(),
+                path: path.clone(),
+                extras: vec![],
+            }),
+            ResolvedDist::Installed(InstalledDist::Url(InstalledDirectUrlDist {
+                path,
+                url,
+                editable: true,
+                ..
+            })) => Some(LocalEditable {
+                url: VerbatimUrl::from_url(url.clone()),
+                path: path.clone(),
+                extras: vec![],
+            }),
+            _ => None,
+        })
+    }
 }
 
 impl From<&ResolvedDist> for Requirement {

crates/uv-configuration/src/package_options.rs

@@ -3,9 +3,10 @@ use pep508_rs::PackageName;
 use rustc_hash::FxHashSet;
 
 /// Whether to reinstall packages.
-#[derive(Debug, Clone)]
+#[derive(Debug, Default, Clone)]
 pub enum Reinstall {
     /// Don't reinstall any packages; respect the existing installation.
+    #[default]
     None,
 
     /// Reinstall all packages in the plan.

crates/uv-resolver/src/lock.rs

@@ -277,6 +277,9 @@ impl Distribution {
                 SourceKind::Directory => {
                     unreachable!("Wheels cannot come from directory sources")
                 }
+                SourceKind::Editable => {
+                    unreachable!("Wheels cannot come from editable sources")
+                }
             };
         }
 
@@ -301,6 +304,16 @@ impl Distribution {
                     let source_dist = distribution_types::SourceDist::Directory(dir_dist);
                     Dist::Source(source_dist)
                 }
+                SourceKind::Editable => {
+                    let dir_dist = DirectorySourceDist {
+                        name: self.id.name.clone(),
+                        url: VerbatimUrl::from_url(self.id.source.url.clone()),
+                        path: self.id.source.url.to_file_path().unwrap(),
+                        editable: true,
+                    };
+                    let source_dist = distribution_types::SourceDist::Directory(dir_dist);
+                    Dist::Source(source_dist)
+                }
                 SourceKind::Git(git) => {
                     // Reconstruct the `GitUrl` from the `GitSource`.
                     let git_url = uv_git::GitUrl::new(
@@ -513,7 +526,11 @@ impl Source {
 
     fn from_directory_source_dist(directory_dist: &DirectorySourceDist) -> Source {
         Source {
-            kind: SourceKind::Directory,
+            kind: if directory_dist.editable {
+                SourceKind::Editable
+            } else {
+                SourceKind::Directory
+            },
             url: directory_dist.url.to_url(),
         }
     }
@@ -583,6 +600,10 @@ impl std::str::FromStr for Source {
                 kind: SourceKind::Directory,
                 url,
             }),
+            "editable" => Ok(Source {
+                kind: SourceKind::Editable,
+                url,
+            }),
             name => Err(SourceParseError::unrecognized_source_name(s, name)),
         }
     }
@@ -624,6 +645,7 @@ pub(crate) enum SourceKind {
     Direct(DirectSource),
     Path,
     Directory,
+    Editable,
 }
 
 impl SourceKind {
@@ -634,6 +656,7 @@ impl SourceKind {
             SourceKind::Direct(_) => "direct",
             SourceKind::Path => "path",
             SourceKind::Directory => "directory",
+            SourceKind::Editable => "editable",
         }
     }
 
@@ -644,7 +667,7 @@ impl SourceKind {
     fn requires_hash(&self) -> bool {
         match *self {
             SourceKind::Registry | SourceKind::Direct(_) | SourceKind::Path => true,
-            SourceKind::Git(_) | SourceKind::Directory => false,
+            SourceKind::Git(_) | SourceKind::Directory | SourceKind::Editable => false,
         }
     }
 }

crates/uv/src/commands/project/sync.rs

@@ -5,7 +5,7 @@ use install_wheel_rs::linker::LinkMode;
 use uv_cache::Cache;
 use uv_client::RegistryClientBuilder;
 use uv_configuration::{
-    Concurrency, ConfigSettings, NoBinary, NoBuild, PreviewMode, SetupPyStrategy,
+    Concurrency, ConfigSettings, NoBinary, NoBuild, PreviewMode, Reinstall, SetupPyStrategy,
 };
 use uv_dispatch::BuildDispatch;
 use uv_installer::SitePackages;
@@ -65,6 +65,7 @@ pub(crate) async fn sync(
     let no_build = NoBuild::default();
     let setup_py = SetupPyStrategy::default();
     let concurrency = Concurrency::default();
+    let reinstall = Reinstall::default();
 
     // Create a build dispatch.
     let build_dispatch = BuildDispatch::new(
@@ -84,8 +85,23 @@ pub(crate) async fn sync(
         concurrency,
     );
 
-    // TODO(konsti): Read editables from lockfile.
-    let editables = ResolvedEditables::default();
+    let site_packages = SitePackages::from_executable(&venv)?;
+
+    // Build any editables.
+    let editables = ResolvedEditables::resolve(
+        resolution.editables(),
+        &site_packages,
+        &reinstall,
+        &hasher,
+        venv.interpreter(),
+        tags,
+        cache,
+        &client,
+        &build_dispatch,
+        concurrency,
+        printer,
+    )
+    .await?;
 
     let site_packages = SitePackages::from_executable(&venv)?;