Use separate rules

crates/uv-dispatch/src/lib.rs

@@ -28,7 +28,7 @@ use uv_distribution_types::{
     PackageConfigSettings, Requirement, Resolution, SourceDist, VersionOrUrlRef,
 };
 use uv_git::GitResolver;
-use uv_installer::{Installer, Plan, Planner, Preparer, SitePackages};
+use uv_installer::{Installer, Plan, Planner, Preparer, SitePackages, SyncModel};
 use uv_pypi_types::Conflicts;
 use uv_python::{Interpreter, PythonEnvironment};
 use uv_resolver::{
@@ -319,6 +319,7 @@ impl BuildContext for BuildDispatch<'_> {
             self.build_options,
             self.hasher,
             self.index_locations,
+            SyncModel::Stateless,
             self.config_settings,
             self.config_settings_package,
             self.extra_build_requires(),

crates/uv-installer/src/lib.rs

@@ -2,7 +2,7 @@ pub use compile::{CompileError, compile_tree};
 pub use installer::{Installer, Reporter as InstallReporter};
 pub use plan::{Plan, Planner};
 pub use preparer::{Error as PrepareError, Preparer, Reporter as PrepareReporter};
-pub use site_packages::{SatisfiesResult, SitePackages, SitePackagesDiagnostic};
+pub use site_packages::{SatisfiesResult, SitePackages, SitePackagesDiagnostic, SyncModel};
 pub use uninstall::{UninstallError, uninstall};
 
 mod compile;

crates/uv-installer/src/plan.rs

@@ -25,6 +25,7 @@ use uv_types::HashStrategy;
 
 use crate::SitePackages;
 use crate::satisfies::RequirementSatisfaction;
+use crate::site_packages::SyncModel;
 
 /// A planner to generate an [`Plan`] based on a set of requirements.
 #[derive(Debug)]
@@ -56,6 +57,7 @@ impl<'a> Planner<'a> {
         build_options: &BuildOptions,
         hasher: &HashStrategy,
         index_locations: &IndexLocations,
+        model: SyncModel,
         config_settings: &ConfigSettings,
         config_settings_package: &PackageConfigSettings,
         extra_build_requires: &ExtraBuildRequires,
@@ -125,6 +127,7 @@ impl<'a> Planner<'a> {
                             dist.name(),
                             installed,
                             &source,
+                            model,
                             config_settings,
                             config_settings_package,
                             extra_build_requires,

crates/uv-installer/src/satisfies.rs

@@ -5,6 +5,7 @@ use same_file::is_same_file;
 use tracing::{debug, trace};
 use url::Url;
 
+use crate::site_packages::SyncModel;
 use uv_cache_info::CacheInfo;
 use uv_cache_key::{CanonicalUrl, RepositoryUrl};
 use uv_distribution_types::{
@@ -32,6 +33,7 @@ impl RequirementSatisfaction {
         name: &PackageName,
         distribution: &InstalledDist,
         source: &RequirementSource,
+        model: SyncModel,
         config_settings: &ConfigSettings,
         config_settings_package: &PackageConfigSettings,
         extra_build_requires: &ExtraBuildRequires,
@@ -55,6 +57,7 @@ impl RequirementSatisfaction {
             );
             dist_build_info != &build_info
         }) {
+            // If the requirement came from a registry,
             debug!("Build info mismatch for {name}: {distribution:?}");
             return Self::OutOfDate;
         }
@@ -63,6 +66,25 @@ impl RequirementSatisfaction {
         match source {
             // If the requirement comes from a registry, check by name.
             RequirementSource::Registry { specifier, .. } => {
+                // If the installed distribution is _not_ from a registry, reject it if and only if
+                // we're in a stateless install.
+                //
+                // For example: the `uv pip` CLI is stateful, in that it "respects"
+                // already-installed packages in the virtual environment. So if you run `uv pip
+                // install ./path/to/idna`, and then `uv pip install anyio` (which depends on
+                // `idna`), we'll "accept" the already-installed `idna` even though it is implicitly
+                // being "required" as a registry package.
+                //
+                // The `uv sync` CLI is stateless, in that all requirements must be defined
+                // declaratively ahead-of-time. So if you `uv sync` to install `./path/to/idna` and
+                // later `uv sync` to install `anyio`, we'll know (during that second sync) if the
+                // already-installed `idna` should come from the registry or not.
+                if model == SyncModel::Stateless {
+                    if !matches!(distribution, InstalledDist::Registry { .. }) {
+                        debug!("Distribution type mismatch for {name}: {distribution:?}");
+                        return Self::Mismatch;
+                    }
+                }
                 if specifier.contains(distribution.version()) {
                     return Self::Satisfied;
                 }

crates/uv-installer/src/site_packages.rs

@@ -296,6 +296,7 @@ impl SitePackages {
         constraints: &[NameRequirementSpecification],
         overrides: &[UnresolvedRequirementSpecification],
         markers: &ResolverMarkerEnvironment,
+        model: SyncModel,
         config_settings: &ConfigSettings,
         config_settings_package: &PackageConfigSettings,
         extra_build_requires: &ExtraBuildRequires,
@@ -385,6 +386,7 @@ impl SitePackages {
             constraints.iter().map(|constraint| &constraint.requirement),
             overrides.iter().map(Cow::as_ref),
             markers,
+            model,
             config_settings,
             config_settings_package,
             extra_build_requires,
@@ -399,6 +401,7 @@ impl SitePackages {
         constraints: impl Iterator<Item = &'a Requirement>,
         overrides: impl Iterator<Item = &'a Requirement>,
         markers: &ResolverMarkerEnvironment,
+        model: SyncModel,
         config_settings: &ConfigSettings,
         config_settings_package: &PackageConfigSettings,
         extra_build_requires: &ExtraBuildRequires,
@@ -460,6 +463,7 @@ impl SitePackages {
                             name,
                             distribution,
                             &requirement.source,
+                            model,
                             config_settings,
                             config_settings_package,
                             extra_build_requires,
@@ -481,6 +485,7 @@ impl SitePackages {
                                 name,
                                 distribution,
                                 &constraint.source,
+                                model,
                                 config_settings,
                                 config_settings_package,
                                 extra_build_requires,
@@ -536,6 +541,19 @@ impl SitePackages {
     }
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum SyncModel {
+    /// A stateful sync, as in the `uv pip` CLI, whereby packages that are already installed in
+    /// the environment may be reused if they implicitly match the requirements. For example, if
+    /// the user installs `./path/to/idna`, then runs `uv pip install anyio` (which depends on
+    /// `idna`), the existing `idna` installation will be reused if it satisfies the requirements,
+    /// even though it is implicitly being requested from the registry.
+    Stateful,
+    /// A stateless sync, as in the `uv sync` CLI, whereby the sources of all packages are defined
+    /// declaratively upfront.
+    Stateless,
+}
+
 /// We check if all requirements are already satisfied, recursing through the requirements tree.
 #[derive(Debug)]
 pub enum SatisfiesResult {

crates/uv/src/commands/pip/install.rs

@@ -22,7 +22,7 @@ use uv_distribution_types::{
 };
 use uv_fs::Simplified;
 use uv_install_wheel::LinkMode;
-use uv_installer::{SatisfiesResult, SitePackages};
+use uv_installer::{SatisfiesResult, SitePackages, SyncModel};
 use uv_normalize::{DefaultExtras, DefaultGroups};
 use uv_pypi_types::Conflicts;
 use uv_python::{
@@ -290,6 +290,7 @@ pub(crate) async fn pip_install(
             &constraints,
             &overrides,
             &marker_env,
+            SyncModel::Stateful,
             config_settings,
             config_settings_package,
             &extra_build_requires,
@@ -601,6 +602,7 @@ pub(crate) async fn pip_install(
     match operations::install(
         &resolution,
         site_packages,
+        SyncModel::Stateful,
         modifications,
         &reinstall,
         &build_options,

crates/uv/src/commands/pip/operations.rs

@@ -25,7 +25,7 @@ use uv_distribution_types::{
 use uv_distribution_types::{DistributionMetadata, InstalledMetadata, Name, Resolution};
 use uv_fs::Simplified;
 use uv_install_wheel::LinkMode;
-use uv_installer::{Plan, Planner, Preparer, SitePackages};
+use uv_installer::{Plan, Planner, Preparer, SitePackages, SyncModel};
 use uv_normalize::PackageName;
 use uv_pep508::{MarkerEnvironment, RequirementOrigin};
 use uv_platform_tags::Tags;
@@ -433,6 +433,7 @@ impl Changelog {
 pub(crate) async fn install(
     resolution: &Resolution,
     site_packages: SitePackages,
+    model: SyncModel,
     modifications: Modifications,
     reinstall: &Reinstall,
     build_options: &BuildOptions,
@@ -463,6 +464,7 @@ pub(crate) async fn install(
             build_options,
             hasher,
             build_dispatch.locations(),
+            model,
             build_dispatch.config_settings(),
             build_dispatch.config_settings_package(),
             build_dispatch.extra_build_requires(),

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

@@ -20,7 +20,7 @@ use uv_distribution_types::{
 };
 use uv_fs::Simplified;
 use uv_install_wheel::LinkMode;
-use uv_installer::SitePackages;
+use uv_installer::{SitePackages, SyncModel};
 use uv_normalize::{DefaultExtras, DefaultGroups};
 use uv_pypi_types::Conflicts;
 use uv_python::{
@@ -531,6 +531,7 @@ pub(crate) async fn pip_sync(
     match operations::install(
         &resolution,
         site_packages,
+        SyncModel::Stateful,
         Modifications::Exact,
         &reinstall,
         &build_options,

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

@@ -23,7 +23,7 @@ use uv_distribution_types::{
 };
 use uv_fs::{CWD, LockedFile, Simplified};
 use uv_git::ResolvedRepositoryReference;
-use uv_installer::{SatisfiesResult, SitePackages};
+use uv_installer::{SatisfiesResult, SitePackages, SyncModel};
 use uv_normalize::{DEV_DEPENDENCIES, DefaultGroups, ExtraName, GroupName, PackageName};
 use uv_pep440::{TildeVersionSpecifier, Version, VersionSpecifiers};
 use uv_pep508::MarkerTreeContents;
@@ -2158,6 +2158,7 @@ pub(crate) async fn sync_environment(
     pip::operations::install(
         resolution,
         site_packages,
+        SyncModel::Stateless,
         modifications,
         reinstall,
         build_options,
@@ -2281,6 +2282,7 @@ pub(crate) async fn update_environment(
             &constraints,
             &overrides,
             &marker_env,
+            SyncModel::Stateless,
             config_setting,
             config_settings_package,
             &extra_build_requires,
@@ -2428,6 +2430,7 @@ pub(crate) async fn update_environment(
     let changelog = pip::operations::install(
         &resolution,
         site_packages,
+        SyncModel::Stateless,
         modifications,
         reinstall,
         build_options,

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

@@ -25,7 +25,7 @@ use uv_distribution::LoweredExtraBuildDependencies;
 use uv_distribution_types::Requirement;
 use uv_fs::which::is_executable;
 use uv_fs::{PythonExt, Simplified, create_symlink};
-use uv_installer::{SatisfiesResult, SitePackages};
+use uv_installer::{SatisfiesResult, SitePackages, SyncModel};
 use uv_normalize::{DefaultExtras, DefaultGroups, PackageName};
 use uv_python::{
     EnvironmentPreference, Interpreter, PyVenvConfiguration, PythonDownloads, PythonEnvironment,
@@ -1363,6 +1363,7 @@ fn can_skip_ephemeral(
         &spec.constraints,
         &spec.overrides,
         &interpreter.resolver_marker_environment(),
+        SyncModel::Stateless,
         config_setting,
         config_settings_package,
         &extra_build_requires,

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

@@ -19,11 +19,10 @@ use uv_configuration::{
 use uv_dispatch::BuildDispatch;
 use uv_distribution::LoweredExtraBuildDependencies;
 use uv_distribution_types::{
-    BuiltDist, DirectorySourceDist, Dist, Index, Name, Requirement, Resolution, ResolvedDist,
+    DirectorySourceDist, Dist, Index, Requirement, Resolution, ResolvedDist, SourceDist,
-    SourceDist,
 };
 use uv_fs::{PortablePathBuf, Simplified};
-use uv_installer::SitePackages;
+use uv_installer::{SitePackages, SyncModel};
 use uv_normalize::{DefaultExtras, DefaultGroups, PackageName};
 use uv_pep508::{MarkerTree, VersionOrUrl};
 use uv_pypi_types::{ParsedArchiveUrl, ParsedGitUrl, ParsedUrl};
@@ -787,67 +786,13 @@ pub(super) async fn do_sync(
 
     let site_packages = SitePackages::from_environment(venv)?;
 
-    // When --no-sources is used, force reinstall only when the current install is editable/URL
-    // but the resolution selects a registry distribution for that package. This avoids
-    // unnecessary reinstalls for packages that are legitimately specified via direct URL.
-    let reinstall = if matches!(sources, uv_configuration::SourceStrategy::Disabled) {
-        tracing::debug!("Sources are disabled; evaluating packages to selectively reinstall");
-
-        // Collect package names which the resolution intends to install from a registry.
-        let resolved_registry_names = {
-            let mut names = std::collections::HashSet::new();
-            for resolved in resolution.distributions() {
-                if let ResolvedDist::Installable { dist, .. } = resolved {
-                    match dist.as_ref() {
-                        Dist::Built(BuiltDist::Registry(_))
-                        | Dist::Source(SourceDist::Registry(_)) => {
-                            names.insert(dist.name().clone());
-                        }
-                        _ => {}
-                    }
-                }
-            }
-            names
-        };
-
-        let mut updated_reinstall = reinstall.clone();
-        for dist in site_packages.iter() {
-            let is_url_like = matches!(
-                dist,
-                uv_distribution_types::InstalledDist::Url(_)
-                    | uv_distribution_types::InstalledDist::LegacyEditable(_)
-            );
-            if is_url_like && resolved_registry_names.contains(dist.name()) {
-                tracing::debug!(
-                    "Marking package for reinstall due to --no-sources registry preference: {}",
-                    dist.name()
-                );
-                updated_reinstall = match updated_reinstall {
-                    uv_configuration::Reinstall::None => {
-                        uv_configuration::Reinstall::Packages(vec![dist.name().clone()], Vec::new())
-                    }
-                    uv_configuration::Reinstall::All => updated_reinstall,
-                    uv_configuration::Reinstall::Packages(mut packages, paths) => {
-                        if !packages.contains(dist.name()) {
-                            packages.push(dist.name().clone());
-                        }
-                        uv_configuration::Reinstall::Packages(packages, paths)
-                    }
-                };
-            }
-        }
-
-        updated_reinstall
-    } else {
-        reinstall.clone()
-    };
-
     // Sync the environment.
     operations::install(
         &resolution,
         site_packages,
+        SyncModel::Stateless,
         modifications,
-        &reinstall,
+        reinstall,
         build_options,
         link_mode,
         compile_bytecode,

crates/uv/src/commands/tool/run.rs

@@ -25,7 +25,7 @@ use uv_distribution_types::{
     UnresolvedRequirement, UnresolvedRequirementSpecification,
 };
 use uv_fs::Simplified;
-use uv_installer::{SatisfiesResult, SitePackages};
+use uv_installer::{SatisfiesResult, SitePackages, SyncModel};
 use uv_normalize::PackageName;
 use uv_pep440::{VersionSpecifier, VersionSpecifiers};
 use uv_pep508::MarkerTree;
@@ -972,6 +972,7 @@ async fn get_or_create_environment(
                             constraints.iter(),
                             overrides.iter(),
                             &interpreter.resolver_marker_environment(),
+                            SyncModel::Stateless,
                             config_setting,
                             config_settings_package,
                             &extra_build_requires,