Avoid creating lockfile

crates/uv-cli/src/lib.rs

@@ -3135,8 +3135,7 @@ pub struct SyncArgs {
     #[arg(long, conflicts_with = "all_packages")]
     pub package: Option<PackageName>,
 
-    /// Sync the virtual environment for the specified PEP 723 Python script, rather than the current
-    /// project.
+    /// Sync the environment for a Python script, rather than the current project.
     ///
     /// If provided, uv will sync the dependencies based on the script's inline metadata table, in
     /// adherence with PEP 723.
@@ -3146,7 +3145,19 @@ pub struct SyncArgs {
         conflicts_with = "all_packages",
         conflicts_with = "package",
         conflicts_with = "no_install_project",
-        conflicts_with = "no_install_workspace"
+        conflicts_with = "no_install_workspace",
+        conflicts_with = "extra",
+        conflicts_with = "all_extras",
+        conflicts_with = "no_extra",
+        conflicts_with = "no_all_extras",
+        conflicts_with = "dev",
+        conflicts_with = "no_dev",
+        conflicts_with = "only_dev",
+        conflicts_with = "group",
+        conflicts_with = "no_group",
+        conflicts_with = "no_default_groups",
+        conflicts_with = "only_group",
+        conflicts_with = "all_groups"
     )]
     pub script: Option<PathBuf>,
 

crates/uv-distribution/src/lib.rs

@@ -3,8 +3,8 @@ pub use download::LocalWheel;
 pub use error::Error;
 pub use index::{BuiltWheelIndex, RegistryWheelIndex};
 pub use metadata::{
-    ArchiveMetadata, BuildRequires, FlatRequiresDist, LoweredRequirement, Metadata, MetadataError,
-    RequiresDist,
+    ArchiveMetadata, BuildRequires, FlatRequiresDist, LoweredRequirement, LoweringError, Metadata,
+    MetadataError, RequiresDist,
 };
 pub use reporter::Reporter;
 pub use source::prune;

crates/uv-distribution/src/metadata/mod.rs

@@ -13,7 +13,7 @@ use uv_workspace::WorkspaceError;
 
 pub use crate::metadata::build_requires::BuildRequires;
 pub use crate::metadata::lowering::LoweredRequirement;
-use crate::metadata::lowering::LoweringError;
+pub use crate::metadata::lowering::LoweringError;
 pub use crate::metadata::requires_dist::{FlatRequiresDist, RequiresDist};
 
 mod build_requires;

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

@@ -1,7 +1,6 @@
 use std::borrow::Cow;
 use std::collections::{BTreeMap, BTreeSet};
 use std::fmt::Write;
-use std::ops::Deref;
 use std::path::{Path, PathBuf};
 use std::sync::Arc;
 
@@ -14,10 +13,10 @@ use uv_cache_key::cache_digest;
 use uv_client::{BaseClientBuilder, Connectivity, FlatIndexClient, RegistryClientBuilder};
 use uv_configuration::{
     Concurrency, Constraints, DevGroupsManifest, DevGroupsSpecification, DryRun,
-    ExtrasSpecification, PreviewMode, Reinstall, TrustedHost, Upgrade,
+    ExtrasSpecification, PreviewMode, Reinstall, SourceStrategy, TrustedHost, Upgrade,
 };
 use uv_dispatch::{BuildDispatch, SharedState};
-use uv_distribution::DistributionDatabase;
+use uv_distribution::{DistributionDatabase, LoweredRequirement};
 use uv_distribution_types::{
     Index, Resolution, UnresolvedRequirement, UnresolvedRequirementSpecification,
 };
@@ -227,6 +226,9 @@ pub(crate) enum ProjectError {
     #[error(transparent)]
     Metadata(#[from] uv_distribution::MetadataError),
 
+    #[error(transparent)]
+    Lowering(#[from] uv_distribution::LoweringError),
+
     #[error(transparent)]
     PyprojectMut(#[from] uv_workspace::pyproject_mut::Error),
 
@@ -1224,7 +1226,7 @@ impl ProjectEnvironment {
     }
 }
 
-impl Deref for ProjectEnvironment {
+impl std::ops::Deref for ProjectEnvironment {
     type Target = PythonEnvironment;
 
     fn deref(&self) -> &Self::Target {
@@ -1389,7 +1391,7 @@ impl ScriptEnvironment {
     }
 }
 
-impl Deref for ScriptEnvironment {
+impl std::ops::Deref for ScriptEnvironment {
     type Target = PythonEnvironment;
 
     fn deref(&self) -> &Self::Target {
@@ -1911,6 +1913,7 @@ pub(crate) async fn update_environment(
     native_tls: bool,
     allow_insecure_host: &[TrustedHost],
     cache: &Cache,
+    dry_run: DryRun,
     printer: Printer,
     preview: PreviewMode,
 ) -> Result<EnvironmentUpdate, ProjectError> {
@@ -2026,7 +2029,6 @@ pub(crate) async fn update_environment(
     // optional on the downstream APIs.
     let build_constraints = Constraints::default();
     let build_hasher = HashStrategy::default();
-    let dry_run = DryRun::default();
     let extras = ExtrasSpecification::default();
     let groups = DevGroupsSpecification::default();
     let hasher = HashStrategy::default();
@@ -2297,6 +2299,113 @@ pub(crate) fn detect_conflicts(
     Ok(())
 }
 
+/// Determine the [`RequirementsSpecification`] for a script.
+#[allow(clippy::result_large_err)]
+pub(crate) fn script_specification(
+    script: Pep723ItemRef<'_>,
+    settings: ResolverSettingsRef,
+) -> Result<Option<RequirementsSpecification>, ProjectError> {
+    let Some(dependencies) = script.metadata().dependencies.as_ref() else {
+        return Ok(None);
+    };
+
+    // Determine the working directory for the script.
+    let script_dir = match &script {
+        Pep723ItemRef::Script(script) => std::path::absolute(&script.path)?
+            .parent()
+            .expect("script path has no parent")
+            .to_owned(),
+        Pep723ItemRef::Stdin(..) | Pep723ItemRef::Remote(..) => std::env::current_dir()?,
+    };
+
+    // Collect any `tool.uv.index` from the script.
+    let empty = Vec::default();
+    let script_indexes = match settings.sources {
+        SourceStrategy::Enabled => script
+            .metadata()
+            .tool
+            .as_ref()
+            .and_then(|tool| tool.uv.as_ref())
+            .and_then(|uv| uv.top_level.index.as_deref())
+            .unwrap_or(&empty),
+        SourceStrategy::Disabled => &empty,
+    };
+
+    // Collect any `tool.uv.sources` from the script.
+    let empty = BTreeMap::default();
+    let script_sources = match settings.sources {
+        SourceStrategy::Enabled => script
+            .metadata()
+            .tool
+            .as_ref()
+            .and_then(|tool| tool.uv.as_ref())
+            .and_then(|uv| uv.sources.as_ref())
+            .unwrap_or(&empty),
+        SourceStrategy::Disabled => &empty,
+    };
+
+    let requirements = dependencies
+        .iter()
+        .cloned()
+        .flat_map(|requirement| {
+            LoweredRequirement::from_non_workspace_requirement(
+                requirement,
+                script_dir.as_ref(),
+                script_sources,
+                script_indexes,
+                settings.index_locations,
+            )
+            .map_ok(LoweredRequirement::into_inner)
+        })
+        .collect::<Result<_, _>>()?;
+    let constraints = script
+        .metadata()
+        .tool
+        .as_ref()
+        .and_then(|tool| tool.uv.as_ref())
+        .and_then(|uv| uv.constraint_dependencies.as_ref())
+        .into_iter()
+        .flatten()
+        .cloned()
+        .flat_map(|requirement| {
+            LoweredRequirement::from_non_workspace_requirement(
+                requirement,
+                script_dir.as_ref(),
+                script_sources,
+                script_indexes,
+                settings.index_locations,
+            )
+            .map_ok(LoweredRequirement::into_inner)
+        })
+        .collect::<Result<Vec<_>, _>>()?;
+    let overrides = script
+        .metadata()
+        .tool
+        .as_ref()
+        .and_then(|tool| tool.uv.as_ref())
+        .and_then(|uv| uv.override_dependencies.as_ref())
+        .into_iter()
+        .flatten()
+        .cloned()
+        .flat_map(|requirement| {
+            LoweredRequirement::from_non_workspace_requirement(
+                requirement,
+                script_dir.as_ref(),
+                script_sources,
+                script_indexes,
+                settings.index_locations,
+            )
+            .map_ok(LoweredRequirement::into_inner)
+        })
+        .collect::<Result<Vec<_>, _>>()?;
+
+    Ok(Some(RequirementsSpecification::from_overrides(
+        requirements,
+        constraints,
+        overrides,
+    )))
+}
+
 /// Warn if the user provides (e.g.) an `--index-url` in a requirements file.
 fn warn_on_requirements_txt_setting(
     spec: &RequirementsSpecification,

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

@@ -1,5 +1,4 @@
 use std::borrow::Cow;
-use std::collections::BTreeMap;
 use std::ffi::OsString;
 use std::fmt::Write;
 use std::io::Read;
@@ -18,9 +17,8 @@ use uv_cli::ExternalCommand;
 use uv_client::{BaseClientBuilder, Connectivity};
 use uv_configuration::{
     Concurrency, DevGroupsSpecification, DryRun, EditableMode, ExtrasSpecification, InstallOptions,
-    PreviewMode, SourceStrategy, TrustedHost,
+    PreviewMode, TrustedHost,
 };
-use uv_distribution::LoweredRequirement;
 use uv_fs::which::is_executable;
 use uv_fs::{PythonExt, Simplified};
 use uv_installer::{SatisfiesResult, SitePackages};
@@ -46,9 +44,10 @@ use crate::commands::project::install_target::InstallTarget;
 use crate::commands::project::lock::LockMode;
 use crate::commands::project::lock_target::LockTarget;
 use crate::commands::project::{
-    default_dependency_groups, update_environment, validate_project_requires_python,
-    DependencyGroupsTarget, EnvironmentSpecification, ProjectEnvironment, ProjectError,
-    ScriptEnvironment, ScriptInterpreter, UniversalState, WorkspacePython,
+    default_dependency_groups, script_specification, update_environment,
+    validate_project_requires_python, DependencyGroupsTarget, EnvironmentSpecification,
+    ProjectEnvironment, ProjectError, ScriptEnvironment, ScriptInterpreter, UniversalState,
+    WorkspacePython,
 };
 use crate::commands::reporters::PythonDownloadReporter;
 use crate::commands::run::run_to_completion;
@@ -318,98 +317,8 @@ pub(crate) async fn run(
                 );
             }
 
-            // Determine the working directory for the script.
-            let script_dir = match &script {
-                Pep723Item::Script(script) => std::path::absolute(&script.path)?
-                    .parent()
-                    .expect("script path has no parent")
-                    .to_owned(),
-                Pep723Item::Stdin(..) | Pep723Item::Remote(..) => std::env::current_dir()?,
-            };
-            let metadata = script.metadata();
-
             // Install the script requirements, if necessary. Otherwise, use an isolated environment.
-            if let Some(dependencies) = metadata.dependencies.as_ref() {
-                // Collect any `tool.uv.index` from the script.
-                let empty = Vec::default();
-                let script_indexes = match settings.sources {
-                    SourceStrategy::Enabled => metadata
-                        .tool
-                        .as_ref()
-                        .and_then(|tool| tool.uv.as_ref())
-                        .and_then(|uv| uv.top_level.index.as_deref())
-                        .unwrap_or(&empty),
-                    SourceStrategy::Disabled => &empty,
-                };
-
-                // Collect any `tool.uv.sources` from the script.
-                let empty = BTreeMap::default();
-                let script_sources = match settings.sources {
-                    SourceStrategy::Enabled => metadata
-                        .tool
-                        .as_ref()
-                        .and_then(|tool| tool.uv.as_ref())
-                        .and_then(|uv| uv.sources.as_ref())
-                        .unwrap_or(&empty),
-                    SourceStrategy::Disabled => &empty,
-                };
-
-                let requirements = dependencies
-                    .iter()
-                    .cloned()
-                    .flat_map(|requirement| {
-                        LoweredRequirement::from_non_workspace_requirement(
-                            requirement,
-                            script_dir.as_ref(),
-                            script_sources,
-                            script_indexes,
-                            &settings.index_locations,
-                        )
-                        .map_ok(LoweredRequirement::into_inner)
-                    })
-                    .collect::<Result<_, _>>()?;
-                let constraints = metadata
-                    .tool
-                    .as_ref()
-                    .and_then(|tool| tool.uv.as_ref())
-                    .and_then(|uv| uv.constraint_dependencies.as_ref())
-                    .into_iter()
-                    .flatten()
-                    .cloned()
-                    .flat_map(|requirement| {
-                        LoweredRequirement::from_non_workspace_requirement(
-                            requirement,
-                            script_dir.as_ref(),
-                            script_sources,
-                            script_indexes,
-                            &settings.index_locations,
-                        )
-                        .map_ok(LoweredRequirement::into_inner)
-                    })
-                    .collect::<Result<Vec<_>, _>>()?;
-                let overrides = metadata
-                    .tool
-                    .as_ref()
-                    .and_then(|tool| tool.uv.as_ref())
-                    .and_then(|uv| uv.override_dependencies.as_ref())
-                    .into_iter()
-                    .flatten()
-                    .cloned()
-                    .flat_map(|requirement| {
-                        LoweredRequirement::from_non_workspace_requirement(
-                            requirement,
-                            script_dir.as_ref(),
-                            script_sources,
-                            script_indexes,
-                            &settings.index_locations,
-                        )
-                        .map_ok(LoweredRequirement::into_inner)
-                    })
-                    .collect::<Result<Vec<_>, _>>()?;
-
-                let spec =
-                    RequirementsSpecification::from_overrides(requirements, constraints, overrides);
-
+            if let Some(spec) = script_specification((&script).into(), settings.as_ref().into())? {
                 let environment = ScriptEnvironment::get_or_init(
                     (&script).into(),
                     python.as_deref().map(PythonRequest::parse),
@@ -449,6 +358,7 @@ pub(crate) async fn run(
                     native_tls,
                     allow_insecure_host,
                     cache,
+                    DryRun::Disabled,
                     printer,
                     preview,
                 )