WIP unused sources warning

Cargo.lock

@@ -5084,6 +5084,7 @@ dependencies = [
  "futures",
  "indoc",
  "insta",
+ "itertools 0.14.0",
  "nanoid",
  "owo-colors",
  "reqwest",
@@ -5117,6 +5118,7 @@ dependencies = [
  "uv-pypi-types",
  "uv-redacted",
  "uv-types",
+ "uv-warnings",
  "uv-workspace",
  "walkdir",
  "zip",

crates/uv-distribution/Cargo.toml

@@ -35,12 +35,14 @@ uv-platform-tags = { workspace = true }
 uv-pypi-types = { workspace = true }
 uv-redacted = { workspace = true }
 uv-types = { workspace = true }
+uv-warnings = { workspace = true }
 uv-workspace = { workspace = true }
 
 anyhow = { workspace = true }
 either = { workspace = true }
 fs-err = { workspace = true }
 futures = { workspace = true }
+itertools = { workspace = true }
 nanoid = { workspace = true }
 owo-colors = { workspace = true }
 reqwest = { workspace = true }

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

@@ -1,4 +1,4 @@
-use std::collections::BTreeMap;
+use std::collections::{BTreeMap, BTreeSet};
 use std::path::Path;
 
 use uv_configuration::SourceStrategy;
@@ -106,6 +106,8 @@ impl BuildRequires {
                         metadata.name.as_ref(),
                         project_workspace.project_root(),
                         project_sources,
+                        // TODO: make this better lol
+                        &mut BTreeSet::new(),
                         project_indexes,
                         extra.as_deref(),
                         group,
@@ -178,6 +180,8 @@ impl BuildRequires {
                         None,
                         workspace.install_path(),
                         project_sources,
+                        // TODO: make this better lol
+                        &mut BTreeSet::new(),
                         project_indexes,
                         extra.as_deref(),
                         group,

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

@@ -1,4 +1,4 @@
-use std::collections::BTreeMap;
+use std::collections::{BTreeMap, BTreeSet};
 use std::path::{Path, PathBuf};
 
 use uv_configuration::SourceStrategy;
@@ -142,6 +142,8 @@ impl SourcedDependencyGroups {
                             project.project_name(),
                             project.root(),
                             project_sources,
+                            // TODO: make this better lol
+                            &mut BTreeSet::new(),
                             project_indexes,
                             extra,
                             Some(&group),

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

@@ -1,4 +1,4 @@
-use std::collections::BTreeMap;
+use std::collections::{BTreeMap, BTreeSet};
 use std::io;
 use std::path::{Path, PathBuf};
 
@@ -38,6 +38,7 @@ impl LoweredRequirement {
         project_name: Option<&'data PackageName>,
         project_dir: &'data Path,
         project_sources: &'data BTreeMap<PackageName, Sources>,
+        project_sources_used: &mut BTreeSet<PackageName>,
         project_indexes: &'data [Index],
         extra: Option<&ExtraName>,
         group: Option<&GroupName>,
@@ -47,8 +48,10 @@ impl LoweredRequirement {
     ) -> impl Iterator<Item = Result<Self, LoweringError>> + use<'data> + 'data {
         // Identify the source from the `tool.uv.sources` table.
         let (sources, origin) = if let Some(source) = project_sources.get(&requirement.name) {
+            project_sources_used.insert(requirement.name.clone());
             (Some(source), RequirementOrigin::Project)
         } else if let Some(source) = workspace.sources().get(&requirement.name) {
+            // TODO(jack): Track workplace sources used also.
             (Some(source), RequirementOrigin::Workspace)
         } else {
             (None, RequirementOrigin::Project)

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

@@ -1,13 +1,15 @@
-use std::collections::{BTreeMap, VecDeque};
+use std::collections::{BTreeMap, BTreeSet, VecDeque};
 use std::path::Path;
 use std::slice;
 
+use itertools::Itertools;
 use rustc_hash::FxHashSet;
 
 use uv_configuration::SourceStrategy;
 use uv_distribution_types::{IndexLocations, Requirement};
 use uv_normalize::{ExtraName, GroupName, PackageName};
 use uv_pep508::MarkerTree;
+use uv_warnings::warn_user_once;
 use uv_workspace::dependency_groups::FlatDependencyGroups;
 use uv_workspace::pyproject::{Sources, ToolUvSources};
 use uv_workspace::{DiscoveryOptions, MemberDiscovery, ProjectWorkspace, WorkspaceCache};
@@ -106,6 +108,8 @@ impl RequiresDist {
                 .unwrap_or(&empty),
             SourceStrategy::Disabled => &empty,
         };
+        // Keep track of which sources we use, so we can print a warning for unused ones.
+        let mut project_sources_used = BTreeSet::new();
 
         let dependency_groups = FlatDependencyGroups::from_pyproject_toml(
             project_workspace.current_project().root(),
@@ -133,6 +137,7 @@ impl RequiresDist {
                                 Some(&metadata.name),
                                 project_workspace.project_root(),
                                 project_sources,
+                                &mut project_sources_used,
                                 project_indexes,
                                 extra,
                                 Some(&group),
@@ -175,6 +180,7 @@ impl RequiresDist {
                         Some(&metadata.name),
                         project_workspace.project_root(),
                         project_sources,
+                        &mut project_sources_used,
                         project_indexes,
                         extra.as_deref(),
                         group,
@@ -194,6 +200,21 @@ impl RequiresDist {
             SourceStrategy::Disabled => requires_dist.into_iter().map(Requirement::from).collect(),
         };
 
+        // Warn if we have any unused project sources.
+        let mut unused_source_names = Vec::new();
+        for package_name in project_sources.keys() {
+            if !project_sources_used.contains(package_name) {
+                unused_source_names.push(package_name);
+            }
+        }
+        if !unused_source_names.is_empty() {
+            warn_user_once!(
+                "some {} don't match a direct dependency and have no effect: {}",
+                "[tool.uv.sources]".cyan(),
+                unused_source_names.iter().map(OwoColorize::cyan).join(", "),
+            );
+        }
+
         Ok(Self {
             name: metadata.name,
             requires_dist,