Invalidate uv.lock if registry sources are removed

crates/distribution-types/src/file.rs

@@ -1,3 +1,4 @@
+use std::borrow::Cow;
 use std::fmt::{self, Display, Formatter};
 use std::path::PathBuf;
 use std::str::FromStr;
@@ -197,6 +198,12 @@ impl From<&Url> for UrlString {
     }
 }
 
+impl From<Cow<'_, Url>> for UrlString {
+    fn from(value: Cow<'_, Url>) -> Self {
+        UrlString(value.to_string())
+    }
+}
+
 impl From<VerbatimUrl> for UrlString {
     fn from(value: VerbatimUrl) -> Self {
         UrlString(value.raw().to_string())

crates/distribution-types/src/index_url.rs

@@ -348,6 +348,15 @@ impl IndexLocations {
             no_index: self.no_index || no_index,
         }
     }
+
+    /// Returns `true` if no index configuration is set, i.e., the [`IndexLocations`] matches the
+    /// default configuration.
+    pub fn is_none(&self) -> bool {
+        self.index.is_none()
+            && self.extra_index.is_empty()
+            && self.flat_index.is_empty()
+            && !self.no_index
+    }
 }
 
 impl<'a> IndexLocations {

crates/uv-resolver/src/lock.rs

@@ -1210,10 +1210,19 @@ impl Package {
         &self.id.version
     }
 
+    /// Return the fork markers for this package, if any.
     pub fn fork_markers(&self) -> Option<&BTreeSet<MarkerTree>> {
         self.fork_markers.as_ref()
     }
 
+    /// Return the index URL for this package, if it is a registry source.
+    pub fn index(&self) -> Option<&UrlString> {
+        match &self.id.source {
+            Source::Registry(url) => Some(url),
+            _ => None,
+        }
+    }
+
     /// Returns a [`VersionId`] for this package that can be used for resolution.
     fn version_id(&self, workspace_root: &Path) -> Result<VersionId, LockError> {
         match &self.id.source {

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

@@ -8,7 +8,9 @@ use owo_colors::OwoColorize;
 use rustc_hash::{FxBuildHasher, FxHashMap};
 use tracing::debug;
 
-use distribution_types::{Diagnostic, UnresolvedRequirementSpecification};
+use distribution_types::{
+    Diagnostic, FlatIndexLocation, IndexUrl, UnresolvedRequirementSpecification, UrlString,
+};
 use pep440_rs::Version;
 use uv_auth::store_credentials_from_url;
 use uv_cache::Cache;
@@ -427,7 +429,53 @@ async fn do_lock(
         existing_lock.and_then(|lock| lock.fork_markers().clone())
     });
 
-    let resolution = match existing_lock.filter(|_| upgrade.is_none()) {
+    // If any upgrades are specified, don't use the existing lockfile.
+    let existing_lock = existing_lock.filter(|_| upgrade.is_none());
+
+    // If the user provided at least one index URL (from the command line, or from a configuration
+    // file), don't use the existing lockfile if it references any registries that are no longer
+    // included in the current configuration.
+    let existing_lock = existing_lock.filter(|lock| {
+        //  If _no_ indexes were provided, we assume that the user wants to reuse the existing
+        // distributions, even though a failure to reuse the lockfile will result in re-resolving
+        // against PyPI by default.
+        if settings.index_locations.is_none() {
+            return true;
+        }
+
+        // Collect the set of available indexes (both `--index-url` and `--find-links` entries).
+        let indexes = settings
+            .index_locations
+            .indexes()
+            .map(IndexUrl::redacted)
+            .chain(
+                settings
+                    .index_locations
+                    .flat_index()
+                    .map(FlatIndexLocation::redacted),
+            )
+            .map(UrlString::from)
+            .collect::<BTreeSet<_>>();
+
+        // Find any packages in the lockfile that reference a registry that is no longer included in
+        // the current configuration.
+        for package in lock.packages() {
+            let Some(index) = package.index() else {
+                continue;
+            };
+            if !indexes.contains(index) {
+                let _ = writeln!(
+                    printer.stderr(),
+                    "Ignoring existing lockfile due to removal of referenced registry: {index}"
+                );
+                return false;
+            }
+        }
+
+        true
+    });
+
+    let resolution = match existing_lock {
         None => None,
 
         // Try to resolve using metadata in the lockfile.

crates/uv/tests/lock.rs

@@ -7652,3 +7652,121 @@ fn unconditional_overlapping_marker_disjoint_version_constraints() -> Result<()>
 
     Ok(())
 }
+
+/// Change indexes between locking operations.
+#[test]
+fn lock_change_index() -> Result<()> {
+    let context = TestContext::new("3.12");
+
+    let pyproject_toml = context.temp_dir.child("pyproject.toml");
+    pyproject_toml.write_str(
+        r#"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+        dependencies = ["iniconfig"]
+        "#,
+    )?;
+
+    uv_snapshot!(context.filters(), context.lock().arg("--index-url").arg("https://public:heron@pypi-proxy.fly.dev/basic-auth/simple"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    warning: `uv lock` is experimental and may change without warning
+    Resolved 2 packages in [TIME]
+    "###);
+
+    let lock = fs_err::read_to_string(context.temp_dir.join("uv.lock")).unwrap();
+
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            lock, @r###"
+        version = 1
+        requires-python = ">=3.12"
+
+        [options]
+        exclude-newer = "2024-03-25 00:00:00 UTC"
+
+        [[package]]
+        name = "iniconfig"
+        version = "2.0.0"
+        source = { registry = "https://pypi-proxy.fly.dev/basic-auth/simple" }
+        sdist = { url = "https://pypi-proxy.fly.dev/basic-auth/files/packages/d7/4b/cbd8e699e64a6f16ca3a8220661b5f83792b3017d0f79807cb8708d33913/iniconfig-2.0.0.tar.gz", hash = "sha256:2d91e135bf72d31a410b17c16da610a82cb55f6b0477d1a902134b24a455b8b3", size = 4646 }
+        wheels = [
+            { url = "https://pypi-proxy.fly.dev/basic-auth/files/packages/ef/a6/62565a6e1cf69e10f5727360368e451d4b7f58beeac6173dc9db836a5b46/iniconfig-2.0.0-py3-none-any.whl", hash = "sha256:b6a85871a79d2e3b22d2d1b94ac2824226a63c6b741c88f7ae975f18b6778374", size = 5892 },
+        ]
+
+        [[package]]
+        name = "project"
+        version = "0.1.0"
+        source = { editable = "." }
+        dependencies = [
+            { name = "iniconfig" },
+        ]
+        "###
+        );
+    });
+
+    // Re-run against PyPI.
+    uv_snapshot!(context.filters(), context.lock().arg("--index-url").arg("https://pypi.org/simple"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    warning: `uv lock` is experimental and may change without warning
+    Ignoring existing lockfile due to removal of referenced registry: https://pypi-proxy.fly.dev/basic-auth/simple
+    Resolved 2 packages in [TIME]
+    "###);
+
+    let lock = fs_err::read_to_string(context.temp_dir.join("uv.lock")).unwrap();
+
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            lock, @r###"
+        version = 1
+        requires-python = ">=3.12"
+
+        [options]
+        exclude-newer = "2024-03-25 00:00:00 UTC"
+
+        [[package]]
+        name = "iniconfig"
+        version = "2.0.0"
+        source = { registry = "https://pypi.org/simple" }
+        sdist = { url = "https://files.pythonhosted.org/packages/d7/4b/cbd8e699e64a6f16ca3a8220661b5f83792b3017d0f79807cb8708d33913/iniconfig-2.0.0.tar.gz", hash = "sha256:2d91e135bf72d31a410b17c16da610a82cb55f6b0477d1a902134b24a455b8b3", size = 4646 }
+        wheels = [
+            { url = "https://files.pythonhosted.org/packages/ef/a6/62565a6e1cf69e10f5727360368e451d4b7f58beeac6173dc9db836a5b46/iniconfig-2.0.0-py3-none-any.whl", hash = "sha256:b6a85871a79d2e3b22d2d1b94ac2824226a63c6b741c88f7ae975f18b6778374", size = 5892 },
+        ]
+
+        [[package]]
+        name = "project"
+        version = "0.1.0"
+        source = { editable = "." }
+        dependencies = [
+            { name = "iniconfig" },
+        ]
+        "###
+        );
+    });
+
+    // Re-run with `--locked`.
+    uv_snapshot!(context.filters(), context.lock().arg("--locked"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    warning: `uv lock` is experimental and may change without warning
+    Resolved 2 packages in [TIME]
+    "###);
+
+    Ok(())
+}