diff --git a/crates/uv/tests/lock.rs b/crates/uv/tests/lock.rs
index 038350015e02..ebf8361118d6 100644
--- a/crates/uv/tests/lock.rs
+++ b/crates/uv/tests/lock.rs
@@ -7502,3 +7502,134 @@ fn lock_transitive_extra() -> Result<()> {
 
     Ok(())
 }
+
+/// If a source is provided via `tool.uv.sources` _and_ a URL is provided in `project.dependencies`,
+/// we raise an error.
+#[test]
+fn lock_mismatched_sources() -> 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 = [
+            "uv-public-pypackage @ git+https://github.com/astral-test/uv-public-pypackage@0.0.2",
+        ]
+
+        [tool.uv.sources]
+        uv-public-pypackage = { git = "https://github.com/astral-test/uv-public-pypackage", tag = "0.0.1" }
+        "#,
+    )?;
+
+    uv_snapshot!(context.filters(), context.lock(), @r###"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    warning: `uv lock` is experimental and may change without warning
+    warning: `uv.sources` is experimental and may change without warning
+    error: Failed to download and build: `project @ file://[TEMP_DIR]/`
+      Caused by: Failed to parse entry for: `uv-public-pypackage`
+      Caused by: Can't combine URLs from both `project.dependencies` and `tool.uv.sources`
+    "###);
+
+    Ok(())
+}
+
+/// If a source is provided via `tool.uv.sources`, we don't enforce that the declared dependency
+/// version is satisfied.
+///
+/// See: <https://github.com/astral-sh/uv/issues/4604>
+#[test]
+fn lock_mismatched_versions() -> 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 = [
+            "uv-public-pypackage==0.0.2",
+        ]
+
+        [tool.uv.sources]
+        uv-public-pypackage = { git = "https://github.com/astral-test/uv-public-pypackage", tag = "0.0.1" }
+        "#,
+    )?;
+
+    uv_snapshot!(context.filters(), context.lock(), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    warning: `uv lock` is experimental and may change without warning
+    warning: `uv.sources` 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 = "project"
+        version = "0.1.0"
+        source = { editable = "." }
+        dependencies = [
+            { name = "uv-public-pypackage" },
+        ]
+
+        [[package]]
+        name = "uv-public-pypackage"
+        version = "0.1.0"
+        source = { git = "https://github.com/astral-test/uv-public-pypackage?tag=0.0.1#0dacfd662c64cb4ceb16e6cf65a157a8b715b979" }
+        "###
+        );
+    });
+
+    // 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
+    warning: `uv.sources` is experimental and may change without warning
+    Resolved 2 packages in [TIME]
+    "###);
+
+    // Install from the lockfile.
+    uv_snapshot!(context.filters(), context.sync().arg("--frozen"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    warning: `uv sync` is experimental and may change without warning
+    Prepared 2 packages in [TIME]
+    Installed 2 packages in [TIME]
+     + project==0.1.0 (from file://[TEMP_DIR]/)
+     + uv-public-pypackage==0.1.0 (from git+https://github.com/astral-test/uv-public-pypackage@0dacfd662c64cb4ceb16e6cf65a157a8b715b979)
+    "###);
+
+    Ok(())
+}