## Summary

A small follow-up to #11824.

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## Summary

This pull request introduces validation for unique index names in the
`tool.uv.index` field and adds corresponding tests to ensure the
functionality. The most important changes include adding a custom
deserializer function, updating the `ToolUv` struct to use the new
deserializer, and adding tests to verify the behavior.

Validation and deserialization:

*
[`crates/uv-workspace/src/pyproject.rs`](diffhunk://#diff-e12cd255985adfd45ab06f398cb420d2f543841ccbeea4175ccf827aa9215b9dR283-R311):
Added a custom deserializer function `deserialize_index_vec` to validate
that index names in the `tool.uv.index` field are unique.
*
[`crates/uv-workspace/src/pyproject.rs`](diffhunk://#diff-e12cd255985adfd45ab06f398cb420d2f543841ccbeea4175ccf827aa9215b9dR374):
Updated the `ToolUv` struct to use the `deserialize_index_vec` function
for the `index` field.

Testing:

*
[`crates/uv/tests/it/lock.rs`](diffhunk://#diff-82edd36151736f44055f699a34c8b19a63ffc4cf3c86bf5fb34d69f8ac88a957R15336):
Added a test `lock_repeat_named_index` to verify that duplicate index
names result in an error.
[[1]](diffhunk://#diff-82edd36151736f44055f699a34c8b19a63ffc4cf3c86bf5fb34d69f8ac88a957R15336)
[[2]](diffhunk://#diff-82edd36151736f44055f699a34c8b19a63ffc4cf3c86bf5fb34d69f8ac88a957R15360-R15402)
*
[`crates/uv/tests/it/lock.rs`](diffhunk://#diff-82edd36151736f44055f699a34c8b19a63ffc4cf3c86bf5fb34d69f8ac88a957R15360-R15402):
Added a test `lock_unique_named_index` to verify that unique index names
result in successful lock file generation.

Schema update:

*
[`uv.schema.json`](diffhunk://#diff-c669473b258a19ba6d3557d0369126773b68b27171989f265333a77bc5cb935bR205):
Updated the schema to set the default value of the `index` field to
`null`.

Fixes astral-sh#11804

## Test Plan
### Steps to reproduce and verify the fix:

1. Clone the repository and checkout the feature branch
   ```bash
   git clone https://github.com/astral-sh/uv.git
   cd uv
   git checkout feature/warn-duplicate-index-names
   ```

2. Build the modified binary
   ```bash
   cargo build
   ```

3. Create a test project using the system installed uv
   ```bash
   uv init uv-test
   cd uv-test
   ```

4. Manually edit pyproject.toml to add duplicate index names
   ```toml
   [[tool.uv.index]]
   name = "alpha_b"
   url = "<omitted>"

   [[tool.uv.index]]
   name = "alpha_b"
   url = "<omitted>"
   ```

5. Try to add a package using the modified binary
   ```bash
   ../target/debug/uv add numpy
   ```

### Results
Before: use release binary
![スクリーンショット 2025-02-27 15 52
28](https://github.com/user-attachments/assets/2823a4b4-b3ba-40aa-aa41-e593d35c3f3b)

After: use self build binary
![スクリーンショット 2025-02-27 15 51
58](https://github.com/user-attachments/assets/9ac773a9-58cd-4d4b-8685-148bf6dc85fb)

Now when attempting to use a pyproject.toml with duplicate index names,
the modified binary correctly detects the issue and produces an error
message:
```
error: Failed to parse: `pyproject.toml`
  Caused by: TOML parse error at line 9, column 1
  |
9 | [[tool.uv.index]]
  | ^^^^^^^^^^^^^^^^^
duplicate index name `alpha_b`
```

---------

Co-authored-by: Charlie Marsh <[email protected]>

## Summary

A small follow-up to astral-sh#11824.

This MR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [astral-sh/uv](https://github.com/astral-sh/uv) | patch | `0.6.3` -> `0.6.4` |

MR created with the help of [el-capitano/tools/renovate-bot](https://gitlab.com/el-capitano/tools/renovate-bot).

**Proposed changes to behavior should be submitted there as MRs.**

---

### Release Notes

<details>
<summary>astral-sh/uv (astral-sh/uv)</summary>

### [`v0.6.4`](https://github.com/astral-sh/uv/blob/HEAD/CHANGELOG.md#064)

[Compare Source](astral-sh/uv@0.6.3...0.6.4)

##### Enhancements

-   Upgrade pypy3.10 to v7.3.19 ([#&#8203;11814](astral-sh/uv#11814))
-   Allow configuring log verbosity from the CLI (i.e., `-vvv`) ([#&#8203;11758](astral-sh/uv#11758))
-   Warn when duplicate index names found in single file ([#&#8203;11824](astral-sh/uv#11824))

##### Bug fixes

-   Always store registry index on resolution packages ([#&#8203;11815](astral-sh/uv#11815))
-   Avoid error on relative paths in `uv tool uninstall` ([#&#8203;11889](astral-sh/uv#11889))
-   Avoid silently dropping errors in directory enumeration ([#&#8203;11890](astral-sh/uv#11890))
-   Disable interactive git terminal prompts during fetches ([#&#8203;11744](astral-sh/uv#11744))
-   Discover Windows registry (PEP 514) Python versions across 32/64-bit ([#&#8203;11801](astral-sh/uv#11801))
-   Don't panic on Ctrl-C in confirm prompt ([#&#8203;11706](astral-sh/uv#11706))
-   Fix non-directory in workspace on Windows ([#&#8203;11833](astral-sh/uv#11833))
-   Make interpreter caching robust to OS upgrades ([#&#8203;11875](astral-sh/uv#11875))
-   Respect `include-system-site-packages` in layered environments ([#&#8203;11873](astral-sh/uv#11873))
-   Suggest `uv tool update-shell` in PowerShell ([#&#8203;11846](astral-sh/uv#11846))
-   Update code page to `65001` before setting environment variables in virtual environments ([#&#8203;11831](astral-sh/uv#11831))
-   Use hash instead of full wheel name in wheels bucket ([#&#8203;11738](astral-sh/uv#11738))
-   Fix version string truncation while generating cache_key ([#&#8203;11830](astral-sh/uv#11830))
-   Explicitly handle ctrl-c in confirmation prompt instead of using a signal handler ([#&#8203;11897](astral-sh/uv#11897))

##### Performance

-   Avoid cloning to string when creating cache path ([#&#8203;11772](astral-sh/uv#11772))
-   Avoid redundant clones in version containment check ([#&#8203;11767](astral-sh/uv#11767))
-   Avoid string allocation when enumerating tool names ([#&#8203;11910](astral-sh/uv#11910))
-   Avoid using owned `String` for package name constructors ([#&#8203;11768](astral-sh/uv#11768))
-   Avoid using owned `String` in deserializers ([#&#8203;11764](astral-sh/uv#11764))
-   Migrate to `zlib-rs` (again) ([#&#8203;11894](astral-sh/uv#11894))
-   Remove unnecessary clones when adding package names ([#&#8203;11771](astral-sh/uv#11771))
-   Skip unquote allocation for non-quoted strings ([#&#8203;11813](astral-sh/uv#11813))
-   Use `SmallString` for filenames and URLs ([#&#8203;11765](astral-sh/uv#11765))
-   Use a Boxed slice for version specifiers ([#&#8203;11766](astral-sh/uv#11766))
-   Use matches over contains for extra value parsing ([#&#8203;11770](astral-sh/uv#11770))

##### Documentation

-   Avoid fallback to PyPI in mixed CPU/CUDA example ([#&#8203;11115](astral-sh/uv#11115))
-   Docs: Clarify that setting cache-keys overrides defaults ([#&#8203;11895](astral-sh/uv#11895))
-   Document our MSRV policy ([#&#8203;11898](astral-sh/uv#11898))
-   Fix reference to macOS cache path ([#&#8203;11845](astral-sh/uv#11845))
-   Fix typo in `no_default_groups` documentation and changelog ([#&#8203;11928](astral-sh/uv#11928))
-   Update the "Locking and syncing" page ([#&#8203;11647](astral-sh/uv#11647))
-   Update alternative indexes documentation to use new interface ([#&#8203;10826](astral-sh/uv#10826))

</details>

---

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