Re: [PATCH v5 1/2] scripts: generate_rust_analyzer.py: add versioning infrastructure

[Tamir Duberstein]

On Thu, Apr 30, 2026 at 8:15 AM Jesung Yang via B4 Relay
<devnull+y.j3ms.n.gmail.com@xxxxxxxxxx> wrote:
>
> From: Jesung Yang <y.j3ms.n@xxxxxxxxx>
>
> Introduce multi-version support for rust-analyzer. The script now
> executes `rust-analyzer --version` to query the version string.
>
> This is a preparatory patch to address inherent method resolution
> failures for primitive types occurring in rust-analyzer v0.3.2693
> (2025-11-24) or later when used with our current `rust-project.json`
> generation logic. Since the actual fix requires using the `sysroot_src`
> field with a feature only available in rust-analyzer v0.3.2727
> (2025-12-22) or later, this infrastructure is necessary to maintain
> compatibility with older rust-analyzer releases.
>
> Signed-off-by: Jesung Yang <y.j3ms.n@xxxxxxxxx>
> ---
>  scripts/generate_rust_analyzer.py | 171 +++++++++++++++++++++++++++++++++++++-
>  1 file changed, 167 insertions(+), 4 deletions(-)
>
> diff --git a/scripts/generate_rust_analyzer.py b/scripts/generate_rust_analyzer.py
> index d5f9a0ca742c..f1828620bbbf 100755
> --- a/scripts/generate_rust_analyzer.py
> +++ b/scripts/generate_rust_analyzer.py
> @@ -4,6 +4,9 @@
>  """
>
>  import argparse
> +from datetime import datetime, date
> +import enum
> +import re
>  import json
>  import logging
>  import os
> @@ -343,6 +346,148 @@ def generate_crates(
>
>      return crates
>
> +
> +Version = tuple[int, int, int]
> +
> +
> +@enum.unique
> +class RaVersionInfo(enum.Enum):
> +    """
> +    Represents rust-analyzer compatibility baselines. Concrete versions are mapped to the most
> +    recent baseline they have reached. Must be in release order.
> +    """

Until this patch this file wrapped at 80 columns.

> +
> +    # NOTE:
> +    # This rust-analyzer release should be kept in sync with our MSRV (currently 1.85.0).
> +    # When the MSRV is bumped, follow the steps below to retrieve the information needed
> +    # to update this:
> +    #
> +    #   1) Clone both Rust and rust-analyzer repositories.
> +    #      ```console
> +    #      $ git clone https://github.com/rust-lang/rust.git
> +    #      $ git clone https://github.com/rust-lang/rust-analyzer.git
> +    #      ```
> +    #   2) Run the following script, providing the new MSRV as an argument.
> +    #      It uses `xdg-open` to open the matching [1] rust-analyzer release page.
> +    #      ```bash
> +    #      #!/usr/bin/env bash
> +    #
> +    #      RUST_VERSION=$1
> +    #      LOOKAHEAD=50
> +    #
> +    #      subject_string=$(
> +    #        git -C ./rust log -n "$LOOKAHEAD" --format='%s' "$RUST_VERSION" \
> +    #          -- src/tools/rust-analyzer | grep 'Merge pull request #'

This grep can be replaced with `--merges` and then you can just use
`-n 1` instead of `-n $LOOKAHEAD`, right?

> +    #      )
> +    #      readarray -t subject_array <<< "$subject_string"
> +    #
> +    #      hash=$(
> +    #        git -C ./rust-analyzer log -n 1 --format='%H' --fixed-strings \
> +    #          "${subject_array[@]/#/--grep=}"
> +    #      )
> +    #
> +    #      tag_predates=$(git -C ./rust-analyzer describe --tags --abbrev=0 "$hash")
> +    #
> +    #      link_prefix="https://github.com/rust-lang/rust-analyzer/releases/tag";
> +    #      xdg-open "$link_prefix/$tag_predates"
> +    #      ```

With or without the `--merges` change, this always takes me to a very
recent tag. It seems like `git log -- src/tools/rust-analyzer` in the
rust repo never shows merge commits?


> +    #   3) Grab the release date and the version string.
> +    #
> +    # [1] Note that rust-analyzer releases may not perfectly align with those shipped
> +    #     in upstream Rust. We take a conservative approach here: use the tag that
> +    #     directly predates the latest merge commit found upstream.
> +    #
> +    # v0.3.2228, released on 2024-12-23; shipped with the rustup 1.85.0 toolchain.
> +    MSRV = (
> +        datetime.strptime("2024-12-23", "%Y-%m-%d"),

Could we use date everywhere? Why datetime?

https://docs.python.org/3/library/datetime.html#datetime.date.strptime

> +        (0, 3, 2228),
> +        (1, 85, 0),
> +    )
> +
> +    def __init__(
> +        self,
> +        release_date: date,
> +        ra_version: Version,
> +        rust_version: Version,
> +    ) -> None:
> +        self.release_date = release_date
> +        self.ra_version = ra_version
> +        self.rust_version = rust_version
> +
> +
> +class RustProject(TypedDict):
> +    crates: List[Crate]
> +    sysroot: str
> +
> +
> +def generate_rust_project(
> +    _version_info: RaVersionInfo,
> +    srctree: pathlib.Path,
> +    objtree: pathlib.Path,
> +    sysroot: pathlib.Path,
> +    sysroot_src: pathlib.Path,
> +    external_src: Optional[pathlib.Path],
> +    cfgs: List[str],
> +    core_edition: str,
> +) -> RustProject:
> +    rust_project: RustProject = {
> +        "crates": generate_crates(
> +            srctree, objtree, sysroot_src, external_src, cfgs, core_edition
> +        ),
> +        "sysroot": str(sysroot),
> +    }
> +
> +    return rust_project
> +
> +def query_ra_version() -> Optional[str]:
> +    try:
> +        # Use the rust-analyzer binary found in $PATH.
> +        ra_version_output = (
> +            subprocess.check_output(
> +                ["rust-analyzer", "--version"],
> +                stdin=subprocess.DEVNULL,
> +            )
> +            .decode("utf-8")
> +            .strip()
> +        )
> +        return ra_version_output
> +    except FileNotFoundError:
> +        logging.warning("Failed to find rust-analyzer in $PATH")
> +        return None
> +
> +def map_ra_version_baseline(ra_version_output: str) -> RaVersionInfo:
> +    baselines = reversed(RaVersionInfo)
> +
> +    version_match = re.search(r"\d+\.\d+\.\d+", ra_version_output)
> +    if version_match:
> +        version_string = version_match.group()
> +        found_version = tuple(map(int, version_string.split(".")))
> +
> +        # `rust-analyzer --version` shows a different version string depending on how the binary
> +        # is built: it may print either the Rust version or the rust-analyzer version itself.
> +        # To distinguish between them, we leverage rust-analyzer's versioning convention.
> +        #
> +        # See:
> +        # - https://github.com/rust-lang/rust-analyzer/blob/fad5c3d2d642/xtask/src/dist.rs#L19-L21
> +        is_ra_version = version_string.startswith(("0.3", "0.4", "0.5"))
> +        if is_ra_version:
> +            for info in baselines:
> +                if found_version >= info.ra_version:
> +                    return info
> +        else:
> +            for info in baselines:
> +                if found_version >= info.rust_version:
> +                    return info
> +
> +    date_match = re.search(r"\d{4}-\d{2}-\d{2}", ra_version_output)
> +    if date_match:
> +        found_date = datetime.strptime(date_match.group(), "%Y-%m-%d")

datetime.strptime throws ValueError on invalid input; perhaps we can
catch that instead of using a regex match.

> +        for info in baselines:
> +            if found_date >= info.release_date:
> +                return info
> +
> +    return RaVersionInfo.MSRV
> +
>  def main() -> None:
>      parser = argparse.ArgumentParser()
>      parser.add_argument('--verbose', '-v', action='store_true')
> @@ -371,10 +516,28 @@ def main() -> None:
>          level=logging.INFO if args.verbose else logging.WARNING
>      )
>
> -    rust_project = {
> -        "crates": generate_crates(args.srctree, args.objtree, args.sysroot_src, args.exttree, args.cfgs, args.core_edition),
> -        "sysroot": str(args.sysroot),
> -    }
> +    ra_version_output = query_ra_version()
> +    if ra_version_output:
> +        compatible_ra_version = map_ra_version_baseline(ra_version_output)
> +    else:
> +        logging.warning(
> +            "Falling back to `rust-project.json` for rust-analyzer %s, %s (shipped with Rust %s)",
> +            ".".join(map(str, RaVersionInfo.MSRV.ra_version)),
> +            datetime.strftime(RaVersionInfo.MSRV.release_date, "%Y-%m-%d"),
> +            ".".join(map(str, RaVersionInfo.MSRV.rust_version)),
> +        )

I think I mentioned this in an earlier review: this warning is logged
under the exact same circumstances as the warning in
`query_ra_version`. It should be one warning, not two.

> +        compatible_ra_version = RaVersionInfo.MSRV
> +
> +    rust_project = generate_rust_project(
> +        compatible_ra_version,
> +        args.srctree,
> +        args.objtree,
> +        args.sysroot,
> +        args.sysroot_src,
> +        args.exttree,
> +        args.cfgs,
> +        args.core_edition,
> +    )
>
>      json.dump(rust_project, sys.stdout, sort_keys=True, indent=4)
>
>
> --
> 2.53.0
>
>