Cannot build with "dtype-categorical" enabled

[besselfunct]

Checks

• I have checked that this issue has not already been reported.
• I have confirmed this bug exists on the latest version of Polars.

Reproducible example

[dependencies]
polars = {version = "0.43.1", features = ["dtype-categorical"]}

Log output

error[E0599]: no method named `raw_table_mut` found for struct `hashbrown::HashMap` in the current scope
   --> /home/besselfunct/.cargo/registry/src/index.crates.io-6f17d22bba15001f/polars-core-0.43.1/src/chunked_array/builder/list/categorical.rs:145:33
    |
145 |                 self.idx_lookup.raw_table_mut().find_or_find_insert_slot(
    |                                 ^^^^^^^^^^^^^ method not found in `HashMap<KeyWrapper, (), RandomState>`

error[E0599]: no method named `raw_table_mut` found for struct `hashbrown::HashMap` in the current scope
   --> /home/besselfunct/.cargo/registry/src/index.crates.io-6f17d22bba15001f/polars-core-0.43.1/src/chunked_array/builder/list/categorical.rs:164:41
    |
164 |                         self.idx_lookup.raw_table_mut().insert_in_slot(
    |                                         ^^^^^^^^^^^^^ method not found in `HashMap<KeyWrapper, (), RandomState>`

error[E0599]: no method named `raw_table_mut` found for struct `hashbrown::HashMap` in the current scope
  --> /home/besselfunct/.cargo/registry/src/index.crates.io-6f17d22bba15001f/polars-core-0.43.1/src/chunked_array/logical/categorical/builder.rs:43:32
   |
43 |             self.local_mapping.raw_table_mut().find_or_find_insert_slot(
   |                                ^^^^^^^^^^^^^ method not found in `HashMap<KeyWrapper, (), RandomState>`

error[E0599]: no method named `raw_table_mut` found for struct `hashbrown::HashMap` in the current scope
  --> /home/besselfunct/.cargo/registry/src/index.crates.io-6f17d22bba15001f/polars-core-0.43.1/src/chunked_array/logical/categorical/builder.rs:63:26
   |
62 | /                     self.local_mapping
63 | |                         .raw_table_mut()
   | |                         -^^^^^^^^^^^^^ method not found in `HashMap<KeyWrapper, (), RandomState>`
   | |_________________________|
   |

For more information about this error, try `rustc --explain E0599`.
error: could not compile `polars-core` (lib) due to 4 previous errors

Issue description

Trying to recreate this example from the user guide when I ran into this issue.

Expected behavior

polars-core should build a MWE with the dtype-categorical flag enabled.

Installed versions

dtype-categorical

[Shoeboxam]

Hashbrown just updated to 0.15, with the following section in the changelog:
https://github.com/rust-lang/hashbrown/blob/HEAD/CHANGELOG.md#removed

Polars takes a workspace dependency on hashbrown "0.14", which, by cargo's caret comparison rules, allows the minor version to vary to 0.15 where the API has changed. If Polars took a hashbrown dependency of "0.14.0", then only the patch version would be allowed to vary.

I got things working again by downgrading indexmap in the cargo.lock:

cargo update indexmap@2.6.0 --precise 2.5.0

[besselfunct]

I apologize, I'm somewhat of a novice when it comes to cargo. I ran the command you suggested, and now I can build, but it looks like my Cargo.toml didn't change. Is there a way to include this information in the Cargo.toml so that it can be explicitly declared?

[Shoeboxam]

I'm not aware of a way to do so via the Cargo.toml.

I'm also observing that my fix above doesn't always work-- cargo somehow still pulls down hashbrown 0.15 when building on other platforms/with cibuildwheel, and I can't seem to control it.

[Bidek56]

I am having the same errors compiling nodejs-polars, does it mean I need to wait for the next release of polars-rs? Thx

[cuviper]

Polars is using .raw_table_mut(), so it should explicitly enable hashbrown's "raw" feature.
See also: #19076 (comment)

Yes, indexmap 2.6.0 updated to hashbrown 0.15, but polars will still be using its own hashbrown 0.14.

[Shoeboxam]

Thanks, to recap, the temporary Cargo.toml fix, until the Polars crate is updated, is to add the following line to your dependencies:

hashbrown = { version = "=0.14.5", features = ["raw"] }

[cuviper]

The precise "=0.14.5" pinning shouldn't be necessary, but that's likely to be the last 0.14 release anyway. The important part is to add the "raw" feature.