Relax indexmap dependency

[gnaaman-dn]

Halloo,

Noticed some version resolve errors when trying to use the indexmap features.

❯ cargo add pyo3 --features indexmap
❯ cargo add serde_yaml
    Updating crates.io index
      Adding serde_yaml v0.9.16 to dependencies.
error: failed to select a version for `indexmap`.
    ... required by package `pyo3 v0.17.3`
    ... which satisfies dependency `pyo3 = "^0.17.3"` of package `pyo3-indexmap v0.1.0 (/home/dn/repos/pyo3-indexmap)`
versions that meet the requirements `>=1.6, <1.8` are: 1.7.0, 1.6.2, 1.6.1, 1.6.0

all possible versions conflict with previously selected packages.

  previously selected package `indexmap v1.9.0`
    ... which satisfies dependency `indexmap = "^1.9"` of package `serde_yaml v0.9.16`
    ... which satisfies dependency `serde_yaml = "^0.9.16"` of package `pyo3-indexmap v0.1.0 (/home/dn/repos/pyo3-indexmap)`

failed to select a version for `indexmap` which could resolve this conflict

Couldn't find a specific reason for this limitation so I tried upgrading the dependency and running the tests.
Ran the tests locally with indexmap==v1.9.2:

❯ cargo test --features indexmap conversions::indexmap
...
running 4 tests
test conversions::indexmap::test_indexmap::test_indexmap_indexmap_insertion_order_round_trip ... ok
test conversions::indexmap::test_indexmap::test_indexmap_indexmap_to_python ... ok
test conversions::indexmap::test_indexmap::test_indexmap_indexmap_into_python ... ok
test conversions::indexmap::test_indexmap::test_indexmap_indexmap_into_dict ... ok

test result: ok. 4 passed; 0 failed; 0 ignored; 0 measured; 536 filtered out; finished in 0.03s

(Tried running cargo xtask ci but it failed on some warnings in the generated FFI code)

This relaxes the restrictions on indexmap so that the latest version is also supported,
hope that's okay.

Cheers,
Gilad

[adamreichold]

As the CI indicates, this does indeed need a news fragment describing the change, c.f. https://github.com/PyO3/pyo3/blob/main/Contributing.md#documenting-changes.

[adamreichold]

bors r+

[bors]

Build succeeded!

And happy new year! 🎉

• conclusion