sdf-jkl opened a new issue, #10102:
URL: https://github.com/apache/arrow-rs/issues/10102

   **Is your feature request related to a problem or challenge? Please describe 
what you are trying to do.**
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   This is part of #8982 which wants to support the temporal types 
(`Timestamp*` incl. NTZ + timezone, `Date32`/`Date64`, `Time32*`/`Time64*`).
   
   Currently the temporal cast logic in `parquet-variant-compute` 
(`type_conversion.rs`) hand-rolls conversion/truncation logic that *mimics* 
`arrow-cast` rather than reusing it. For example, several `Time*`/`Timestamp*` 
impls return `None` when there is leftover sub-second precision instead of 
truncating the way `arrow-cast` does (`lossy` is the default in the cast 
kernel).
   
   **Describe the solution you'd like**
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   Align the logic of casting from/to the temporal types in `parquet-variant` 
with `arrow-cast` by reusing `arrow-cast`'s scalar conversion primitives (the 
same approach #9688 took for decimals, where `rescale_decimal` / 
`parse_string_to_decimal_native` / `single_float_to_decimal` were exposed and 
reused) instead of re-implementing the logic. This keeps a single source of 
truth for the cast semantics and lets the perfect-shredding fast path 
(`can_use_perfect_shredding_arrow_cast`, added in #9862) be widened to cover 
the truncating temporal pairs it currently excludes.
   
   **Describe alternatives you've considered**
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   **Additional context**
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   cc @klion26 @AdamGS


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