nushell/crates/nu-std/std
JT 9068093081
Improve type hovers (#9515)
# Description

This PR does a few things to help improve type hovers and, in the
process, fixes a few outstanding issues in the type system. Here's a
list of the changes:

* `for` now will try to infer the type of the iteration variable based
on the expression it's given. This fixes things like `for x in [1, 2, 3]
{ }` where `x` now properly gets the int type.
* Removed old input/output type fields from the signature, focuses on
the vec of signatures. Updated a bunch of dataframe commands that hadn't
moved over. This helps tie things together a bit better
* Fixed inference of types from subexpressions to use the last
expression in the block
* Fixed handling of explicit types in `let` and `mut` calls, so we now
respect that as the authoritative type

I also tried to add `def` input/output type inference, but unfortunately
we only know the predecl types universally, which means we won't have
enough information to properly know what the types of the custom
commands are.

# User-Facing Changes

Script typechecking will get tighter in some cases
Hovers should be more accurate in some cases that previously resorted to
any.

# Tests + Formatting
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- `cargo run -- crates/nu-std/tests/run.nu` to run the tests for the
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# After Submitting
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---------

Co-authored-by: Darren Schroeder <343840+fdncred@users.noreply.github.com>
2023-06-29 05:19:48 +12:00
..
assert.nu Logger constants refactored, format argument added, better formatting of failed (non) equality assertions (#9315) 2023-06-04 10:43:40 +02:00
dirs.nu Fix bug in std dirs drop; improve documentation (#9449) 2023-06-16 10:42:50 +02:00
dt.nu Add virtual path abstraction layer (#9245) 2023-05-23 23:48:50 +03:00
help.nu split $nu variable into scope commands and simpler $nu (#9487) 2023-06-21 09:33:01 +12:00
iter.nu Add zip-into-record to std iter (#9395) 2023-06-10 20:15:30 +02:00
log.nu Logger constants refactored, format argument added, better formatting of failed (non) equality assertions (#9315) 2023-06-04 10:43:40 +02:00
mod.nu std: refactor test-runner to no longer require tests to be exported (#9355) 2023-06-10 20:16:17 +02:00
testing.nu std: refactor test-runner to no longer require tests to be exported (#9355) 2023-06-10 20:16:17 +02:00
xml.nu Improve type hovers (#9515) 2023-06-29 05:19:48 +12:00