Fixes#14145
# User-Facing Changes
An empty rest match would be `null` previously. Now it will be an empty
list.
This is a breaking change for any scripts relying on the old behavior.
Example script:
```nu
match [1] {
[_ ..$rest] => {
match $rest {
null => { "old" }
[] => { "new" }
}
}
}
```
This expression would evaluate to "old" on current nu versions and "new"
with this patch.
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# Description
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Fix#9878
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
Writing comments in match blocks will be allowed.
# Tests + Formatting
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crates/nu-std"` to run the tests for the standard library
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# Description
Support pattern matching against the `null` literal. Fixes#10799
### Before
```nushell
> match null { null => "success", _ => "failure" }
failure
```
### After
```nushell
> match null { null => "success", _ => "failure" }
success
```
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
Users can pattern match against a `null` literal.
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# Description
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This PR is related to **Tests: clean up unnecessary use of cwd,
pipeline(), etc.
[#8670](https://github.com/nushell/nushell/issues/8670)**
- Removed the `r#"..."#` raw string literal syntax, which is unnecessary
when there are no special characters that need quoting from the tests
that use the `nu!` macro.
- `cwd:` and `pipeline()` has not changed
# User-Facing Changes
<!-- List of all changes that impact the user experience here. This
helps us keep track of breaking changes. -->
# Tests + Formatting
<!--
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect -A clippy::result_large_err` to check that
you're using the standard code style
- `cargo test --workspace` to check that all tests pass
- `cargo run -- -c "use std testing; testing run-tests --path
crates/nu-std"` to run the tests for the standard library
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
-->
# After Submitting
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# Description
The working directory doesn't have to be set for those tests (or would
be the default anyways). When appropriate also remove calls to the
`pipeline()` function. In most places kept the diff minimal and only
removed the superfluous part to not pollute the blame view. With simpler
tests also simplified things to make them more readable overall (this
included removal of the raw string literal).
Work for #8670
## description
this pr adds [match
guards](https://doc.rust-lang.org/reference/expressions/match-expr.html#match-guards)
to match patterns
```nushell
match $x {
_ if $x starts-with 'nu' => {},
$x => {}
}
```
these work pretty much like rust's match guards, with few limitations:
1. multiple matches using the `|` are not (yet?) supported
```nushell
match $num {
0 | _ if (is-odd $num) => {},
_ => {}
}
```
2. blocks cannot be used as guards, (yet?)
```nushell
match $num {
$x if { $x ** $x == inf } => {},
_ => {}
}
```
## checklist
- [x] syntax
- [x] syntax highlighting[^1]
- [x] semantics
- [x] tests
- [x] clean up
[^1]: defered for another pr
# Description
Adds two more patterns when working with lists:
```
[1, ..$remainder]
```
and
```
[1, ..]
```
The first one collects the remaining items and assigns them into the
variable. The second one ignores any remaining values.
# User-Facing Changes
Adds more capability to list pattern matching.
# Tests + Formatting
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect` to check that you're using the standard code
style
- `cargo test --workspace` to check that all tests pass
- `cargo run -- crates/nu-utils/standard_library/tests.nu` to run the
tests for the standard library
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
# After Submitting
If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
# Description
Adds `|` patterns to `match`, allowing you to try multiple patterns for
the same case.
Example:
```
match {b: 1} { {a: $b} | {b: $b} => { print $b } }
```
Variables that don't bind are set to `$nothing` so that they can be
later checked.
This PR also:
fixes#8631
Creates a set of integration tests for pattern matching also
# User-Facing Changes
Adds `|` to `match`. Fixes variable binding scope.
# Tests + Formatting
Don't forget to add tests that cover your changes.
Make sure you've run and fixed any issues with these commands:
- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect` to check that you're using the standard code
style
- `cargo test --workspace` to check that all tests pass
> **Note**
> from `nushell` you can also use the `toolkit` as follows
> ```bash
> use toolkit.nu # or use an `env_change` hook to activate it
automatically
> toolkit check pr
> ```
# After Submitting
If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.
