Disable alias recursion (#8397)

# Description

Prevents alias from aliasing itself. It allows a commonly requested
pattern similar to `alias ls = ls -l`.

One small issue is that the syntax highlighting is a bit off:

![alias_itself_no_color](https://user-images.githubusercontent.com/25571562/224545129-8a3ff535-347b-4a4e-b686-11493bb2a33b.png)

Fixes https://github.com/nushell/nushell/issues/8246

# User-Facing Changes

Shouldn't be a breaking change.

# 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

# 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.
This commit is contained in:
Jakub Žádník 2023-03-12 19:16:26 +02:00 committed by GitHub
parent a52386e837
commit 808e523adc
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 35 additions and 0 deletions

View File

@ -90,3 +90,23 @@ fn cant_alias_keyword() {
));
assert!(actual.err.contains("cant_alias_keyword"));
}
#[test]
fn alias_wont_recurse() {
let actual = nu!(
cwd: ".", pipeline(
r#"
module myspamsymbol {
export def myfoosymbol [prefix: string, msg: string] {
$prefix + $msg
}
};
use myspamsymbol myfoosymbol;
alias myfoosymbol = myfoosymbol 'hello';
myfoosymbol ' world'
"#
));
assert_eq!(actual.out, "hello world");
assert!(actual.err.is_empty());
}

View File

@ -804,6 +804,13 @@ pub fn parse_alias(
let replacement_spans = &spans[(split_id + 2)..];
// Temporarily hide the alias itself to prevent recursion
let predecl_id = working_set
.delta
.last_scope_frame_mut()
.predecls
.remove(&alias_name);
let (expr, err) = parse_call(
working_set,
replacement_spans,
@ -812,6 +819,14 @@ pub fn parse_alias(
false, // TODO: Should this be set properly???
);
if let Some(id) = predecl_id {
working_set
.delta
.last_scope_frame_mut()
.predecls
.insert(alias_name.to_vec(), id);
}
if let Some(e) = err {
if let ParseError::MissingPositional(..) = e {
// ignore missing required positional