Fix overlay_use_main_not_exported hanging when an external spam command exists

[nibon7]

Description

The spam command is provided by opensp which causes overlay_use_main_not_exported to hang. opensp is pulled by gnome-control-center on my system.

opensp package list

opensp 1.5.2-10 File List

Package has 224 files and 14 directories.

[Back to Package](https://archlinux.org/packages/extra/x86_64/opensp/)

    usr/
    usr/bin/
    usr/bin/nsgmls
    usr/bin/onsgmls
    usr/bin/osgmlnorm
    usr/bin/ospam
    usr/bin/ospcat
    usr/bin/ospent
    usr/bin/osx
    usr/bin/sgml2xml
    usr/bin/sgmlnorm
    usr/bin/spam
    ...snip...

cargo test output

...snip...
test shell::pipeline::commands::internal::unlet_variable_in_parent_scope ... ok
test shell::pipeline::commands::internal::unlet_env_variable ... ok
test shell::pipeline::doesnt_break_on_utf8 ... ok
test shell::run_export_extern ... ok
test shell::run_script_that_looks_like_module ... ok
test shell::pipeline::commands::internal::can_process_one_row_from_internal_and_pipes_it_to_stdin_of_external ... ok
test shell::pipeline::commands::internal::variable_scoping::access_variables_in_scopes ... ok
test shell::run_in_login_mode ... ok
test shell::run_in_interactive_mode ... ok
test shell::run_in_noninteractive_mode ... ok
test shell::run_in_not_login_mode ... ok
test shell::pipeline::commands::internal::subexpression_properly_redirects ... ok
test shell::pipeline::commands::internal::subexpression_handles_dot ... ok
test shell::pipeline::commands::internal::takes_rows_of_nu_value_strings_and_pipes_it_to_stdin_of_external ... ok
test overlays::overlay_use_main_not_exported has been running for over 60 seconds

User-Facing Changes

N/A

Tests + Formatting

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 to check that you're using the standard code style
• cargo test --workspace to check that all tests pass (on Windows make sure to enable developer mode)
• cargo run -- -c "use std testing; testing run-tests --path crates/nu-std" to run the tests for the standard library

After Submitting

N/A

[fdncred]

That's hilarious that a spam command exists. I'm not sure foo is super unique either though. We can run with it for now though.

/cc @kubouch - just because it's funny.

[kubouch]

I bet someone will have a foo command and submits a PR that changes it back to spam.

[fdncred]

LOL, we could make it foospam or something more unique?

[sholderbach]

We need to figure out how to properly purge the environment including $env.PATH before running tests without bricking windows execution.

See the discussion in:

• Tests that depend on executables in host PATH can break #8463
• test: clear parent envs to prevent leakage to tests #9976 (comment)
• std::process::Command::env_clear is unusable on Windows rust-lang/rust#114737

[nibon7]

I bet someone will have a foo command and submits a PR that changes it back to spam.

foo has been used :)

nushell/tests/overlays/mod.rs

Lines 6 to 19 in 94b2726

	#[test]
	fn add_overlay() {
	let inp = &[
	r#"module spam { export def foo [] { "foo" } }"#,
	"overlay use spam",
	"foo",
	];
	let actual = nu!(&inp.join("; "));
	let actual_repl = nu!(nu_repl_code(inp));
	assert_eq!(actual.out, "foo");
	assert_eq!(actual_repl.out, "foo");
	}