Stefan Holderbach 95b78eee25
Change the usage misnomer to "description" (#13598)
# Description
    
The meaning of the word usage is specific to describing how a command
function is *used* and not a synonym for general description. Usage can
be used to describe the SYNOPSIS or EXAMPLES sections of a man page
where the permitted argument combinations are shown or example *uses*
are given.
Let's not confuse people and call it what it is a description.

Our `help` command already creates its own *Usage* section based on the
available arguments and doesn't refer to the description with usage.

# User-Facing Changes

`help commands` and `scope commands` will now use `description` or
`extra_description`
`usage`-> `description`
`extra_usage` -> `extra_description`

Breaking change in the plugin protocol:

In the signature record communicated with the engine.
`usage`-> `description`
`extra_usage` -> `extra_description`

The same rename also takes place for the methods on
`SimplePluginCommand` and `PluginCommand`

# Tests + Formatting
- Updated plugin protocol specific changes
# After Submitting
- [ ] update plugin protocol doc
2024-08-22 12:02:08 +02:00

68 lines
2.2 KiB
Rust

use nu_engine::command_prelude::*;
use nu_protocol::engine::CommandType;
#[derive(Clone)]
pub struct Module;
impl Command for Module {
fn name(&self) -> &str {
"module"
}
fn description(&self) -> &str {
"Define a custom module."
}
fn signature(&self) -> nu_protocol::Signature {
Signature::build("module")
.input_output_types(vec![(Type::Nothing, Type::Nothing)])
.allow_variants_without_examples(true)
.required("module", SyntaxShape::String, "Module name or module path.")
.optional(
"block",
SyntaxShape::Block,
"Body of the module if 'module' parameter is not a module path.",
)
.category(Category::Core)
}
fn extra_description(&self) -> &str {
r#"This command is a parser keyword. For details, check:
https://www.nushell.sh/book/thinking_in_nu.html"#
}
fn command_type(&self) -> CommandType {
CommandType::Keyword
}
fn run(
&self,
_engine_state: &EngineState,
_stack: &mut Stack,
_call: &Call,
_input: PipelineData,
) -> Result<PipelineData, ShellError> {
Ok(PipelineData::empty())
}
fn examples(&self) -> Vec<Example> {
vec![
Example {
description: "Define a custom command in a module and call it",
example: r#"module spam { export def foo [] { "foo" } }; use spam foo; foo"#,
result: Some(Value::test_string("foo")),
},
Example {
description: "Define an environment variable in a module",
example: r#"module foo { export-env { $env.FOO = "BAZ" } }; use foo; $env.FOO"#,
result: Some(Value::test_string("BAZ")),
},
Example {
description: "Define a custom command that participates in the environment in a module and call it",
example: r#"module foo { export def --env bar [] { $env.FOO_BAR = "BAZ" } }; use foo bar; bar; $env.FOO_BAR"#,
result: Some(Value::test_string("BAZ")),
},
]
}
}