mirror of
https://github.com/nushell/nushell.git
synced 2025-05-28 14:07:08 +02:00
# Description When implementing a `Command`, one must also import all the types present in the function signatures for `Command`. This makes it so that we often import the same set of types in each command implementation file. E.g., something like this: ```rust use nu_protocol::ast::Call; use nu_protocol::engine::{Command, EngineState, Stack}; use nu_protocol::{ record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError, Signature, Span, Type, Value, }; ``` This PR adds the `nu_engine::command_prelude` module which contains the necessary and commonly used types to implement a `Command`: ```rust // command_prelude.rs pub use crate::CallExt; pub use nu_protocol::{ ast::{Call, CellPath}, engine::{Command, EngineState, Stack}, record, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, IntoSpanned, PipelineData, Record, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value, }; ``` This should reduce the boilerplate needed to implement a command and also gives us a place to track the breadth of the `Command` API. I tried to be conservative with what went into the prelude modules, since it might be hard/annoying to remove items from the prelude in the future. Let me know if something should be included or excluded.
196 lines
8.9 KiB
Rust
196 lines
8.9 KiB
Rust
use nu_engine::command_prelude::*;
|
|
|
|
use std::fmt::Write;
|
|
|
|
#[derive(Clone)]
|
|
pub struct ViewSource;
|
|
|
|
impl Command for ViewSource {
|
|
fn name(&self) -> &str {
|
|
"view source"
|
|
}
|
|
|
|
fn usage(&self) -> &str {
|
|
"View a block, module, or a definition."
|
|
}
|
|
|
|
fn signature(&self) -> nu_protocol::Signature {
|
|
Signature::build("view source")
|
|
.input_output_types(vec![(Type::Nothing, Type::String)])
|
|
.required("item", SyntaxShape::Any, "Name or block to view.")
|
|
.category(Category::Debug)
|
|
}
|
|
|
|
fn run(
|
|
&self,
|
|
engine_state: &EngineState,
|
|
stack: &mut Stack,
|
|
call: &Call,
|
|
_input: PipelineData,
|
|
) -> Result<PipelineData, ShellError> {
|
|
let arg: Value = call.req(engine_state, stack, 0)?;
|
|
let arg_span = arg.span();
|
|
|
|
match arg {
|
|
Value::String { val, .. } => {
|
|
if let Some(decl_id) = engine_state.find_decl(val.as_bytes(), &[]) {
|
|
// arg is a command
|
|
let decl = engine_state.get_decl(decl_id);
|
|
let sig = decl.signature();
|
|
let vec_of_required = &sig.required_positional;
|
|
let vec_of_optional = &sig.optional_positional;
|
|
let rest = &sig.rest_positional;
|
|
let vec_of_flags = &sig.named;
|
|
|
|
if decl.is_alias() {
|
|
if let Some(alias) = &decl.as_alias() {
|
|
let contents = String::from_utf8_lossy(
|
|
engine_state.get_span_contents(alias.wrapped_call.span),
|
|
);
|
|
Ok(Value::string(contents, call.head).into_pipeline_data())
|
|
} else {
|
|
Ok(Value::string("no alias found", call.head).into_pipeline_data())
|
|
}
|
|
}
|
|
// gets vector of positionals.
|
|
else if let Some(block_id) = decl.get_block_id() {
|
|
let block = engine_state.get_block(block_id);
|
|
if let Some(block_span) = block.span {
|
|
let contents = engine_state.get_span_contents(block_span);
|
|
// name of function
|
|
let mut final_contents = format!("def {val} [ ");
|
|
for n in vec_of_required {
|
|
let _ = write!(&mut final_contents, "{}: {} ", n.name, n.shape);
|
|
// positional argu,emts
|
|
}
|
|
for n in vec_of_optional {
|
|
let _ = write!(&mut final_contents, "{}?: {} ", n.name, n.shape);
|
|
}
|
|
for n in vec_of_flags {
|
|
// skip adding the help flag
|
|
if n.long == "help" {
|
|
continue;
|
|
}
|
|
let _ = write!(&mut final_contents, "--{}", n.long);
|
|
if let Some(short) = n.short {
|
|
let _ = write!(&mut final_contents, "(-{})", short);
|
|
}
|
|
if let Some(arg) = &n.arg {
|
|
let _ = write!(&mut final_contents, ": {}", arg);
|
|
}
|
|
final_contents.push(' ');
|
|
}
|
|
if let Some(rest_arg) = rest {
|
|
let _ = write!(
|
|
&mut final_contents,
|
|
"...{}:{}",
|
|
rest_arg.name, rest_arg.shape
|
|
);
|
|
}
|
|
final_contents.push_str("] ");
|
|
final_contents.push_str(&String::from_utf8_lossy(contents));
|
|
Ok(Value::string(final_contents, call.head).into_pipeline_data())
|
|
} else {
|
|
Err(ShellError::GenericError {
|
|
error: "Cannot view value".to_string(),
|
|
msg: "the command does not have a viewable block span".to_string(),
|
|
span: Some(arg_span),
|
|
help: None,
|
|
inner: vec![],
|
|
})
|
|
}
|
|
} else {
|
|
Err(ShellError::GenericError {
|
|
error: "Cannot view value".to_string(),
|
|
msg: "the command does not have a viewable block".to_string(),
|
|
span: Some(arg_span),
|
|
help: None,
|
|
inner: vec![],
|
|
})
|
|
}
|
|
} else if let Some(module_id) = engine_state.find_module(val.as_bytes(), &[]) {
|
|
// arg is a module
|
|
let module = engine_state.get_module(module_id);
|
|
if let Some(module_span) = module.span {
|
|
let contents = engine_state.get_span_contents(module_span);
|
|
Ok(Value::string(String::from_utf8_lossy(contents), call.head)
|
|
.into_pipeline_data())
|
|
} else {
|
|
Err(ShellError::GenericError {
|
|
error: "Cannot view value".to_string(),
|
|
msg: "the module does not have a viewable block".to_string(),
|
|
span: Some(arg_span),
|
|
help: None,
|
|
inner: vec![],
|
|
})
|
|
}
|
|
} else {
|
|
Err(ShellError::GenericError {
|
|
error: "Cannot view value".to_string(),
|
|
msg: "this name does not correspond to a viewable value".to_string(),
|
|
span: Some(arg_span),
|
|
help: None,
|
|
inner: vec![],
|
|
})
|
|
}
|
|
}
|
|
value => {
|
|
if let Ok(block_id) = value.coerce_block() {
|
|
let block = engine_state.get_block(block_id);
|
|
|
|
if let Some(span) = block.span {
|
|
let contents = engine_state.get_span_contents(span);
|
|
Ok(Value::string(String::from_utf8_lossy(contents), call.head)
|
|
.into_pipeline_data())
|
|
} else {
|
|
Ok(Value::string("<internal command>", call.head).into_pipeline_data())
|
|
}
|
|
} else {
|
|
Err(ShellError::GenericError {
|
|
error: "Cannot view value".to_string(),
|
|
msg: "this value cannot be viewed".to_string(),
|
|
span: Some(arg_span),
|
|
help: None,
|
|
inner: vec![],
|
|
})
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn examples(&self) -> Vec<Example> {
|
|
vec![
|
|
Example {
|
|
description: "View the source of a code block",
|
|
example: r#"let abc = {|| echo 'hi' }; view source $abc"#,
|
|
result: Some(Value::test_string("{|| echo 'hi' }")),
|
|
},
|
|
Example {
|
|
description: "View the source of a custom command",
|
|
example: r#"def hi [] { echo 'Hi!' }; view source hi"#,
|
|
result: Some(Value::test_string("def hi [] { echo 'Hi!' }")),
|
|
},
|
|
Example {
|
|
description: "View the source of a custom command, which participates in the caller environment",
|
|
example: r#"def --env foo [] { $env.BAR = 'BAZ' }; view source foo"#,
|
|
result: Some(Value::test_string("def foo [] { $env.BAR = 'BAZ' }")),
|
|
},
|
|
Example {
|
|
description: "View the source of a custom command with flags and arguments",
|
|
example: r#"def test [a?:any --b:int ...rest:string] { echo 'test' }; view source test"#,
|
|
result: Some(Value::test_string("def test [ a?: any --b: int ...rest: string] { echo 'test' }")),
|
|
},
|
|
Example {
|
|
description: "View the source of a module",
|
|
example: r#"module mod-foo { export-env { $env.FOO_ENV = 'BAZ' } }; view source mod-foo"#,
|
|
result: Some(Value::test_string(" export-env { $env.FOO_ENV = 'BAZ' }")),
|
|
},
|
|
Example {
|
|
description: "View the source of an alias",
|
|
example: r#"alias hello = echo hi; view source hello"#,
|
|
result: Some(Value::test_string("echo hi")),
|
|
},
|
|
]
|
|
}
|
|
}
|