Merge pull request #129 from nushell/do_rest_args

Do rest args
This commit is contained in:
JT 2021-10-12 16:34:21 +13:00 committed by GitHub
commit 60f0394106
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GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 59 additions and 14 deletions

View File

@ -1,4 +1,4 @@
use nu_engine::{eval_block, eval_expression};
use nu_engine::{eval_block, CallExt};
use nu_protocol::ast::Call;
use nu_protocol::engine::{Command, EvaluationContext};
use nu_protocol::{Signature, SyntaxShape, Value};
@ -15,11 +15,14 @@ impl Command for Do {
}
fn signature(&self) -> nu_protocol::Signature {
Signature::build("do").desc(self.usage()).required(
"block",
SyntaxShape::Block(Some(vec![])),
"the block to run",
)
Signature::build("do")
.desc(self.usage())
.required(
"block",
SyntaxShape::Block(Some(vec![])),
"the block to run",
)
.rest("rest", SyntaxShape::Any, "the parameter(s) for the block")
}
fn run(
@ -28,17 +31,54 @@ impl Command for Do {
call: &Call,
input: Value,
) -> Result<nu_protocol::Value, nu_protocol::ShellError> {
let block = &call.positional[0];
let block_id = call.positional[0]
.as_block()
.expect("internal error: expected block");
let rest: Vec<Value> = call.rest(context, 1)?;
let out = eval_expression(context, block)?;
let engine_state = context.engine_state.borrow();
let block = engine_state.get_block(block_id);
match out {
Value::Block { val: block_id, .. } => {
let engine_state = context.engine_state.borrow();
let block = engine_state.get_block(block_id);
eval_block(context, block, input)
let state = context.enter_scope();
let params: Vec<_> = block
.signature
.required_positional
.iter()
.chain(block.signature.optional_positional.iter())
.collect();
for param in params.iter().zip(&rest) {
if let Some(var_id) = param.0.var_id {
state.add_var(var_id, param.1.clone())
}
_ => Ok(Value::nothing()),
}
if let Some(param) = &block.signature.rest_positional {
if rest.len() > params.len() {
let mut rest_items = vec![];
for r in rest.into_iter().skip(params.len()) {
rest_items.push(r);
}
let span = if let Some(rest_item) = rest_items.first() {
rest_item.span()?
} else {
call.head
};
state.add_var(
param
.var_id
.expect("Internal error: rest positional parameter lacks var_id"),
Value::List {
vals: rest_items,
span,
},
)
}
}
eval_block(&state, block, input)
}
}

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@ -722,3 +722,8 @@ fn flag_param_value() -> TestResult {
"155",
)
}
#[test]
fn do_rest_args() -> TestResult {
run_test(r#"(do { |...rest| $rest } 1 2).1 + 10"#, "12")
}