nushell/crates/nu-plugin-protocol/src/evaluated_call.rs
Devyn Cairns d618fd0527
Fix bad method links in docstrings (#13471)
# Description

Seems like I developed a bit of a bad habit of trying to link

```rust
/// [`.foo()`]
```

in docstrings, and this just doesn't work automatically; you have to do 

```rust
/// [`.foo()`](Self::foo)
```

if you want it to actually link. I think I found and replaced all of
these.

# User-Facing Changes

Just docs.
2024-07-27 19:39:29 -07:00

533 lines
18 KiB
Rust

use nu_protocol::{
ast::{self, Expression},
engine::{Call, CallImpl, EngineState, Stack},
ir, FromValue, ShellError, Span, Spanned, Value,
};
use serde::{Deserialize, Serialize};
/// A representation of the plugin's invocation command including command line args
///
/// The `EvaluatedCall` contains information about the way a `Plugin` was invoked representing the
/// [`Span`] corresponding to the invocation as well as the arguments it was invoked with. It is
/// one of the items passed to `PluginCommand::run()`, along with the plugin reference, the engine
/// interface, and a [`Value`] that represents the input.
///
/// The evaluated call is used with the Plugins because the plugin doesn't have
/// access to the Stack and the EngineState the way a built in command might. For that
/// reason, before encoding the message to the plugin all the arguments to the original
/// call (which are expressions) are evaluated and passed to Values
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct EvaluatedCall {
/// Span of the command invocation
pub head: Span,
/// Values of positional arguments
pub positional: Vec<Value>,
/// Names and values of named arguments
pub named: Vec<(Spanned<String>, Option<Value>)>,
}
impl EvaluatedCall {
/// Create a new [`EvaluatedCall`] with the given head span.
pub fn new(head: Span) -> EvaluatedCall {
EvaluatedCall {
head,
positional: vec![],
named: vec![],
}
}
/// Add a positional argument to an [`EvaluatedCall`].
///
/// # Example
///
/// ```rust
/// # use nu_protocol::{Value, Span, IntoSpanned};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let head = Span::test_data();
/// let mut call = EvaluatedCall::new(head);
/// call.add_positional(Value::test_int(1337));
/// ```
pub fn add_positional(&mut self, value: Value) -> &mut Self {
self.positional.push(value);
self
}
/// Add a named argument to an [`EvaluatedCall`].
///
/// # Example
///
/// ```rust
/// # use nu_protocol::{Value, Span, IntoSpanned};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let head = Span::test_data();
/// let mut call = EvaluatedCall::new(head);
/// call.add_named("foo".into_spanned(head), Value::test_string("bar"));
/// ```
pub fn add_named(&mut self, name: Spanned<impl Into<String>>, value: Value) -> &mut Self {
self.named.push((name.map(Into::into), Some(value)));
self
}
/// Add a flag argument to an [`EvaluatedCall`]. A flag argument is a named argument with no
/// value.
///
/// # Example
///
/// ```rust
/// # use nu_protocol::{Value, Span, IntoSpanned};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let head = Span::test_data();
/// let mut call = EvaluatedCall::new(head);
/// call.add_flag("pretty".into_spanned(head));
/// ```
pub fn add_flag(&mut self, name: Spanned<impl Into<String>>) -> &mut Self {
self.named.push((name.map(Into::into), None));
self
}
/// Builder variant of [`.add_positional()`](Self::add_positional).
pub fn with_positional(mut self, value: Value) -> Self {
self.add_positional(value);
self
}
/// Builder variant of [`.add_named()`](Self::add_named).
pub fn with_named(mut self, name: Spanned<impl Into<String>>, value: Value) -> Self {
self.add_named(name, value);
self
}
/// Builder variant of [`.add_flag()`](Self::add_flag).
pub fn with_flag(mut self, name: Spanned<impl Into<String>>) -> Self {
self.add_flag(name);
self
}
/// Try to create an [`EvaluatedCall`] from a command `Call`.
pub fn try_from_call(
call: &Call,
engine_state: &EngineState,
stack: &mut Stack,
eval_expression_fn: fn(&EngineState, &mut Stack, &Expression) -> Result<Value, ShellError>,
) -> Result<Self, ShellError> {
match &call.inner {
CallImpl::AstRef(call) => {
Self::try_from_ast_call(call, engine_state, stack, eval_expression_fn)
}
CallImpl::AstBox(call) => {
Self::try_from_ast_call(call, engine_state, stack, eval_expression_fn)
}
CallImpl::IrRef(call) => Self::try_from_ir_call(call, stack),
CallImpl::IrBox(call) => Self::try_from_ir_call(call, stack),
}
}
fn try_from_ast_call(
call: &ast::Call,
engine_state: &EngineState,
stack: &mut Stack,
eval_expression_fn: fn(&EngineState, &mut Stack, &Expression) -> Result<Value, ShellError>,
) -> Result<Self, ShellError> {
let positional =
call.rest_iter_flattened(0, |expr| eval_expression_fn(engine_state, stack, expr))?;
let mut named = Vec::with_capacity(call.named_len());
for (string, _, expr) in call.named_iter() {
let value = match expr {
None => None,
Some(expr) => Some(eval_expression_fn(engine_state, stack, expr)?),
};
named.push((string.clone(), value))
}
Ok(Self {
head: call.head,
positional,
named,
})
}
fn try_from_ir_call(call: &ir::Call, stack: &Stack) -> Result<Self, ShellError> {
let positional = call.rest_iter_flattened(stack, 0)?;
let mut named = Vec::with_capacity(call.named_len(stack));
named.extend(
call.named_iter(stack)
.map(|(name, value)| (name.map(|s| s.to_owned()), value.cloned())),
);
Ok(Self {
head: call.head,
positional,
named,
})
}
/// Check if a flag (named parameter that does not take a value) is set
/// Returns Ok(true) if flag is set or passed true value
/// Returns Ok(false) if flag is not set or passed false value
/// Returns Err if passed value is not a boolean
///
/// # Examples
/// Invoked as `my_command --foo`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: Vec::new(),
/// # named: vec![(
/// # Spanned { item: "foo".to_owned(), span: null_span},
/// # None
/// # )],
/// # };
/// assert!(call.has_flag("foo").unwrap());
/// ```
///
/// Invoked as `my_command --bar`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: Vec::new(),
/// # named: vec![(
/// # Spanned { item: "bar".to_owned(), span: null_span},
/// # None
/// # )],
/// # };
/// assert!(!call.has_flag("foo").unwrap());
/// ```
///
/// Invoked as `my_command --foo=true`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: Vec::new(),
/// # named: vec![(
/// # Spanned { item: "foo".to_owned(), span: null_span},
/// # Some(Value::bool(true, Span::unknown()))
/// # )],
/// # };
/// assert!(call.has_flag("foo").unwrap());
/// ```
///
/// Invoked as `my_command --foo=false`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: Vec::new(),
/// # named: vec![(
/// # Spanned { item: "foo".to_owned(), span: null_span},
/// # Some(Value::bool(false, Span::unknown()))
/// # )],
/// # };
/// assert!(!call.has_flag("foo").unwrap());
/// ```
///
/// Invoked with wrong type as `my_command --foo=1`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: Vec::new(),
/// # named: vec![(
/// # Spanned { item: "foo".to_owned(), span: null_span},
/// # Some(Value::int(1, Span::unknown()))
/// # )],
/// # };
/// assert!(call.has_flag("foo").is_err());
/// ```
pub fn has_flag(&self, flag_name: &str) -> Result<bool, ShellError> {
for name in &self.named {
if flag_name == name.0.item {
return match &name.1 {
Some(Value::Bool { val, .. }) => Ok(*val),
None => Ok(true),
Some(result) => Err(ShellError::CantConvert {
to_type: "bool".into(),
from_type: result.get_type().to_string(),
span: result.span(),
help: Some("".into()),
}),
};
}
}
Ok(false)
}
/// Returns the [`Span`] of the name of an optional named argument.
///
/// This can be used in errors for named arguments that don't take values.
pub fn get_flag_span(&self, flag_name: &str) -> Option<Span> {
self.named
.iter()
.find(|(name, _)| name.item == flag_name)
.map(|(name, _)| name.span)
}
/// Returns the [`Value`] of an optional named argument
///
/// # Examples
/// Invoked as `my_command --foo 123`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: Vec::new(),
/// # named: vec![(
/// # Spanned { item: "foo".to_owned(), span: null_span},
/// # Some(Value::int(123, null_span))
/// # )],
/// # };
/// let opt_foo = match call.get_flag_value("foo") {
/// Some(Value::Int { val, .. }) => Some(val),
/// None => None,
/// _ => panic!(),
/// };
/// assert_eq!(opt_foo, Some(123));
/// ```
///
/// Invoked as `my_command`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: Vec::new(),
/// # named: vec![],
/// # };
/// let opt_foo = match call.get_flag_value("foo") {
/// Some(Value::Int { val, .. }) => Some(val),
/// None => None,
/// _ => panic!(),
/// };
/// assert_eq!(opt_foo, None);
/// ```
pub fn get_flag_value(&self, flag_name: &str) -> Option<Value> {
for name in &self.named {
if flag_name == name.0.item {
return name.1.clone();
}
}
None
}
/// Returns the [`Value`] of a given (zero indexed) positional argument, if present
///
/// Examples:
/// Invoked as `my_command a b c`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: vec![
/// # Value::string("a".to_owned(), null_span),
/// # Value::string("b".to_owned(), null_span),
/// # Value::string("c".to_owned(), null_span),
/// # ],
/// # named: vec![],
/// # };
/// let arg = match call.nth(1) {
/// Some(Value::String { val, .. }) => val,
/// _ => panic!(),
/// };
/// assert_eq!(arg, "b".to_owned());
///
/// let arg = call.nth(7);
/// assert!(arg.is_none());
/// ```
pub fn nth(&self, pos: usize) -> Option<Value> {
self.positional.get(pos).cloned()
}
/// Returns the value of a named argument interpreted as type `T`
///
/// # Examples
/// Invoked as `my_command --foo 123`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: Vec::new(),
/// # named: vec![(
/// # Spanned { item: "foo".to_owned(), span: null_span},
/// # Some(Value::int(123, null_span))
/// # )],
/// # };
/// let foo = call.get_flag::<i64>("foo");
/// assert_eq!(foo.unwrap(), Some(123));
/// ```
///
/// Invoked as `my_command --bar 123`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: Vec::new(),
/// # named: vec![(
/// # Spanned { item: "bar".to_owned(), span: null_span},
/// # Some(Value::int(123, null_span))
/// # )],
/// # };
/// let foo = call.get_flag::<i64>("foo");
/// assert_eq!(foo.unwrap(), None);
/// ```
///
/// Invoked as `my_command --foo abc`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: Vec::new(),
/// # named: vec![(
/// # Spanned { item: "foo".to_owned(), span: null_span},
/// # Some(Value::string("abc".to_owned(), null_span))
/// # )],
/// # };
/// let foo = call.get_flag::<i64>("foo");
/// assert!(foo.is_err());
/// ```
pub fn get_flag<T: FromValue>(&self, name: &str) -> Result<Option<T>, ShellError> {
if let Some(value) = self.get_flag_value(name) {
FromValue::from_value(value).map(Some)
} else {
Ok(None)
}
}
/// Retrieve the Nth and all following positional arguments as type `T`
///
/// # Example
/// Invoked as `my_command zero one two three`:
/// ```
/// # use nu_protocol::{Spanned, Span, Value};
/// # use nu_plugin_protocol::EvaluatedCall;
/// # let null_span = Span::new(0, 0);
/// # let call = EvaluatedCall {
/// # head: null_span,
/// # positional: vec![
/// # Value::string("zero".to_owned(), null_span),
/// # Value::string("one".to_owned(), null_span),
/// # Value::string("two".to_owned(), null_span),
/// # Value::string("three".to_owned(), null_span),
/// # ],
/// # named: Vec::new(),
/// # };
/// let args = call.rest::<String>(0);
/// assert_eq!(args.unwrap(), vec!["zero", "one", "two", "three"]);
///
/// let args = call.rest::<String>(2);
/// assert_eq!(args.unwrap(), vec!["two", "three"]);
/// ```
pub fn rest<T: FromValue>(&self, starting_pos: usize) -> Result<Vec<T>, ShellError> {
self.positional
.iter()
.skip(starting_pos)
.map(|value| FromValue::from_value(value.clone()))
.collect()
}
/// Retrieve the value of an optional positional argument interpreted as type `T`
///
/// Returns the value of a (zero indexed) positional argument of type `T`.
/// Alternatively returns [`None`] if the positional argument does not exist
/// or an error that can be passed back to the shell on error.
pub fn opt<T: FromValue>(&self, pos: usize) -> Result<Option<T>, ShellError> {
if let Some(value) = self.nth(pos) {
FromValue::from_value(value).map(Some)
} else {
Ok(None)
}
}
/// Retrieve the value of a mandatory positional argument as type `T`
///
/// Expect a positional argument of type `T` and return its value or, if the
/// argument does not exist or is of the wrong type, return an error that can
/// be passed back to the shell.
pub fn req<T: FromValue>(&self, pos: usize) -> Result<T, ShellError> {
if let Some(value) = self.nth(pos) {
FromValue::from_value(value)
} else if self.positional.is_empty() {
Err(ShellError::AccessEmptyContent { span: self.head })
} else {
Err(ShellError::AccessBeyondEnd {
max_idx: self.positional.len() - 1,
span: self.head,
})
}
}
}
#[cfg(test)]
mod test {
use super::*;
use nu_protocol::{Span, Spanned, Value};
#[test]
fn call_to_value() {
let call = EvaluatedCall {
head: Span::new(0, 10),
positional: vec![
Value::float(1.0, Span::new(0, 10)),
Value::string("something", Span::new(0, 10)),
],
named: vec![
(
Spanned {
item: "name".to_string(),
span: Span::new(0, 10),
},
Some(Value::float(1.0, Span::new(0, 10))),
),
(
Spanned {
item: "flag".to_string(),
span: Span::new(0, 10),
},
None,
),
],
};
let name: Option<f64> = call.get_flag("name").unwrap();
assert_eq!(name, Some(1.0));
assert!(call.has_flag("flag").unwrap());
let required: f64 = call.req(0).unwrap();
assert!((required - 1.0).abs() < f64::EPSILON);
let optional: Option<String> = call.opt(1).unwrap();
assert_eq!(optional, Some("something".to_string()));
let rest: Vec<String> = call.rest(1).unwrap();
assert_eq!(rest, vec!["something".to_string()]);
}
}