80 lines
2.6 KiB
Rust
80 lines
2.6 KiB
Rust
use serde::{Deserialize, Serialize};
|
|
use tree_sitter::Node;
|
|
|
|
use crate::{AbstractTree, Error, Identifier, Map, Result, Statement, Value};
|
|
|
|
#[derive(Debug, Clone, Serialize, Deserialize, Eq, PartialEq, PartialOrd, Ord)]
|
|
pub struct IdentifierAssignment {
|
|
identifier: Identifier,
|
|
operator: AssignmentOperator,
|
|
statement: Statement,
|
|
}
|
|
|
|
#[derive(Debug, Clone, Serialize, Deserialize, Eq, PartialEq, PartialOrd, Ord)]
|
|
pub enum AssignmentOperator {
|
|
Equal,
|
|
PlusEqual,
|
|
MinusEqual,
|
|
}
|
|
|
|
impl AbstractTree for IdentifierAssignment {
|
|
fn from_syntax_node(source: &str, node: Node) -> Result<Self> {
|
|
let identifier_node = node.child(0).unwrap();
|
|
let identifier = Identifier::from_syntax_node(source, identifier_node)?;
|
|
|
|
let operator_node = node.child(1).unwrap().child(0).unwrap();
|
|
let operator = match operator_node.kind() {
|
|
"=" => AssignmentOperator::Equal,
|
|
"+=" => AssignmentOperator::PlusEqual,
|
|
"-=" => AssignmentOperator::MinusEqual,
|
|
_ => {
|
|
return Err(Error::UnexpectedSyntaxNode {
|
|
expected: "=, += or -=",
|
|
actual: operator_node.kind(),
|
|
location: operator_node.start_position(),
|
|
relevant_source: source[operator_node.byte_range()].to_string(),
|
|
})
|
|
}
|
|
};
|
|
|
|
let statement_node = node.child(2).unwrap();
|
|
let statement = Statement::from_syntax_node(source, statement_node)?;
|
|
|
|
Ok(IdentifierAssignment {
|
|
identifier,
|
|
operator,
|
|
statement,
|
|
})
|
|
}
|
|
|
|
fn run(&self, source: &str, context: &mut Map) -> Result<Value> {
|
|
let key = self.identifier.inner().clone();
|
|
let value = self.statement.run(source, context)?;
|
|
let mut context = context.variables_mut();
|
|
|
|
let new_value = match self.operator {
|
|
AssignmentOperator::PlusEqual => {
|
|
if let Some(mut previous_value) = context.get(&key).cloned() {
|
|
previous_value += value;
|
|
previous_value
|
|
} else {
|
|
Value::Empty
|
|
}
|
|
}
|
|
AssignmentOperator::MinusEqual => {
|
|
if let Some(mut previous_value) = context.get(&key).cloned() {
|
|
previous_value -= value;
|
|
previous_value
|
|
} else {
|
|
Value::Empty
|
|
}
|
|
}
|
|
AssignmentOperator::Equal => value,
|
|
};
|
|
|
|
context.insert(key, new_value);
|
|
|
|
Ok(Value::Empty)
|
|
}
|
|
}
|