rhai/tests/custom_syntax.rs
2022-12-30 18:07:39 +01:00

355 lines
11 KiB
Rust

#![cfg(not(feature = "no_custom_syntax"))]
use rhai::{
Dynamic, Engine, EvalAltResult, ImmutableString, LexError, ParseErrorType, Position, Scope, INT,
};
#[test]
fn test_custom_syntax() -> Result<(), Box<EvalAltResult>> {
let mut engine = Engine::new();
engine.run("while false {}")?;
// Disable 'while' and make sure it still works with custom syntax
engine.disable_symbol("while");
assert!(matches!(
engine.compile("while false {}").expect_err("should error").err_type(),
ParseErrorType::Reserved(err) if err == "while"
));
assert!(matches!(
engine.compile("let while = 0").expect_err("should error").err_type(),
ParseErrorType::Reserved(err) if err == "while"
));
// Implement ternary operator
engine.register_custom_syntax(
["iff", "$expr$", "?", "$expr$", ":", "$expr$"],
false,
|context, inputs| match context.eval_expression_tree(&inputs[0])?.as_bool() {
Ok(true) => context.eval_expression_tree(&inputs[1]),
Ok(false) => context.eval_expression_tree(&inputs[2]),
Err(typ) => Err(Box::new(EvalAltResult::ErrorMismatchDataType(
"bool".to_string(),
typ.to_string(),
inputs[0].position(),
))),
},
)?;
assert_eq!(
engine.eval::<INT>(
"
let x = 42;
let y = iff x > 40 ? 0 : 123;
y
"
)?,
0
);
assert_eq!(
engine.eval::<INT>(
"
let x = 42;
let y = iff x == 0 ? 0 : 123;
y
"
)?,
123
);
// Custom syntax
engine.register_custom_syntax(
[
"exec", "[", "$ident$", "$symbol$", "$int$", "]", "->", "$block$", "while", "$expr$",
],
true,
|context, inputs| {
let var_name = inputs[0].get_string_value().unwrap();
let op = inputs[1].get_literal_value::<ImmutableString>().unwrap();
let max = inputs[2].get_literal_value::<INT>().unwrap();
let stmt = &inputs[3];
let condition = &inputs[4];
context.scope_mut().push(var_name.to_string(), 0 as INT);
let mut count: INT = 0;
loop {
let done = match op.as_str() {
"<" => count >= max,
"<=" => count > max,
">" => count <= max,
">=" => count < max,
"==" => count != max,
"!=" => count == max,
_ => return Err(format!("Unsupported operator: {op}").into()),
};
if done {
break;
}
// Do not rewind if the variable is upper-case
let _: Dynamic = if var_name.to_uppercase() == var_name {
#[allow(deprecated)] // not deprecated but unstable
context.eval_expression_tree_raw(stmt, false)
} else {
context.eval_expression_tree(stmt)
}?;
count += 1;
context
.scope_mut()
.push(format!("{var_name}{count}"), count);
let stop = !context
.eval_expression_tree(condition)?
.as_bool()
.map_err(|err| {
Box::new(EvalAltResult::ErrorMismatchDataType(
"bool".to_string(),
err.to_string(),
condition.position(),
))
})?;
if stop {
break;
}
}
Ok(count.into())
},
)?;
assert!(matches!(
*engine
.run("let foo = (exec [x<<15] -> { x += 2 } while x < 42) * 10;")
.expect_err("should error"),
EvalAltResult::ErrorRuntime(..)
));
assert_eq!(
engine.eval::<INT>(
"
let x = 0;
let foo = (exec [x<15] -> { x += 2 } while x < 42) * 10;
foo
"
)?,
150
);
assert_eq!(
engine.eval::<INT>(
"
let x = 0;
exec [x<100] -> { x += 1 } while x < 42;
x
"
)?,
42
);
assert_eq!(
engine.eval::<INT>(
"
exec [x<100] -> { x += 1 } while x < 42;
x
"
)?,
42
);
assert_eq!(
engine.eval::<INT>(
"
let foo = 123;
exec [x<15] -> { x += 1 } while x < 42;
foo + x + x1 + x2 + x3
"
)?,
144
);
assert_eq!(
engine.eval::<INT>(
"
let foo = 123;
exec [x<15] -> { let foo = x; x += 1; } while x < 42;
foo
"
)?,
123
);
assert_eq!(
engine.eval::<INT>(
"
let foo = 123;
exec [ABC<15] -> { let foo = ABC; ABC += 1; } while ABC < 42;
foo
"
)?,
14
);
// The first symbol must be an identifier
assert_eq!(
*engine
.register_custom_syntax(["!"], false, |_, _| Ok(Dynamic::UNIT))
.expect_err("should error")
.err_type(),
ParseErrorType::BadInput(LexError::ImproperSymbol(
"!".to_string(),
"Improper symbol for custom syntax at position #1: '!'".to_string()
))
);
// Check self-termination
engine
.register_custom_syntax(["test1", "$block$"], true, |_, _| Ok(Dynamic::UNIT))?
.register_custom_syntax(["test2", "}"], true, |_, _| Ok(Dynamic::UNIT))?
.register_custom_syntax(["test3", ";"], true, |_, _| Ok(Dynamic::UNIT))?;
assert_eq!(engine.eval::<INT>("test1 { x = y + z; } 42")?, 42);
assert_eq!(engine.eval::<INT>("test2 } 42")?, 42);
assert_eq!(engine.eval::<INT>("test3; 42")?, 42);
// Register the custom syntax: var x = ???
engine.register_custom_syntax(
["var", "$ident$", "=", "$expr$"],
true,
|context, inputs| {
let var_name = inputs[0].get_string_value().unwrap();
let expr = &inputs[1];
// Evaluate the expression
let value = context.eval_expression_tree(expr)?;
if !context.scope().is_constant(var_name).unwrap_or(false) {
context.scope_mut().set_value(var_name.to_string(), value);
Ok(Dynamic::UNIT)
} else {
Err(format!("variable {var_name} is constant").into())
}
},
)?;
let mut scope = Scope::new();
assert_eq!(
engine.eval_with_scope::<INT>(&mut scope, "var foo = 42; foo")?,
42
);
assert_eq!(scope.get_value::<INT>("foo"), Some(42));
assert_eq!(scope.len(), 1);
assert_eq!(
engine.eval_with_scope::<INT>(&mut scope, "var foo = 123; foo")?,
123
);
assert_eq!(scope.get_value::<INT>("foo"), Some(123));
assert_eq!(scope.len(), 1);
Ok(())
}
#[test]
fn test_custom_syntax_raw() -> Result<(), Box<EvalAltResult>> {
let mut engine = Engine::new();
engine.register_custom_syntax_with_state_raw(
"hello",
|stream, look_ahead, state| match stream.len() {
0 => unreachable!(),
1 if look_ahead == "\"world\"" => {
*state = Dynamic::TRUE;
Ok(Some("$string$".into()))
}
1 => {
*state = Dynamic::FALSE;
Ok(Some("$ident$".into()))
}
2 => {
match stream[1].as_str() {
"world" if state.as_bool().unwrap_or(false) => Ok(Some("$$world".into())),
"world" => Ok(Some("$$hello".into())),
"kitty" => {
*state = (42 as INT).into();
Ok(None)
}
s => Err(LexError::ImproperSymbol(s.to_string(), String::new())
.into_err(Position::NONE)),
}
}
_ => unreachable!(),
},
true,
|context, inputs, state| {
context.scope_mut().push("foo", 999 as INT);
Ok(match inputs[0].get_string_value().unwrap() {
"world" => match inputs.last().unwrap().get_string_value().unwrap_or("") {
"$$hello" => 0 as INT,
"$$world" => 123456 as INT,
_ => 123 as INT,
},
"kitty" if inputs.len() > 1 => 999 as INT,
"kitty" => state.as_int().unwrap(),
_ => unreachable!(),
}
.into())
},
);
assert_eq!(engine.eval::<INT>(r#"hello "world""#)?, 123456);
assert_eq!(engine.eval::<INT>("hello world")?, 0);
assert_eq!(engine.eval::<INT>("hello kitty")?, 42);
assert_eq!(
engine.eval::<INT>("let foo = 0; (hello kitty) + foo")?,
1041
);
assert_eq!(engine.eval::<INT>("(hello kitty) + foo")?, 1041);
assert_eq!(
*engine
.compile("hello hey")
.expect_err("should error")
.err_type(),
ParseErrorType::BadInput(LexError::ImproperSymbol("hey".to_string(), String::new()))
);
Ok(())
}
#[test]
fn test_custom_syntax_raw2() -> Result<(), Box<EvalAltResult>> {
let mut engine = Engine::new();
engine.register_custom_syntax_with_state_raw(
"#",
|symbols, lookahead, _| match symbols.len() {
1 if lookahead == "-" => Ok(Some("$symbol$".into())),
1 => Ok(Some("$int$".into())),
2 if symbols[1] == "-" => Ok(Some("$int$".into())),
2 => Ok(None),
3 => Ok(None),
_ => unreachable!(),
},
false,
move |_, inputs, _| {
let id = if inputs.len() == 2 {
-inputs[1].get_literal_value::<INT>().unwrap()
} else {
inputs[0].get_literal_value::<INT>().unwrap()
};
Ok(id.into())
},
);
assert_eq!(engine.eval::<INT>("#-1")?, -1);
assert_eq!(engine.eval::<INT>("let x = 41; x + #1")?, 42);
#[cfg(not(feature = "no_object"))]
assert_eq!(engine.eval::<INT>("#-42.abs()")?, 42);
assert_eq!(engine.eval::<INT>("#42/2")?, 21);
assert_eq!(engine.eval::<INT>("sign(#1)")?, 1);
Ok(())
}