Module wabt::script

Module for parsing WebAssembly script format (a.k.a. wast).

These scripts might be useful to integrate the official spec testsuite into implementations of the wasm execution engines (such as wasmi) and for developing fine-grained tests of runtimes or/and if it isn't desired to use full fledged compilers.

Example

use wabt::script::{ScriptParser, Command, CommandKind, Action, Value};
 
let wast = r#"
;; Define anonymous module with function export named `sub`.
(module 
  (func (export "sub") (param $x i32) (param $y i32) (result i32)
    ;; return x - y;
    (i32.sub
      (get_local $x) (get_local $y)
    )
  )
)
 
;; Assert that invoking export `sub` with parameters (8, 3)
;; should return 5.
(assert_return
  (invoke "sub"
    (i32.const 8) (i32.const 3)
  )
  (i32.const 5)
)
"#;
 
let mut parser = ScriptParser::from_str(wast)?;
while let Some(Command { kind, .. }) = parser.next()? { 
    match kind {
        CommandKind::Module { module, name } => {
            // The module is declared as annonymous.
            assert_eq!(name, None);
 
            // Convert the module into the binary representation and check the magic number.
            let module_binary = module.into_vec()?;
            assert_eq!(&module_binary[0..4], &[0, 97, 115, 109]);
        }
        CommandKind::AssertReturn { action, expected } => {
            assert_eq!(action, Action::Invoke { 
                module: None,
                field: "sub".to_string(),
                args: vec![
                    Value::I32(8),
                    Value::I32(3)
                ],
            });
            assert_eq!(expected, vec![Value::I32(5)]);
        },
        _ => panic!("there are no other commands apart from that defined above"),
    }
}

Structs

Command	Command in the script.
ModuleBinary	This is a handle to get the binary representation of the module.
ScriptParser	Parser which allows to parse WebAssembly script text format.

Enums

Action	Description of action that should be performed on a wasm module.
CommandKind	Script's command.
Error	Error that can happen when parsing spec.
Value	Wasm value