avm1: Add a way to specify numeric tolerance @epsilon when comparin…

…g in `test_method!`

core/src/avm1/test_utils.rs

@@ -30,8 +30,9 @@ where
 }
 
 macro_rules! test_method {
-    ( $test: ident, $name: expr, $object: expr, $($versions: expr => { $([$($arg: expr),*] => $out: expr),* }),* ) => {
+    ( $test: ident, $name: expr, $object: expr, $($versions: expr => { $( $(@epsilon($epsilon: expr))? [$($arg: expr),*] => $out: expr),* }),* ) => {
         #[test]
+        #[allow(unreachable_code)] // the `assert_eq!` at the end, in expansions without `@epsilon`
         fn $test() {
             use $crate::avm1::test_utils::*;
             $(
@@ -43,6 +44,13 @@ macro_rules! test_method {
                         $(
                             let args: Vec<Value> = vec![$($arg.into()),*];
                             let ret = crate::avm1::object::TObject::call_method(&object, name, &args, activation, crate::avm1::function::ExecutionReason::Special)?;
+
+                            // Do a numeric comparison with tolerance if `@epsilon` was given:
+                            $(
+                                assert!(f64::abs($out as f64 - ret.coerce_to_f64(activation)?) < $epsilon as f64, "@epsilon({:?}) {:?} => {:?} in swf {}", $epsilon, args, $out, version);
+                                return Ok(());
+                            )?
+                            // Else, do a generic equality comparison:
                             assert_eq!(ret, $out.into(), "{:?} => {:?} in swf {}", args, $out, version);
                         )*