avm1: Fix this fallback in Function.prototype.call/apply

It should apply for all non-coercible values, not just null/undefined.

Author: moulins

core/src/avm1/globals/function.rs

@@ -3,6 +3,7 @@
 use crate::avm1::activation::Activation;
 use crate::avm1::error::Error;
 use crate::avm1::function::{ExecutionName, ExecutionReason};
+use crate::avm1::parameters::ParametersExt as _;
 use crate::avm1::property_decl::{DeclContext, Declaration, SystemClass};
 use crate::avm1::{Object, Value};
 use crate::string::AvmString;
@@ -50,10 +51,10 @@ pub fn call<'gc>(
     func: Object<'gc>,
     myargs: &[Value<'gc>],
 ) -> Result<Value<'gc>, Error<'gc>> {
-    let this = match myargs.get(0).unwrap_or(&Value::Undefined) {
-        Value::Undefined | Value::Null => activation.global_object(),
-        this_val => this_val.coerce_to_object_or_bare(activation)?,
-    };
+    let this = myargs
+        .try_get_object(activation, 0)?
+        .unwrap_or_else(|| activation.global_object());
+
     let empty = [];
     let args = match myargs.len() {
         0 => &empty,
@@ -82,10 +83,10 @@ pub fn apply<'gc>(
     func: Object<'gc>,
     myargs: &[Value<'gc>],
 ) -> Result<Value<'gc>, Error<'gc>> {
-    let this = match myargs.get(0).unwrap_or(&Value::Undefined) {
-        Value::Undefined | Value::Null => activation.global_object(),
-        this_val => this_val.coerce_to_object_or_bare(activation)?,
-    };
+    let this = myargs
+        .try_get_object(activation, 0)?
+        .unwrap_or_else(|| activation.global_object());
+
     let args_object = myargs.get(1).cloned().unwrap_or(Value::Undefined);
     let length = match args_object {
         Value::Object(a) => a.length(activation)? as usize,

core/src/avm1/parameters.rs

@@ -31,19 +31,14 @@ pub trait ParametersExt<'gc> {
     }
 
     /// Tries to get the value at the given index as an Object.
-    /// The value will be coerced to an Object if it exists.
-    #[expect(dead_code)]
+    /// The value will be coerced to an Object if it exists and is coercible.
     fn try_get_object(
         &self,
         activation: &mut Activation<'_, 'gc>,
         index: usize,
-        undefined_behaviour: UndefinedAs,
     ) -> Result<Option<Object<'gc>>, Error<'gc>> {
         if let Some(value) = self.get_optional(index) {
-            if undefined_behaviour == UndefinedAs::None && value == Value::Undefined {
-                return Ok(None);
-            }
-            Ok(Some(value.coerce_to_object_or_bare(activation)?))
+            value.coerce_to_object(activation)
         } else {
             Ok(None)
         }

tests/tests/swfs/avm1/coerce_to_object_monkeypatch/output.ruffle.txt

@@ -1,2 +1 @@
 num_ticks = 1
-known_failure = true