Validate that setSuiteProperty and setSpecProperty args are cloneable

src/core/Spec.js

@@ -70,8 +70,12 @@ getJasmineRequireObj().Spec = function(j$) {
       return this.result.properties[key];
     }
 
-    // TODO: throw if the key or value is not structred cloneable
     setSpecProperty(key, value) {
+      // Key and value will eventually be cloned during reporting. The error
+      // thrown at that point if they aren't cloneable isn't very helpful.
+      // Throw a better one now.
+      j$.util.assertStructuredCloneable(key, 'Key');
+      j$.util.assertStructuredCloneable(value, 'Value');
       this.result.properties = this.result.properties || {};
       this.result.properties[key] = value;
     }

src/core/Suite.js

@@ -31,6 +31,11 @@ getJasmineRequireObj().Suite = function(j$) {
     }
 
     setSuiteProperty(key, value) {
+      // Key and value will eventually be cloned during reporting. The error
+      // thrown at that point if they aren't cloneable isn't very helpful.
+      // Throw a better one now.
+      j$.util.assertStructuredCloneable(key, 'Key');
+      j$.util.assertStructuredCloneable(value, 'Value');
       this.result.properties = this.result.properties || {};
       this.result.properties[key] = value;
     }

src/core/util.js

@@ -80,5 +80,13 @@ getJasmineRequireObj().util = function(j$) {
     }
   };
 
+  util.assertStructuredCloneable = function(v, msgPrefix) {
+    try {
+      structuredClone(v);
+    } catch (e) {
+      throw new Error(`${msgPrefix} can't be cloned`, { cause: e });
+    }
+  };
+
   return util;
 };