Modify get-holding to return null for non-existent accounts

Author: mikera

convex-core/src/main/cvx/convex/asset.cvx

@@ -192,7 +192,7 @@
     (recur path *address*))
 
   ([path owner]
-    (query ;; external call, so uery to avoid re-entrant secuity risks
+    (query ;; external call, so use query to avoid re-entrant secuity risks
       (call path (balance owner)))))
 
 (defn burn 

convex-core/src/main/java/convex/core/lang/Core.java

@@ -1174,7 +1174,8 @@ public  Context invoke(Context context, ACell[] args) {
 			if (address == null) return context.withCastError(args[0], Types.ADDRESS);
 
 			AccountStatus as=context.getAccountStatus(address);
-			if (as==null) return context.withError(ErrorCodes.NOBODY,"Account "+address+" does not exist to get holdings");
+			if (as==null) return context.withResult(Juice.LOOKUP, null);
+			
 			BlobMap<Address,ACell> holdings=as.getHoldings();
 
 			// we get the target accounts holdings for the currently executing account

convex-core/src/test/java/convex/core/lang/CoreTest.java

@@ -4680,7 +4680,9 @@ public void testSpecialEdgeCases() {
 		assertNull(eval(ctx,"(get-holding VILLAIN)"));
 		assertCastError(step(ctx,"(get-holding :foo)"));
 		assertCastError(step(ctx,"(get-holding nil)"));
-		assertNobodyError(step(ctx,"(get-holding NOONE)"));
+		
+		// NOTE: holdings are nil for non-existent accounts, better for default behaviour
+		assertNull(eval(ctx,"(get-holding NOONE)"));
 
 		// OK to set holding for a real owner account
 	    assertEquals(100L,evalL(ctx,"(set-holding VILLAIN 100)"));

convex-core/src/test/java/convex/lib/AssetTester.java

@@ -54,6 +54,7 @@ public static void doFungibleTests (Context ctx, ACell token, Address user) {
 			assertEquals(0L,evalL(ctx,"(asset/balance token (deploy nil))"));
 			assertEquals(0L,evalL(ctx,"(asset/balance token (create-account *key*))"));
 			assertEquals(0L,evalL(ctx,"(asset/get-offer token (create-account *key*) (deploy nil))"));
+			assertEquals(0L,evalL(ctx,"(asset/balance token #675475647)"));
 		}
 
 		// New Address gets zero offers