accounts/abi: minor changes in error messages

accounts/abi/argument.go

@@ -159,6 +159,9 @@ func (arguments Arguments) unpackTuple(v interface{}, marshalledValues []interfa
 			}
 		}
 	case reflect.Slice, reflect.Array:
+		if value.Len() < len(marshalledValues) {
+			return fmt.Errorf("abi: insufficient number of arguments for unpack, want %d, got %d", len(arguments), value.Len())
+		}
 		for i := 0; i < value.Len(); i++ {
 			// Skip indexed fields
 			if arguments[i].Indexed {

accounts/abi/event_test.go

@@ -312,14 +312,14 @@ func TestEventTupleUnpack(t *testing.T) {
 		&[]interface{}{common.Address{}, new(big.Int)},
 		&[]interface{}{},
 		jsonEventPledge,
-		"abi: insufficient number of elements in the list/array for unpack, want 3, got 2",
+		"abi: insufficient number of arguments for unpack, want 3, got 2",
 		"Can not unpack Pledge event into too short slice",
 	}, {
 		pledgeData1,
 		new(map[string]interface{}),
 		&[]interface{}{},
 		jsonEventPledge,
-		"abi: cannot unmarshal tuple into map[string]interface {}",
+		"abi:[2] cannot unmarshal tuple in to map[string]interface {}",
 		"Can not unpack Pledge event into map",
 	}, {
 		mixedCaseData1,

accounts/abi/unpack_test.go

@@ -367,7 +367,7 @@ func TestMethodMultiReturn(t *testing.T) {
 	}, {
 		&[]interface{}{new(int)},
 		&[]interface{}{},
-		"abi: insufficient number of elements in the list/array for unpack, want 2, got 1",
+		"abi: insufficient number of arguments for unpack, want 2, got 1",
 		"Can not unpack into a slice with wrong types",
 	}}
 	for _, tc := range testCases {