Made function assertions work with the new wrappers

contracts/integrations/test/fuzz_tests/pool_membership_test.ts

@@ -0,0 +1,53 @@
+import { blockchainTests } from '@0x/contracts-test-utils';
+import * as _ from 'lodash';
+
+import { PoolMember } from '../framework/actors/pool_member';
+import { PoolOperator } from '../framework/actors/pool_operator';
+import { AssertionResult } from '../framework/assertions/function_assertion';
+import { BlockchainBalanceStore } from '../framework/balances/blockchain_balance_store';
+import { DeploymentManager } from '../framework/deployment_manager';
+import { Simulation, SimulationEnvironment } from '../framework/simulation';
+
+class PoolMembershipSimulation extends Simulation {
+    protected async *_assertionGenerator(): AsyncIterableIterator<AssertionResult | void> {
+        const { deployment } = this.environment;
+
+        const operator = new PoolOperator({
+            name: 'operator',
+            deployment,
+            simulationEnvironment: this.environment,
+        });
+
+        const member = new PoolMember({
+            name: 'member',
+            deployment,
+            simulationEnvironment: this.environment,
+        });
+
+        const actions = [
+            operator.simulationActions.validCreateStakingPool,
+            member.simulationActions.validJoinStakingPool,
+        ];
+
+        while (true) {
+            const action = _.sample(actions);
+            yield (await action!.next()).value; // tslint:disable-line:no-non-null-assertion
+        }
+    }
+}
+
+blockchainTests('pool membership fuzz test', env => {
+    it('fuzz', async () => {
+        const deployment = await DeploymentManager.deployAsync(env, {
+            numErc20TokensToDeploy: 0,
+            numErc721TokensToDeploy: 0,
+            numErc1155TokensToDeploy: 0,
+        });
+
+        const balanceStore = new BlockchainBalanceStore({}, {});
+
+        const simulationEnv = new SimulationEnvironment(deployment, balanceStore);
+        const simulation = new PoolMembershipSimulation(simulationEnv);
+        return simulation.fuzzAsync();
+    });
+});