3 files changed, 63 insertions, 0 deletions
diff --git a/packages/subproviders/src/index.ts b/packages/subproviders/src/index.ts
index 67d52ee25..4da405ec0 100644
--- a/packages/subproviders/src/index.ts
+++ b/packages/subproviders/src/index.ts
@@ -6,6 +6,8 @@ import {
 
 import { LedgerEthereumClient } from './types';
 
+export { EmptyWalletSubprovider } from './subproviders/empty_wallet_subprovider';
+export { FakeGasEstimateSubprovider } from './subproviders/fake_gas_estimate_subprovider';
 export { InjectedWeb3Subprovider } from './subproviders/injected_web3';
 export { RedundantRPCSubprovider } from './subproviders/redundant_rpc';
 export { LedgerSubprovider } from './subproviders/ledger';
diff --git a/packages/subproviders/src/subproviders/empty_wallet_subprovider.ts b/packages/subproviders/src/subproviders/empty_wallet_subprovider.ts
new file mode 100644
index 000000000..8c1fdfdb2
--- /dev/null
+++ b/packages/subproviders/src/subproviders/empty_wallet_subprovider.ts
@@ -0,0 +1,27 @@
+import { JSONRPCPayload } from '@0xproject/types';
+
+/*
+ * This class implements the web3-provider-engine subprovider interface and returns
+ * that the provider has no addresses when queried.
+ * Source: https://github.com/MetaMask/provider-engine/blob/master/subproviders/subprovider.js
+ */
+export class EmptyWalletSubprovider {
+    // This method needs to be here to satisfy the interface but linter wants it to be static.
+    // tslint:disable-next-line:prefer-function-over-method
+    public handleRequest(payload: JSONRPCPayload, next: () => void, end: (err: Error | null, result: any) => void) {
+        switch (payload.method) {
+            case 'eth_accounts':
+                end(null, []);
+                return;
+
+            default:
+                next();
+                return;
+        }
+    }
+    // Required to implement this method despite not needing it for this subprovider
+    // tslint:disable-next-line:prefer-function-over-method
+    public setEngine(engine: any) {
+        // noop
+    }
+}
diff --git a/packages/subproviders/src/subproviders/fake_gas_estimate_subprovider.ts b/packages/subproviders/src/subproviders/fake_gas_estimate_subprovider.ts
new file mode 100644
index 000000000..b455a0ed7
--- /dev/null
+++ b/packages/subproviders/src/subproviders/fake_gas_estimate_subprovider.ts
@@ -0,0 +1,34 @@
+import { JSONRPCPayload } from '@0xproject/types';
+
+/*
+ * This class implements the web3-provider-engine subprovider interface and returns
+ * the constant gas estimate when queried.
+ * HACK: We need this so that our tests don't use testrpc gas estimation which sometimes kills the node.
+ * Source: https://github.com/trufflesuite/ganache-cli/issues/417
+ * Source: https://github.com/trufflesuite/ganache-cli/issues/437
+ * Source: https://github.com/MetaMask/provider-engine/blob/master/subproviders/subprovider.js
+ */
+export class FakeGasEstimateSubprovider {
+    private _constantGasAmount: number;
+    constructor(constantGasAmount: number) {
+        this._constantGasAmount = constantGasAmount;
+    }
+    // This method needs to be here to satisfy the interface but linter wants it to be static.
+    // tslint:disable-next-line:prefer-function-over-method
+    public handleRequest(payload: JSONRPCPayload, next: () => void, end: (err: Error | null, result: any) => void) {
+        switch (payload.method) {
+            case 'eth_estimateGas':
+                end(null, this._constantGasAmount);
+                return;
+
+            default:
+                next();
+                return;
+        }
+    }
+    // Required to implement this method despite not needing it for this subprovider
+    // tslint:disable-next-line:prefer-function-over-method
+    public setEngine(engine: any) {
+        // noop
+    }
+}