Create dev-utils with blockchainLifecycle in it

1 files changed, 26 insertions, 0 deletions

diff --git a/packages/dev-utils/src/blockchain_lifecycle.ts b/packages/dev-utils/src/blockchain_lifecycle.ts
new file mode 100644
index 000000000..19c5ac184
--- /dev/null
+++ b/packages/dev-utils/src/blockchain_lifecycle.ts
@@ -0,0 +1,26 @@
+import {RPC} from './rpc';
+
+export class BlockchainLifecycle {
+    private rpc: RPC;
+    private snapshotIdsStack: number[];
+    constructor(url: string) {
+        this.rpc = new RPC(url);
+        this.snapshotIdsStack = [];
+    }
+    // TODO: In order to run these tests on an actual node, we should check if we are running against
+    // TestRPC, if so, use snapshots, otherwise re-deploy contracts before every test
+    public async startAsync(): Promise<void> {
+        const snapshotId = await this.rpc.takeSnapshotAsync();
+        this.snapshotIdsStack.push(snapshotId);
+    }
+    public async revertAsync(): Promise<void> {
+        const snapshotId = this.snapshotIdsStack.pop() as number;
+        const didRevert = await this.rpc.revertSnapshotAsync(snapshotId);
+        if (!didRevert) {
+            throw new Error(`Snapshot with id #${snapshotId} failed to revert`);
+        }
+    }
+    public async mineABlock(): Promise<void> {
+        await this.rpc.mineBlockAsync();
+    }
+}