Move TestRig into its own crate

beacon_node/beacon_chain/test_harness/tests/chain.rs

@@ -0,0 +1,28 @@
+use test_harness::TestRig;
+use types::ChainSpec;
+
+#[test]
+fn it_can_build_on_genesis_block() {
+    let validator_count = 2;
+    let mut rig = TestRig::new(ChainSpec::foundation(), validator_count);
+
+    rig.advance_chain_with_block();
+}
+
+#[test]
+#[ignore]
+fn it_can_produce_past_first_epoch_boundary() {
+    let validator_count = 2;
+    let mut rig = TestRig::new(ChainSpec::foundation(), validator_count);
+
+    let blocks = rig.spec.epoch_length + 1;
+
+    for _ in 0..blocks {
+        rig.advance_chain_with_block();
+    }
+    let dump = rig.chain_dump().expect("Chain dump failed.");
+
+    assert_eq!(dump.len() as u64, blocks + 1); // + 1 for genesis block.
+
+    rig.dump_to_file("/tmp/chaindump.json".to_string(), &dump);
+}