Extend ssz-static testing

tests/ef_tests/src/eth_specs.rs

@@ -0,0 +1,23 @@
+use types::{EthSpec, typenum::{U64, U8}, ChainSpec, FewValidatorsEthSpec};
+use serde_derive::{Serialize, Deserialize};
+
+/// "Minimal" testing specification, as defined here:
+///
+/// https://github.com/ethereum/eth2.0-specs/blob/v0.6.1/configs/constant_presets/minimal.yaml
+///
+/// Spec v0.6.1
+#[derive(Clone, PartialEq, Debug, Default, Serialize, Deserialize)]
+pub struct MinimalEthSpec;
+
+impl EthSpec for MinimalEthSpec {
+    type ShardCount = U8;
+    type SlotsPerHistoricalRoot = U64;
+    type LatestRandaoMixesLength = U64;
+    type LatestActiveIndexRootsLength = U64;
+    type LatestSlashedExitLength = U64;
+
+    fn spec() -> ChainSpec {
+        // TODO: this spec is likely incorrect!
+        FewValidatorsEthSpec::spec()
+    }
+}