[mstable] Add mStable strategy (snapshot-labs#93)

* Add mStable strategy

- Combines balances of both stkMTA & stkBPT

* Remove decimals from params

* Add README

* Update src/strategies/mstable/README.md

* Update src/strategies/mstable/examples.json

* Update src/strategies/mstable/index.ts

Co-authored-by: Chaitanya <[email protected]>

src/strategies/index.ts

@@ -157,6 +157,7 @@ import * as hoprBridgedBalance from './hopr-bridged-balance';
 import * as lootCharacterGuilds from './loot-character-guilds';
 import * as cyberkongz from './cyberkongz';
 import * as compLikeVotesInclusive from './comp-like-votes-inclusive';
+import * as mstable from './mstable';
 
 const strategies = {
   coordinape,
@@ -315,7 +316,8 @@ const strategies = {
   'holds-tokens': holdsTokens,
   'loot-character-guilds': lootCharacterGuilds,
   'cyberkongz': cyberkongz,
-  'comp-like-votes-inclusive': compLikeVotesInclusive
+  'comp-like-votes-inclusive': compLikeVotesInclusive,
+  mstable
 };
 
 Object.keys(strategies).forEach(function (strategyName) {

src/strategies/mstable/README.md

@@ -0,0 +1,19 @@
+# mstable
+
+Calls getVotes() on both the stkMTA and stkBPT contracts, these balances are then summed to generate a users vMTA balance.
+
+## Examples
+
+```JSON
+{
+  "strategies": [
+    {
+      "name": "mstable",
+      "params": {
+        "stkBPT": "0xefbe22085d9f29863cfb77eed16d3cc0d927b011",
+        "stkMTA": "0x8f2326316eC696F6d023E37A9931c2b2C177a3D7",
+      }
+    }
+  ]
+}
+```

src/strategies/mstable/examples.json

@@ -0,0 +1,18 @@
+[
+  {
+    "name": "mstable",
+    "strategy": {
+      "name": "mstable",
+      "params": {
+        "stkBPT": "0xefbe22085d9f29863cfb77eed16d3cc0d927b011",
+        "stkMTA": "0x8f2326316eC696F6d023E37A9931c2b2C177a3D7"
+      }
+    },
+    "network": "1",
+    "addresses": [
+      "0x2ee8670d2b936985d5fb1ee968810c155d3bb9ca",
+      "0x19f12c947d25ff8a3b748829d8001ca09a28d46d"
+    ],
+    "snapshot": 13236086
+  }
+]

src/strategies/mstable/index.ts

@@ -0,0 +1,61 @@
+import { formatUnits } from '@ethersproject/units';
+import { multicall } from '../../utils';
+
+export const author = 'chrisjgf';
+export const version = '0.0.1';
+
+const abi = [ 'function getVotes(address account) view returns (uint256)' ];
+
+const chunk = (arr, size) =>
+  Array.from({ length: Math.ceil(arr.length / size) }, (v, i) =>
+    arr.slice(i * size, i * size + size)
+  );
+
+export async function strategy(
+  space,
+  network,
+  provider,
+  addresses,
+  options,
+  snapshot
+): Promise<Record<string, number>> {
+  const blockTag = typeof snapshot === 'number' ? snapshot : 'latest';
+
+  const stkMTAQuery = addresses.map((address: any) => [
+    options.stkMTA,
+    'getVotes',
+    [address]
+  ]);
+
+  const stkBPTQuery = addresses.map((address: any) => [
+    options.stkBPT,
+    'getVotes',
+    [address]
+  ]);
+
+  const response = await multicall(
+    network,
+    provider,
+    abi,
+    [...stkMTAQuery, ...stkBPTQuery],
+    { blockTag }
+  );
+
+  const chunks = chunk(response, addresses.length);
+  const stkMTABalances = chunks[0];
+  const stkBPTBalances = chunks[1];
+
+  return Object.fromEntries(
+    Array(addresses.length)
+      .fill('x')
+      .map((_, i) => [
+        addresses[i],
+        parseFloat(
+          formatUnits(
+            stkMTABalances[i][0].add(stkBPTBalances[i][0]).toString(),
+            18
+          )
+        )
+      ])
+  );
+}