fix: division by 0 error when both reserves are 0 (#1632)

* set pair to invalid if both reserves are 0

* consider reserve0/1=0 as no liquidity

src/state/mint/hooks.ts

@@ -83,7 +83,14 @@ export function useDerivedMintInfo(
   const totalSupply = useTotalSupply(pair?.liquidityToken)
 
   const noLiquidity: boolean =
-    pairState === PairState.NOT_EXISTS || Boolean(totalSupply && JSBI.equal(totalSupply.quotient, ZERO))
+    pairState === PairState.NOT_EXISTS ||
+    Boolean(totalSupply && JSBI.equal(totalSupply.quotient, ZERO)) ||
+    Boolean(
+      pairState === PairState.EXISTS &&
+        pair &&
+        JSBI.equal(pair.reserve0.quotient, ZERO) &&
+        JSBI.equal(pair.reserve1.quotient, ZERO)
+    )
 
   // balances
   const balances = useCurrencyBalances(account ?? undefined, [