Use Object.assign to prevent TypeScript error

The use of the spread opertor causes issues in TypeScript 3.9.x
To avoid this issue we use Object.assign to return on object with
default values.

TypeScript error:
error TS2783: '<XYZ>' is specified more than once, so this usage will be overwritten.

See Travis build with errors:
https://travis-ci.org/github/joule-labs/joule-extension/builds/713053315

Related TypeScript issues:

microsoft/TypeScript#39671
microsoft/TypeScript#38535

src/lnd/http/index.ts

@@ -45,25 +45,29 @@ export class LndHttpClient implements T.LndAPI {
       channels: [],
     }).then((res) => {
       // Default attributes for channels
-      res.channels = res.channels.map((channel) => ({
-        status: T.CHANNEL_STATUS.OPEN,
-        csv_delay: 0,
-        num_updates: 0,
-        private: false,
-        pending_htlcs: [],
-        remote_balance: '0',
-        commit_weight: '0',
-        capacity: '0',
-        local_balance: '0',
-        total_satoshis_received: '0',
-        active: false,
-        commit_fee: '0',
-        fee_per_kw: '0',
-        unsettled_balance: '0',
-        total_satoshis_sent: '0',
-        remote_node_pub: (channel as any).remote_pubkey,
-        ...channel,
-      }));
+      res.channels = res.channels.map((channel) => {
+        return Object.assign(
+          {
+            status: T.CHANNEL_STATUS.OPEN,
+            csv_delay: 0,
+            num_updates: 0,
+            private: false,
+            pending_htlcs: [],
+            remote_balance: '0',
+            commit_weight: '0',
+            capacity: '0',
+            local_balance: '0',
+            total_satoshis_received: '0',
+            active: false,
+            commit_fee: '0',
+            fee_per_kw: '0',
+            unsettled_balance: '0',
+            total_satoshis_sent: '0',
+            remote_node_pub: (channel as any).remote_pubkey,
+          },
+          channel,
+        );
+      });
       return res;
     });
   };
@@ -160,12 +164,16 @@ export class LndHttpClient implements T.LndAPI {
     return this.request<T.GetTransactionsResponse>('GET', '/v1/transactions', undefined, {
       transactions: [],
     }).then((res) => {
-      res.transactions = res.transactions.map((tx) => ({
-        total_fees: '0',
-        amount: '0',
-        num_confirmations: 0,
-        ...tx,
-      }));
+      res.transactions = res.transactions.map((tx) => {
+        return Object.assign(
+          {
+            total_fees: '0',
+            amount: '0',
+            num_confirmations: 0,
+          },
+          tx,
+        );
+      });
       return res;
     });
   };
@@ -174,11 +182,15 @@ export class LndHttpClient implements T.LndAPI {
     return this.request<T.GetPaymentsResponse>('GET', '/v1/payments', undefined, {
       payments: [],
     }).then((res) => {
-      res.payments = res.payments.map((t) => ({
-        fee: '0',
-        path: [],
-        ...t,
-      }));
+      res.payments = res.payments.map((t) => {
+        return Object.assign(
+          {
+            fee: '0',
+            path: [],
+          },
+          t,
+        );
+      });
       return res;
     });
   };
@@ -195,11 +207,15 @@ export class LndHttpClient implements T.LndAPI {
       },
     ).then((res) => {
       // Default attributes for channels
-      res.invoices = res.invoices.map((invoice) => ({
-        route_hints: [],
-        settled: false,
-        ...invoice,
-      }));
+      res.invoices = res.invoices.map((invoice) => {
+        return Object.assign(
+          {
+            route_hints: [],
+            settled: false,
+          },
+          invoice,
+        );
+      });
       return res;
     });
   };
@@ -243,11 +259,15 @@ export class LndHttpClient implements T.LndAPI {
       { routes: [] },
     ).then((res) => {
       // Default attributes for channels
-      res.routes = res.routes.map((route) => ({
-        total_fees: '0',
-        total_fees_msat: '0',
-        ...route,
-      }));
+      res.routes = res.routes.map((route) => {
+        return Object.assign(
+          {
+            total_fees: '0',
+            total_fees_msat: '0',
+          },
+          route,
+        );
+      });
       return res;
     });
   };
@@ -290,14 +310,18 @@ export class LndHttpClient implements T.LndAPI {
       peers: [],
     }).then((res) => {
       // Default attributes for peers
-      res.peers = res.peers.map((peer) => ({
-        ping_time: '0',
-        sat_sent: '0',
-        sat_recv: '0',
-        bytes_sent: '0',
-        bytes_recv: '0',
-        ...peer,
-      }));
+      res.peers = res.peers.map((peer) => {
+        return Object.assign(
+          {
+            ping_time: '0',
+            sat_sent: '0',
+            sat_recv: '0',
+            bytes_sent: '0',
+            bytes_recv: '0',
+          },
+          peer,
+        );
+      });
       return res;
     });
   };
@@ -314,11 +338,13 @@ export class LndHttpClient implements T.LndAPI {
       '/v1/channels',
       params,
     ).then((res) => {
-      return {
-        output_index: '0',
-        funding_txid_str: txIdBytesToHex(res.funding_txid_bytes),
-        ...res,
-      };
+      return Object.assign(
+        {
+          output_index: '0',
+          funding_txid_str: txIdBytesToHex(res.funding_txid_bytes),
+        },
+        res,
+      );
     });
   };