fix: use lodash flatMap to stay compatible with node 10

Author: LexLuengas

src/util.ts

@@ -11,6 +11,7 @@ import * as qs from 'qs';
 import { ResponseParsingError } from '../types/errors';
 import { ValidationResults } from '../types/validation';
 import * as rp from 'request-promise-native';
+import { flatMap } from 'lodash';
 
 function isSwaggerV2(apiDoc: any): boolean {
   return apiDoc.swagger === '2.0';
@@ -254,13 +255,15 @@ export interface CliFlags {
  * @param flags
  */
 export function buildCliArguments(flags: Array<CliFlags>): Array<string> {
-  return flags
-    .filter(({ value }) => typeof value === 'string' || value === true)
-    .flatMap(({ flag, value }) => {
-      const args = [flag];
-      if (typeof value === 'string') {
-        args.push(value);
-      }
-      return args;
-    });
+  const effectiveFlags = flags.filter(
+    ({ value }) => typeof value === 'string' || value === true,
+  );
+
+  return flatMap(effectiveFlags, ({ flag, value }) => {
+    const args = [flag];
+    if (typeof value === 'string') {
+      args.push(value);
+    }
+    return args;
+  });
 }

test/util/process.ts

@@ -1,16 +1,19 @@
 import { exec as _exec } from 'child_process';
 import * as util from 'util';
+import { flatMap } from 'lodash';
 import findProcess = require('find-process');
 
 const exec = util.promisify(_exec);
 
-export async function killNodeProcesses(ports: Array<string | number>): Promise<any> {
+export async function killNodeProcesses(
+  ports: Array<string | number>,
+): Promise<any> {
   const processResults = await Promise.all(
     ports.map((port) => findProcess('port', port)),
   );
   return killProcesses(
-    processResults.flatMap((results) =>
-      results.flatMap((process) =>
+    flatMap(processResults, (results) =>
+      flatMap(results, (process) =>
         process.cmd.includes('node') ? process.pid : [],
       ),
     ),