From 8213b7bfa0eea9a55bdef96f8b46cc9e918799c7 Mon Sep 17 00:00:00 2001
From: Mael LE GUEN <mael.leguen@laposte.fr>
Date: Wed, 11 Sep 2019 12:22:35 +0200
Subject: [PATCH 1/3] fix: #1335: async middleware called twice

Closes #1335
---
 lib/middleware.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/middleware.js b/lib/middleware.js
index 9f9c19696..56dab7527 100644
--- a/lib/middleware.js
+++ b/lib/middleware.js
@@ -40,8 +40,7 @@ function applyMiddleware (argv, yargs, middlewares, beforeValidation) {
   const beforeValidationError = new Error('middleware cannot return a promise when applyBeforeValidation is true')
   return middlewares
     .reduce((accumulation, middleware) => {
-      if (middleware.applyBeforeValidation !== beforeValidation &&
-          !isPromise(accumulation)) {
+      if (middleware.applyBeforeValidation !== beforeValidation) {
         return accumulation
       }
 

From f47f40884ed8943745f3bbeb3acf61eabc875d2a Mon Sep 17 00:00:00 2001
From: Mael LE GUEN <mael.leguen@laposte.fr>
Date: Wed, 11 Sep 2019 14:01:44 +0200
Subject: [PATCH 2/3] add test to reproduce #1335

---
 test/middleware.js | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/test/middleware.js b/test/middleware.js
index dd6638c4e..886c36225 100644
--- a/test/middleware.js
+++ b/test/middleware.js
@@ -145,6 +145,36 @@ describe('middleware', () => {
         .exitProcess(false)
         .parse()
     })
+
+    it('calls an async middleware only once for nested subcommands', (done) => {
+      let callCount = 0
+      let argv = yargs('cmd subcmd')
+        .command(
+          'cmd',
+          'cmd command',
+          function (yargs) {
+            yargs.command(
+              'subcmd',
+              'subcmd command',
+              function (yargs) {}
+            )
+          }
+        )
+        .middleware(async (argv) => {
+          callCount++
+          return argv
+        })
+        .parse()
+
+      if (!(argv instanceof Promise)) done('argv should be a Promise')
+
+      argv
+        .then(() => {
+          callCount.should.equal(1)
+          done()
+        })
+        .catch(err => done(err))
+    })
   })
 
   // see: https://github.com/yargs/yargs/issues/1281

From 4c4ed928143b0913c94d826c8aa74d71abb062a5 Mon Sep 17 00:00:00 2001
From: Mael LE GUEN <mael.leguen@laposte.fr>
Date: Wed, 18 Sep 2019 10:53:50 +0200
Subject: [PATCH 3/3] fix: replace aync by a Promise in test for #1335

---
 test/middleware.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/middleware.js b/test/middleware.js
index 886c36225..5ea318935 100644
--- a/test/middleware.js
+++ b/test/middleware.js
@@ -160,10 +160,10 @@ describe('middleware', () => {
             )
           }
         )
-        .middleware(async (argv) => {
+        .middleware((argv) => new Promise((resolve) => {
           callCount++
-          return argv
-        })
+          resolve(argv)
+        }))
         .parse()
 
       if (!(argv instanceof Promise)) done('argv should be a Promise')