Backported from upstream PR: https://github.com/urfave/cli/pull/1299
---
diff --git a/app_test.go b/app_test.go
index 33024ff..6b3aaa3 100644
--- a/app_test.go
+++ b/app_test.go
@@ -513,18 +513,18 @@ func TestApp_RunAsSubcommandParseFlags(t *testing.T) {
 func TestApp_RunAsSubCommandIncorrectUsage(t *testing.T) {
 	a := App{
 		Flags: []Flag{
-			StringFlag{Name: "--foo"},
+			StringFlag{Name: "foo"},
 		},
 		Writer: bytes.NewBufferString(""),
 	}
 
 	set := flag.NewFlagSet("", flag.ContinueOnError)
-	_ = set.Parse([]string{"", "---foo"})
+	_ = set.Parse([]string{"", "-bar"})
 	c := &Context{flagSet: set}
 
 	err := a.RunAsSubcommand(c)
 
-	expect(t, err, errors.New("bad flag syntax: ---foo"))
+	expect(t, err.Error(), "flag provided but not defined: -bar")
 }
 
 func TestApp_CommandWithFlagBeforeTerminator(t *testing.T) {
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<tr><td><span title='2019-09-29 16:39:19 +0200'>2019-09-29</span></td><td><a href='/guix/commit/gnu/packages/ntp.scm?id=4ecf790e70dd22c204edad269cb661d820864906'>gnu: tlsdate: Build against OpenSSL@1.0.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ntp.scm (tlsdate)[inputs]: Change from OPENSSL to OPENSSL-1.0.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2019-09-08 23:15:31 +0900'>2019-09-08</span></td><td><a href='/guix/commit/gnu/packages/ntp.scm?id=f92cf9d356e5584b073a626bcb27ffb5ed7f99a7'>gnu: openntpd: Fix error CA errors when using constraints.</a><span class='msg-avail'>...<span class='msg-tooltip'>The error printed by nttpd was "constraint: failed to load constraint ca" when
libressl tried loading the file /etc/ssl/cert.pem.  The problem was
investigated as part of fixing issue 37318 (see:
http://debbugs.gnu.org/cgi/bugreport.cgi?bug=37318).

* gnu/packages/ntp.scm (openntpd)[configure-flags]: Use the '--with-cacert'
flag to specify the location of the certificate authority file of libressl.
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2019-03-18 23:42:47 +0100'>2019-03-18</span></td><td><a href='/guix/commit/gnu/packages/ntp.scm?id=0a8c2c98fb0b0727044f85b35f3350ea60e5a6bb'>gnu: ntp: Update to 4.2.8p13.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ntp.scm (ntp): Update to 4.2.8p13.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>