From upstream PR: https://github.com/urfave/cli/pull/1299

From: William Wilson <william.wilson@canonical.com>
Date: Tue, 31 Aug 2021 14:19:17 -0500
Subject: Make test case compatible with Go 1.17

As of Go 1.17, the go flag package will panic if given a syntactically invalid
flag. This causes TestApp_RunAsSubCommandIncorrectUsage to panic and therefore
fail. See https://golang.org/doc/go1.17#flag for more information.

---
diff --git a/app_test.go b/app_test.go
index 7c38f6048..76e211d68 100644
--- a/app_test.go
+++ b/app_test.go
@@ -476,18 +476,18 @@ func TestApp_RunAsSubCommandIncorrectUsage(t *testing.T) {
 	a := App{
 		Name: "cmd",
 		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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<div class='path'>path: <a href='/guix/log/?id=aff495c8eb3953fe718cb15d3ff612aa306bba74&amp;showmsg=1'>root</a>/<a href='/guix/log/m4?id=aff495c8eb3953fe718cb15d3ff612aa306bba74&amp;showmsg=1'>m4</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/m4?id=aff495c8eb3953fe718cb15d3ff612aa306bba74'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2021-03-23 23:19:57 -0700'>2021-03-23</span></td><td class='logsubject'><a href='/guix/commit/m4?id=a16eb6c5f97f136b678540ba61f12b2c08e43e13'>Add powerpc64le-linux as a supported Guix architecture.</a></td><td>Chris Marusich</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
This makes powerpc64le-linux a supported architecture for Guix, but not for
Guix System.

* Makefile.am (SUPPORTED_SYSTEMS): Add an entry for powerpc64le-linux.
* etc/guix-install.sh (chk_sys_arch): Same.
* guix/packages.scm (%supported-systems): Same.
* m4/guix.m4 (GUIX_ASSERT_SUPPORTED_SYSTEM): Same.
* tests/guix-build.sh (all_systems): Same.


</td></tr>
<tr class='logheader'><td><span title='2021-03-17 12:03:23 +0100'>2021-03-17</span></td><td class='logsubject'><a href='/guix/commit/m4?id=62a091368df3bab499142d06f5114a73915c71f2'>maint: Check whether Guile-zlib is recent enough.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
This is a followup to a04aef2430645357d7796969d4b6453478ff8a3f.

* m4/guix.m4 (GUIX_CHECK_GUILE_ZLIB): New macro.
* configure.ac: Use it when checking for Guile-zlib.


</td></tr>
<tr class='logheader'><td><span title='2021-02-04 09:23:39 +0100'>2021-02-04</span></td><td class='logsubject'><a href='/guix/commit/m4?id=55daad123e896c0e83361496cf49625289ee3571'>build: Add '--with-channel-commit' and related configure flags.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
Partially fixes &lt;https://bugs.gnu.org/45896&gt;.

* m4/guix.m4 (GUIX_CHANNEL_METADATA): New macro.
* configure.ac: Use it.
* guix/config.scm.in (%channel-metadata): Adjust accordingly.


</td></tr>
<tr class='logheader'><td><span title='2020-12-11 19:06:53 +0100'>2020-12-11</span></td><td class='logsubject'><a href='/guix/commit/m4?id=dbdae9f96f11a006993b659e0e7fd5cbf467f844'>maint: Avoid macros obsolete in Autoconf 2.70.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* configure.ac: Require Autoconf 2.69.  Use 'AS_HELP_STRING' instead of
'AC_HELP_STRING'.
* m4/guix.m4: Likewise.
* config-daemon.ac: Use 'AC_CONFIG_HEADERS' instead of the singular
variant.


</td></tr>
<tr class='logheader'><td><span title='2020-10-22 17:10:25 +0200'>2020-10-22</span></td><td class='logsubject'><a href='/guix/commit/m4?id=59bb1ae3a9aeae75a75b20090253613a7a8800d8'>git: Require Guile-Git 0.3.0 or later.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* guix/git.scm (auth-supported?): Remove.
(clone*): Inline code that was dependent on AUTH-SUPPORTED?.
(update-cached-checkout): Likewise.
(resolve-reference): Remove check for 'object-lookup-prefix' and use it
unconditionally.
(load-git-submodules): Remove.
(update-submodules): Use 'repository-submodules', 'submodule-lookup',
etc. unconditionally.
(update-cached-checkout): Use 'repository-close!' unconditionally.
* m4/guix.m4 (GUIX_CHECK_GUILE_GIT): New macro.
* configure.ac: Use it and error out when it fails.
* doc/guix.texi (Requirements): Bump to Guile-Git 0.3.0.


</td></tr>