fix: don't remove flag value that matches subcommand name

When the command searches args to find the arg matching a
particular subcommand name, it needs to ignore flag values,
as it is possible that the value for a flag might match
the name of the sub command.

This change improves argsMinusFirstX() to ignore flag values
when it searches for the X to exclude from the result.

Fixes spf13/cobra#1777

Merge spf13/cobra#1781

Author: brianpursley

command.go

@@ -666,13 +666,37 @@ Loop:
 
 // argsMinusFirstX removes only the first x from args.  Otherwise, commands that look like
 // openshift admin policy add-role-to-user admin my-user, lose the admin argument (arg[4]).
-func argsMinusFirstX(args []string, x string) []string {
-	for i, y := range args {
-		if x == y {
-			var ret []string
-			ret = append(ret, args[:i]...)
-			ret = append(ret, args[i+1:]...)
-			return ret
+// Special care needs to be taken not to remove a flag value.
+func (c *Command) argsMinusFirstX(args []string, x string) []string {
+	if len(args) == 0 {
+		return args
+	}
+	c.mergePersistentFlags()
+	flags := c.Flags()
+
+Loop:
+	for pos := 0; pos < len(args); pos++ {
+		s := args[pos]
+		switch {
+		case s == "--":
+			// -- means we have reached the end of the parseable args. Break out of the loop now.
+			break Loop
+		case strings.HasPrefix(s, "--") && !strings.Contains(s, "=") && !isBoolFlag(s[2:], flags):
+			fallthrough
+		case strings.HasPrefix(s, "-") && !strings.Contains(s, "=") && len(s) == 2 && !isShortBoolFlag(s[1:], flags):
+			// This is a flag without a default value, and an equal sign is not used. Increment pos in order to skip
+			// over the next arg, because that is the value of this flag.
+			pos++
+			continue
+		case !strings.HasPrefix(s, "-"):
+			// This is not a flag or a flag value. Check to see if it matches what we're looking for, and if so,
+			// return the args, excluding the one at this position.
+			if s == x {
+				ret := []string{}
+				ret = append(ret, args[:pos]...)
+				ret = append(ret, args[pos+1:]...)
+				return ret
+			}
 		}
 	}
 	return args
@@ -697,7 +721,7 @@ func (c *Command) Find(args []string) (*Command, []string, error) {
 
 		cmd := c.findNext(nextSubCmd)
 		if cmd != nil {
-			return innerfind(cmd, argsMinusFirstX(innerArgs, nextSubCmd))
+			return innerfind(cmd, c.argsMinusFirstX(innerArgs, nextSubCmd))
 		}
 		return c, innerArgs
 	}

command_test.go

@@ -2551,3 +2551,92 @@ Use "root child [command] --help" for more information about a command.
 		})
 	}
 }
+
+func TestFind(t *testing.T) {
+	var foo, bar string
+	root := &zulu.Command{
+		Use: "root",
+	}
+	root.PersistentFlags().StringVar(&foo, "foo", "", "", zflag.OptShorthand('f'))
+	root.PersistentFlags().StringVar(&bar, "bar", "something", "", zflag.OptShorthand('b'))
+
+	child := &zulu.Command{
+		Use: "child",
+	}
+	root.AddCommand(child)
+
+	testCases := []struct {
+		args              []string
+		expectedFoundArgs []string
+	}{
+		{
+			[]string{"child"},
+			[]string{},
+		},
+		{
+			[]string{"child", "child"},
+			[]string{"child"},
+		},
+		{
+			[]string{"child", "foo", "child", "bar", "child", "baz", "child"},
+			[]string{"foo", "child", "bar", "child", "baz", "child"},
+		},
+		{
+			[]string{"-f", "child", "child"},
+			[]string{"-f", "child"},
+		},
+		{
+			[]string{"child", "-f", "child"},
+			[]string{"-f", "child"},
+		},
+		{
+			[]string{"-b", "child", "child"},
+			[]string{"-b", "child"},
+		},
+		{
+			[]string{"child", "-b", "child"},
+			[]string{"-b", "child"},
+		},
+		{
+			[]string{"child", "-b"},
+			[]string{"-b"},
+		},
+		{
+			[]string{"-b", "-f", "child", "child"},
+			[]string{"-b", "-f", "child"},
+		},
+		{
+			[]string{"-f", "child", "-b", "something", "child"},
+			[]string{"-f", "child", "-b", "something"},
+		},
+		{
+			[]string{"-f", "child", "child", "-b"},
+			[]string{"-f", "child", "-b"},
+		},
+		{
+			[]string{"-f=child", "-b=something", "child"},
+			[]string{"-f=child", "-b=something"},
+		},
+		{
+			[]string{"--foo", "child", "--bar", "something", "child"},
+			[]string{"--foo", "child", "--bar", "something"},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(fmt.Sprintf("%v", tc.args), func(t *testing.T) {
+			cmd, foundArgs, err := root.Find(tc.args)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if cmd != child {
+				t.Fatal("Expected cmd to be child, but it was not")
+			}
+
+			if !reflect.DeepEqual(tc.expectedFoundArgs, foundArgs) {
+				t.Fatalf("Wrong args\nExpected: %v\nGot: %v", tc.expectedFoundArgs, foundArgs)
+			}
+		})
+	}
+}