Add support to short form with equal sign: -p=value

flag.go

diff --git a/flag.go b/flag.go
index 5dc5373..c43edad 100644
--- a/flag.go
+++ b/flag.go
@@ -141,12 +141,12 @@
 
 // A Flag represents the state of a flag.
 type Flag struct {
-	Name      string // name as it appears on command line
-	Shorthand string // one-letter abbreviated flag
-	Usage     string // help message
-	Value     Value  // value as set
-	DefValue  string // default value (as text); for usage message
-	Changed   bool   // If the user set the value (or if left to default)
+	Name        string              // name as it appears on command line
+	Shorthand   string              // one-letter abbreviated flag
+	Usage       string              // help message
+	Value       Value               // value as set
+	DefValue    string              // default value (as text); for usage message
+	Changed     bool                // If the user set the value (or if left to default)
 	Annotations map[string][]string // used by cobra.Command  bash autocomple code
 }
 
@@ -507,7 +507,8 @@
 				continue
 			}
 			if i < len(shorthands)-1 {
-				if e := f.setFlag(flag, shorthands[i+1:], s); e != nil {
+				v := strings.TrimPrefix(shorthands[i+1:], "=")
+				if e := f.setFlag(flag, v, s); e != nil {
 					err = e
 					return
 				}
@@ -554,7 +555,7 @@
 			args, err = f.parseShortArg(s, args)
 		}
 		if err != nil {
-		   return
+			return
 		}
 	}
 	return

flag_test.go

diff --git a/flag_test.go b/flag_test.go
index a33c601..d6aa308 100644
--- a/flag_test.go
+++ b/flag_test.go
@@ -185,7 +185,8 @@
 	boolaFlag := f.BoolP("boola", "a", false, "bool value")
 	boolbFlag := f.BoolP("boolb", "b", false, "bool2 value")
 	boolcFlag := f.BoolP("boolc", "c", false, "bool3 value")
-	stringFlag := f.StringP("string", "s", "0", "string value")
+	stringaFlag := f.StringP("stringa", "s", "0", "string value")
+	stringzFlag := f.StringP("stringz", "z", "0", "string value")
 	extra := "interspersed-argument"
 	notaflag := "--i-look-like-a-flag"
 	args := []string{
@@ -193,6 +194,7 @@
 		extra,
 		"-cs",
 		"hello",
+		"-z=something",
 		"--",
 		notaflag,
 	}
@@ -212,8 +214,11 @@
 	if *boolcFlag != true {
 		t.Error("boolc flag should be true, is ", *boolcFlag)
 	}
-	if *stringFlag != "hello" {
-		t.Error("string flag should be `hello`, is ", *stringFlag)
+	if *stringaFlag != "hello" {
+		t.Error("stringa flag should be `hello`, is ", *stringaFlag)
+	}
+	if *stringzFlag != "something" {
+		t.Error("stringz flag should be `something`, is ", *stringzFlag)
 	}
 	if len(f.Args()) != 2 {
 		t.Error("expected one argument, got", len(f.Args()))