From b49cf25e976b8ae1b83f004f2d9755f9e733ec13 Mon Sep 17 00:00:00 2001
From: Sebastien Lavoie <sebastien.lavoie@shopify.com>
Date: Fri, 27 Aug 2021 11:36:20 -0400
Subject: [PATCH] Add ToHeaderField

---
 strcase/id.go      |  5 +++++
 strcase/id_test.go | 13 +++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/strcase/id.go b/strcase/id.go
index e9e5402..a120c15 100644
--- a/strcase/id.go
+++ b/strcase/id.go
@@ -41,6 +41,11 @@ func ToSnakeCase(input string) string {
 	return SplitJoin(input, CaseStrategyNever, '_', false)
 }
 
+// ToHeaderField transforms a string in any form to An-HTTP-Header.
+func ToHeaderField(input string) string {
+	return SplitJoin(input, CaseStrategyTitle, '-', true)
+}
+
 func SplitJoin(input string, caseStrategy CaseStrategy, separator rune, initialism bool) string {
 	firstUpper := int(caseStrategy)
 	b := allocateBuilder(input, separator)
diff --git a/strcase/id_test.go b/strcase/id_test.go
index bb23e47..1bb29b2 100644
--- a/strcase/id_test.go
+++ b/strcase/id_test.go
@@ -106,6 +106,7 @@ func Test_splitJoin(t *testing.T) {
 		pascal   string
 		pascalGo string
 		snake    string
+		header   string
 	}{
 		{
 			// everything empty
@@ -115,30 +116,35 @@ func Test_splitJoin(t *testing.T) {
 			pascal: "A",
 			camel:  "a",
 			snake:  "a",
+			header: "A",
 		},
 		{
 			input:  "A",
 			pascal: "A",
 			camel:  "a",
 			snake:  "a",
+			header: "A",
 		},
 		{
 			input:  "a_a",
 			pascal: "AA",
 			camel:  "aA",
 			snake:  "a_a",
+			header: "A-A",
 		},
 		{
 			input:  "__a___a_",
 			pascal: "AA",
 			camel:  "aA",
 			snake:  "a_a",
+			header: "A-A",
 		},
 		{
 			input:  "aa_bbb",
 			pascal: "AaBbb",
 			camel:  "aaBbb",
 			snake:  "aa_bbb",
+			header: "Aa-Bbb",
 		},
 		{
 			input:    "aa_id",
@@ -147,18 +153,21 @@ func Test_splitJoin(t *testing.T) {
 			camel:    "aaId",
 			camelGo:  "aaID",
 			snake:    "aa_id",
+			header:   "Aa-ID",
 		},
 		{
 			input:  "fooBar",
 			pascal: "FooBar",
 			camel:  "fooBar",
 			snake:  "foo_bar",
+			header: "Foo-Bar",
 		},
 		{
 			input:  "FooBAR",
 			pascal: "FooBar",
 			camel:  "fooBar",
 			snake:  "foo_bar",
+			header: "Foo-Bar",
 		},
 		{
 			input:    "fooUrl",
@@ -167,6 +176,7 @@ func Test_splitJoin(t *testing.T) {
 			camel:    "fooUrl",
 			camelGo:  "fooURL",
 			snake:    "foo_url",
+			header:   "Foo-URL",
 		},
 		{
 			input:    "fooURL",
@@ -175,6 +185,7 @@ func Test_splitJoin(t *testing.T) {
 			camel:    "fooUrl",
 			camelGo:  "fooURL",
 			snake:    "foo_url",
+			header:   "Foo-URL",
 		},
 		{
 			input:    "url10",
@@ -182,6 +193,7 @@ func Test_splitJoin(t *testing.T) {
 			pascalGo: "URL10",
 			camel:    "url10",
 			snake:    "url_10",
+			header:   "URL-10",
 		},
 		{
 			input:    "url_id",
@@ -190,6 +202,7 @@ func Test_splitJoin(t *testing.T) {
 			camel:    "urlId",
 			camelGo:  "urlID",
 			snake:    "url_id",
+			header:   "URL-ID",
 		},
 	}
 	for _, tt := range tests {