From 70d56b6986edbb57065dd9918db6d46fffabce41 Mon Sep 17 00:00:00 2001
From: Justin Ruggles <justinr@vimeo.com>
Date: Sat, 9 May 2020 08:39:40 -0400
Subject: [PATCH] Allow colons in values for map fields

A common use case for this is putting a URL in a map value.
---
 envconfig.go               | 2 +-
 envconfig_test.go          | 9 +++++++++
 testdata/custom.txt        | 1 +
 testdata/default_list.txt  | 5 +++++
 testdata/default_table.txt | 1 +
 testdata/fault.txt         | 1 +
 6 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/envconfig.go b/envconfig.go
index 3f16108..0d01e70 100644
--- a/envconfig.go
+++ b/envconfig.go
@@ -321,7 +321,7 @@ func processField(value string, field reflect.Value) error {
 		if len(strings.TrimSpace(value)) != 0 {
 			pairs := strings.Split(value, ",")
 			for _, pair := range pairs {
-				kvpair := strings.Split(pair, ":")
+				kvpair := strings.SplitN(pair, ":", 2)
 				if len(kvpair) != 2 {
 					return fmt.Errorf("invalid map item: %q", pair)
 				}
diff --git a/envconfig_test.go b/envconfig_test.go
index 2ca765d..103c02c 100644
--- a/envconfig_test.go
+++ b/envconfig_test.go
@@ -70,6 +70,7 @@ type Specification struct {
 	MapField     map[string]string `default:"one:two,three:four"`
 	UrlValue     CustomURL
 	UrlPointer   *CustomURL
+	MapFieldWithColon map[string]string
 }
 
 type Embedded struct {
@@ -111,6 +112,7 @@ func TestProcess(t *testing.T) {
 	os.Setenv("ENV_CONFIG_MULTI_WORD_ACR_WITH_AUTO_SPLIT", "25")
 	os.Setenv("ENV_CONFIG_URLVALUE", "https://github.com/kelseyhightower/envconfig")
 	os.Setenv("ENV_CONFIG_URLPOINTER", "https://github.com/kelseyhightower/envconfig")
+	os.Setenv("ENV_CONFIG_MAPFIELDWITHCOLON", "name:envconfig,url:https://github.com/kelseyhightower/envconfig")
 	err := Process("env_config", &s)
 	if err != nil {
 		t.Error(err.Error())
@@ -217,6 +219,13 @@ func TestProcess(t *testing.T) {
 	if *s.UrlPointer.Value != *u {
 		t.Errorf("expected %q, got %q", u, s.UrlPointer.Value.String())
 	}
+
+	if s.MapFieldWithColon["name"] != "envconfig" {
+		t.Errorf("expected %q, got %q", "envconfig", s.MapFieldWithColon["name"])
+	}
+	if s.MapFieldWithColon["url"] != "https://github.com/kelseyhightower/envconfig" {
+		t.Errorf("expected %q, got %q", "https://github.com/kelseyhightower/envconfig", s.MapFieldWithColon["url"])
+	}
 }
 
 func TestParseErrorBool(t *testing.T) {
diff --git a/testdata/custom.txt b/testdata/custom.txt
index 04d2f5d..5dd2c97 100644
--- a/testdata/custom.txt
+++ b/testdata/custom.txt
@@ -34,3 +34,4 @@ ENV_CONFIG_DATETIME=
 ENV_CONFIG_MAPFIELD=
 ENV_CONFIG_URLVALUE=
 ENV_CONFIG_URLPOINTER=
+ENV_CONFIG_MAPFIELDWITHCOLON=
diff --git a/testdata/default_list.txt b/testdata/default_list.txt
index fb0eced..2242406 100644
--- a/testdata/default_list.txt
+++ b/testdata/default_list.txt
@@ -181,3 +181,8 @@ ENV_CONFIG_URLPOINTER
 ..[type]........CustomURL
 ..[default].....
 ..[required]....
+ENV_CONFIG_MAPFIELDWITHCOLON
+..[description].
+..[type]........Comma-separated.list.of.String:String.pairs
+..[default].....
+..[required]....
diff --git a/testdata/default_table.txt b/testdata/default_table.txt
index 65c9b44..d0a4280 100644
--- a/testdata/default_table.txt
+++ b/testdata/default_table.txt
@@ -38,3 +38,4 @@ ENV_CONFIG_DATETIME..............................Time...........................
 ENV_CONFIG_MAPFIELD..............................Comma-separated.list.of.String:String.pairs.....one:two,three:four................
 ENV_CONFIG_URLVALUE..............................CustomURL.........................................................................
 ENV_CONFIG_URLPOINTER............................CustomURL.........................................................................
+ENV_CONFIG_MAPFIELDWITHCOLON.....................Comma-separated.list.of.String:String.pairs.......................................
diff --git a/testdata/fault.txt b/testdata/fault.txt
index b525ff1..4d74596 100644
--- a/testdata/fault.txt
+++ b/testdata/fault.txt
@@ -34,3 +34,4 @@
 {.Key}
 {.Key}
 {.Key}
+{.Key}