internal/ini: Normalize Section keys to lowercase

CHANGELOG_PENDING.md

@@ -21,6 +21,8 @@ SDK Features
 
 SDK Enhancements
 ---
+* `internal/ini`: Normalize Section keys to lowercase ([#495](https://github.com/aws/aws-sdk-go-v2/pull/495))
+  * Update's SDK's ini utility to store all keys as lowercase. This brings the SDK inline with the AWS CLI's behavior.
 
 SDK Bugs
 ---

aws/external/shared_config_test.go

@@ -335,6 +335,16 @@ func TestLoadSharedConfigFromFile(t *testing.T) {
 				Err:      nil,
 			},
 		},
+		{
+			Profile:   "with_mixed_case_keys",
+			Expected: SharedConfig{
+				Credentials: aws.Credentials{
+					AccessKeyID:     "accessKey",
+					SecretAccessKey: "secret",
+					Source:          fmt.Sprintf("SharedConfigCredentials: %s", testConfigFilename),
+				},
+			},
+		},
 	}
 
 	for i, c := range cases {

aws/external/testdata/shared_config

@@ -84,6 +84,11 @@ s3_use_arn_region=true
 [endpoint_discovery]
 endpoint_discovery_enabled=true
 
+
+[with_mixed_case_keys]
+aWs_AcCeSs_kEy_ID = accessKey
+aWs_SecrEt_AccEsS_kEY = secret
+
 [assume_role_with_credential_source]
 role_arn = assume_role_with_credential_source_role_arn
 credential_source = Ec2InstanceMetadata

internal/ini/testdata/valid/mixed_case_keys

@@ -0,0 +1,4 @@
+[with_mixed_case_keys]
+sTring_Value = secret
+iNt_Value = 60
+flOAt_Value = 12.3

internal/ini/testdata/valid/mixed_case_keys_expected

@@ -0,0 +1,7 @@
+{
+	"with_mixed_case_keys": {
+		"int_value": 60,
+		"string_value": "secret",
+		"float_value": 12.3
+	}
+}

internal/ini/testdata/valid/utf_8_profile_expected

@@ -1,6 +1,6 @@
 {
 	"ʃʉʍΡιξ": {
-		"ϰϪϧ": "Ϯϴϖ",
+		"ϰϫϧ": "Ϯϴϖ",
 		"ϝϧ": "ϟΞ΅"
 	}
 }

internal/ini/visitor.go

@@ -3,6 +3,7 @@ package ini
 import (
 	"fmt"
 	"sort"
+	"strings"
 )
 
 // Visitor is an interface used by walkers that will
@@ -60,7 +61,7 @@ func (v *DefaultVisitor) VisitExpr(expr AST) error {
 				return err
 			}
 
-			t.values[key] = v
+			t.values[strings.ToLower(key)] = v
 		default:
 			return NewParseError(fmt.Sprintf("unsupported expression %v", expr))
 		}