From 3984353d3712fd9ab5833d58b371323021c12f52 Mon Sep 17 00:00:00 2001
From: Pavel Karpy <carpawell@nspcc.ru>
Date: Tue, 8 Jun 2021 15:33:42 +0300
Subject: [PATCH] [#302] pkg/container: Document default values set in
 `NewAttribute`

Document field values of instance constructed via `NewAttribute`.
Assert the values in corresponding unit test.

Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>
---
 pkg/container/attribute.go      |  5 +++++
 pkg/container/attribute_test.go | 13 +++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/pkg/container/attribute.go b/pkg/container/attribute.go
index 8964a048..2e4492fe 100644
--- a/pkg/container/attribute.go
+++ b/pkg/container/attribute.go
@@ -9,6 +9,11 @@ type (
 	Attributes []*Attribute
 )
 
+// NewAttribute creates and initializes blank Attribute.
+//
+// Defaults:
+//  - key: "";
+//  - value: "".
 func NewAttribute() *Attribute {
 	return NewAttributeFromV2(new(container.Attribute))
 }
diff --git a/pkg/container/attribute_test.go b/pkg/container/attribute_test.go
index ea232867..e32dfda6 100644
--- a/pkg/container/attribute_test.go
+++ b/pkg/container/attribute_test.go
@@ -15,6 +15,19 @@ func TestAttribute(t *testing.T) {
 		require.Nil(t, x.ToV2())
 	})
 
+	t.Run("default values", func(t *testing.T) {
+		attr := container.NewAttribute()
+
+		// check initial values
+		require.Empty(t, attr.Key())
+		require.Empty(t, attr.Value())
+
+		// convert to v2 message
+		attrV2 := attr.ToV2()
+		require.Empty(t, attrV2.GetKey())
+		require.Empty(t, attrV2.GetValue())
+	})
+
 	const (
 		key   = "key"
 		value = "value"