bugfix: fix baggage set member failed (#3165)

* fix baggage set member failed

* add unittest

* fix unittest

* rewrite unittest code

baggage/baggage.go

@@ -465,6 +465,7 @@ func (b Baggage) Member(key string) Member {
 		key:        key,
 		value:      v.Value,
 		properties: fromInternalProperties(v.Properties),
+		hasData:    true,
 	}
 }
 
@@ -484,6 +485,7 @@ func (b Baggage) Members() []Member {
 			key:        k,
 			value:      v.Value,
 			properties: fromInternalProperties(v.Properties),
+			hasData:    true,
 		})
 	}
 	return members

baggage/baggage_test.go

@@ -589,6 +589,74 @@ func TestBaggageSetMember(t *testing.T) {
 	assert.Equal(t, 2, len(b4.list))
 }
 
+func TestBaggageSetFalseMember(t *testing.T) {
+	b0 := Baggage{}
+
+	key := "k"
+	m := Member{key: key, hasData: false}
+	b1, err := b0.SetMember(m)
+	assert.Error(t, err)
+	assert.NotContains(t, b0.list, key)
+	assert.Equal(t, baggage.Item{}, b1.list[key])
+	assert.Equal(t, 0, len(b0.list))
+	assert.Equal(t, 0, len(b1.list))
+
+	m.value = "v"
+	b2, err := b1.SetMember(m)
+	assert.Error(t, err)
+	assert.Equal(t, baggage.Item{}, b1.list[key])
+	assert.Equal(t, baggage.Item{Value: ""}, b2.list[key])
+	assert.Equal(t, 0, len(b1.list))
+	assert.Equal(t, 0, len(b2.list))
+}
+
+func TestBaggageSetFalseMembers(t *testing.T) {
+	b0 := Baggage{}
+
+	key := "k"
+	m := Member{key: key, hasData: true}
+	b1, err := b0.SetMember(m)
+	assert.NoError(t, err)
+	assert.NotContains(t, b0.list, key)
+	assert.Equal(t, baggage.Item{}, b1.list[key])
+	assert.Equal(t, 0, len(b0.list))
+	assert.Equal(t, 1, len(b1.list))
+
+	m.value = "v"
+	b2, err := b1.SetMember(m)
+	assert.NoError(t, err)
+	assert.Equal(t, baggage.Item{}, b1.list[key])
+	assert.Equal(t, baggage.Item{Value: "v"}, b2.list[key])
+	assert.Equal(t, 1, len(b1.list))
+	assert.Equal(t, 1, len(b2.list))
+
+	p := properties{{key: "p", hasData: false}}
+	m.properties = p
+	b3, err := b2.SetMember(m)
+	assert.NoError(t, err)
+	assert.Equal(t, baggage.Item{Value: "v"}, b2.list[key])
+	assert.Equal(t, baggage.Item{Value: "v", Properties: []baggage.Property{{Key: "p"}}}, b3.list[key])
+	assert.Equal(t, 1, len(b2.list))
+	assert.Equal(t, 1, len(b3.list))
+
+	// The returned baggage needs to be immutable and should use a copy of the
+	// properties slice.
+	p[0] = Property{key: "different", hasData: false}
+	assert.Equal(t, baggage.Item{Value: "v", Properties: []baggage.Property{{Key: "p"}}}, b3.list[key])
+	// Reset for below.
+	p[0] = Property{key: "p", hasData: false}
+
+	m = Member{key: "another", hasData: false}
+	b4, err := b3.SetMember(m)
+	assert.Error(t, err)
+	assert.Equal(t, baggage.Item{Value: "v", Properties: []baggage.Property{{Key: "p"}}}, b3.list[key])
+	assert.NotContains(t, b3.list, m.key)
+	assert.Equal(t, baggage.Item{Value: "v", Properties: []baggage.Property{{Key: "p"}}}, b4.list[key])
+	assert.Equal(t, baggage.Item{}, b4.list[m.key])
+	assert.Equal(t, 1, len(b3.list))
+	assert.Equal(t, 1, len(b4.list))
+}
+
 func TestNilBaggageMembers(t *testing.T) {
 	assert.Nil(t, Baggage{}.Members())
 }
@@ -602,6 +670,7 @@ func TestBaggageMembers(t *testing.T) {
 				{key: "state", value: "on", hasValue: true},
 				{key: "red"},
 			},
+			hasData: true,
 		},
 		{
 			key:   "bar",
@@ -609,6 +678,7 @@ func TestBaggageMembers(t *testing.T) {
 			properties: properties{
 				{key: "yellow"},
 			},
+			hasData: true,
 		},
 	}
 
@@ -631,7 +701,7 @@ func TestBaggageMembers(t *testing.T) {
 
 func TestBaggageMember(t *testing.T) {
 	bag := Baggage{list: baggage.List{"foo": {Value: "1"}}}
-	assert.Equal(t, Member{key: "foo", value: "1"}, bag.Member("foo"))
+	assert.Equal(t, Member{key: "foo", value: "1", hasData: true}, bag.Member("foo"))
 	assert.Equal(t, Member{}, bag.Member("bar"))
 }