Copied mongo repo (to patch it)

mongo/tag/tag.go

@@ -0,0 +1,80 @@
+// Copyright (C) MongoDB, Inc. 2017-present.
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License. You may obtain
+// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+
+// Package tag provides a way to define filters for tagged servers.
+package tag // import "go.mongodb.org/mongo-driver/tag"
+
+import (
+	"bytes"
+	"fmt"
+)
+
+// Tag is a name/vlaue pair.
+type Tag struct {
+	Name  string
+	Value string
+}
+
+// String returns a human-readable human-readable description of the tag.
+func (tag Tag) String() string {
+	return fmt.Sprintf("%s=%s", tag.Name, tag.Value)
+}
+
+// NewTagSetFromMap creates a new tag set from a map.
+func NewTagSetFromMap(m map[string]string) Set {
+	var set Set
+	for k, v := range m {
+		set = append(set, Tag{Name: k, Value: v})
+	}
+
+	return set
+}
+
+// NewTagSetsFromMaps creates new tag sets from maps.
+func NewTagSetsFromMaps(maps []map[string]string) []Set {
+	sets := make([]Set, 0, len(maps))
+	for _, m := range maps {
+		sets = append(sets, NewTagSetFromMap(m))
+	}
+	return sets
+}
+
+// Set is an ordered list of Tags.
+type Set []Tag
+
+// Contains indicates whether the name/value pair exists in the tagset.
+func (ts Set) Contains(name, value string) bool {
+	for _, t := range ts {
+		if t.Name == name && t.Value == value {
+			return true
+		}
+	}
+
+	return false
+}
+
+// ContainsAll indicates whether all the name/value pairs exist in the tagset.
+func (ts Set) ContainsAll(other []Tag) bool {
+	for _, ot := range other {
+		if !ts.Contains(ot.Name, ot.Value) {
+			return false
+		}
+	}
+
+	return true
+}
+
+// String returns a human-readable human-readable description of the tagset.
+func (ts Set) String() string {
+	var b bytes.Buffer
+	for i, tag := range ts {
+		if i > 0 {
+			b.WriteString(",")
+		}
+		b.WriteString(tag.String())
+	}
+	return b.String()
+}

mongo/tag/tag_test.go

@@ -0,0 +1,96 @@
+// Copyright (C) MongoDB, Inc. 2017-present.
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License. You may obtain
+// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+
+package tag
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"go.mongodb.org/mongo-driver/internal/testutil/assert"
+)
+
+func TestTag_String(t *testing.T) {
+	t.Parallel()
+
+	tag := Tag{Name: "a", Value: "1"}
+	assert.Equal(t, "a=1", tag.String(), `expected "a=1", got %q`, tag.String())
+}
+
+func TestTagSets_NewTagSet(t *testing.T) {
+	t.Parallel()
+
+	ts := Set{Tag{Name: "a", Value: "1"}}
+
+	require.True(t, ts.Contains("a", "1"))
+	require.False(t, ts.Contains("1", "a"))
+	require.False(t, ts.Contains("A", "1"))
+	require.False(t, ts.Contains("a", "10"))
+}
+
+func TestTagSets_NewTagSetFromMap(t *testing.T) {
+	t.Parallel()
+
+	ts := NewTagSetFromMap(map[string]string{"a": "1"})
+
+	require.True(t, ts.Contains("a", "1"))
+	require.False(t, ts.Contains("1", "a"))
+	require.False(t, ts.Contains("A", "1"))
+	require.False(t, ts.Contains("a", "10"))
+}
+
+func TestTagSets_NewTagSetsFromMaps(t *testing.T) {
+	t.Parallel()
+
+	tss := NewTagSetsFromMaps([]map[string]string{{"a": "1"}, {"b": "1"}})
+
+	require.Len(t, tss, 2)
+
+	ts := tss[0]
+	require.True(t, ts.Contains("a", "1"))
+	require.False(t, ts.Contains("1", "a"))
+	require.False(t, ts.Contains("A", "1"))
+	require.False(t, ts.Contains("a", "10"))
+
+	ts = tss[1]
+	require.True(t, ts.Contains("b", "1"))
+	require.False(t, ts.Contains("1", "b"))
+	require.False(t, ts.Contains("B", "1"))
+	require.False(t, ts.Contains("b", "10"))
+}
+
+func TestTagSets_ContainsAll(t *testing.T) {
+	t.Parallel()
+
+	ts := Set{
+		Tag{Name: "a", Value: "1"},
+		Tag{Name: "b", Value: "2"},
+	}
+
+	test := Set{Tag{Name: "a", Value: "1"}}
+	require.True(t, ts.ContainsAll(test))
+	test = Set{Tag{Name: "a", Value: "1"}, Tag{Name: "b", Value: "2"}}
+	require.True(t, ts.ContainsAll(test))
+	test = Set{Tag{Name: "a", Value: "1"}, Tag{Name: "b", Value: "2"}}
+	require.True(t, ts.ContainsAll(test))
+
+	test = Set{Tag{Name: "a", Value: "2"}, Tag{Name: "b", Value: "1"}}
+	require.False(t, ts.ContainsAll(test))
+	test = Set{Tag{Name: "a", Value: "1"}, Tag{Name: "b", Value: "1"}}
+	require.False(t, ts.ContainsAll(test))
+	test = Set{Tag{Name: "a", Value: "2"}, Tag{Name: "b", Value: "2"}}
+	require.False(t, ts.ContainsAll(test))
+}
+
+func TestTagSets_String(t *testing.T) {
+	t.Parallel()
+
+	ts := Set{
+		Tag{Name: "a", Value: "1"},
+		Tag{Name: "b", Value: "2"},
+	}
+	assert.Equal(t, "a=1,b=2", ts.String(), `expected "a=1,b=2", got %q`, ts.String())
+}