tailscale/util/ctxkey/key_test.go
Joe Tsai c25968e1c5
all: make use of ctxkey everywhere (#10846)
Also perform minor cleanups on the ctxkey package itself.
Provide guidance on when to use ctxkey.Key[T] over ctxkey.New.
Also, allow for interface kinds because the value wrapping trick
also happens to fix edge cases with interfaces in Go.

Updates #cleanup

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2024-01-16 13:56:23 -08:00

105 lines
3.5 KiB
Go

// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
package ctxkey
import (
"context"
"fmt"
"io"
"regexp"
"testing"
"time"
qt "github.com/frankban/quicktest"
)
func TestKey(t *testing.T) {
c := qt.New(t)
ctx := context.Background()
// Test keys with the same name as being distinct.
k1 := New("same.Name", "")
c.Assert(k1.String(), qt.Equals, "same.Name")
k2 := New("same.Name", "")
c.Assert(k2.String(), qt.Equals, "same.Name")
c.Assert(k1 == k2, qt.Equals, false)
ctx = k1.WithValue(ctx, "hello")
c.Assert(k1.Has(ctx), qt.Equals, true)
c.Assert(k1.Value(ctx), qt.Equals, "hello")
c.Assert(k2.Has(ctx), qt.Equals, false)
c.Assert(k2.Value(ctx), qt.Equals, "")
ctx = k2.WithValue(ctx, "goodbye")
c.Assert(k1.Has(ctx), qt.Equals, true)
c.Assert(k1.Value(ctx), qt.Equals, "hello")
c.Assert(k2.Has(ctx), qt.Equals, true)
c.Assert(k2.Value(ctx), qt.Equals, "goodbye")
// Test default value.
k3 := New("mapreduce.Timeout", time.Hour)
c.Assert(k3.Has(ctx), qt.Equals, false)
c.Assert(k3.Value(ctx), qt.Equals, time.Hour)
ctx = k3.WithValue(ctx, time.Minute)
c.Assert(k3.Has(ctx), qt.Equals, true)
c.Assert(k3.Value(ctx), qt.Equals, time.Minute)
// Test incomparable value.
k4 := New("slice", []int(nil))
c.Assert(k4.Has(ctx), qt.Equals, false)
c.Assert(k4.Value(ctx), qt.DeepEquals, []int(nil))
ctx = k4.WithValue(ctx, []int{1, 2, 3})
c.Assert(k4.Has(ctx), qt.Equals, true)
c.Assert(k4.Value(ctx), qt.DeepEquals, []int{1, 2, 3})
// Accessors should be allocation free.
c.Assert(testing.AllocsPerRun(100, func() {
k1.Value(ctx)
k1.Has(ctx)
k1.ValueOk(ctx)
}), qt.Equals, 0.0)
// Test keys that are created without New.
var k5 Key[string]
c.Assert(k5.String(), qt.Equals, "string")
c.Assert(k1 == k5, qt.Equals, false) // should be different from key created by New
c.Assert(k5.Has(ctx), qt.Equals, false)
ctx = k5.WithValue(ctx, "fizz")
c.Assert(k5.Value(ctx), qt.Equals, "fizz")
var k6 Key[string]
c.Assert(k6.String(), qt.Equals, "string")
c.Assert(k5 == k6, qt.Equals, true)
c.Assert(k6.Has(ctx), qt.Equals, true)
ctx = k6.WithValue(ctx, "fizz")
// Test interface value types.
var k7 Key[any]
c.Assert(k7.Has(ctx), qt.Equals, false)
ctx = k7.WithValue(ctx, "whatever")
c.Assert(k7.Value(ctx), qt.DeepEquals, "whatever")
ctx = k7.WithValue(ctx, []int{1, 2, 3})
c.Assert(k7.Value(ctx), qt.DeepEquals, []int{1, 2, 3})
ctx = k7.WithValue(ctx, nil)
c.Assert(k7.Has(ctx), qt.Equals, true)
c.Assert(k7.Value(ctx), qt.DeepEquals, nil)
k8 := New[error]("error", io.EOF)
c.Assert(k8.Has(ctx), qt.Equals, false)
c.Assert(k8.Value(ctx), qt.Equals, io.EOF)
ctx = k8.WithValue(ctx, nil)
c.Assert(k8.Value(ctx), qt.Equals, nil)
c.Assert(k8.Has(ctx), qt.Equals, true)
err := fmt.Errorf("read error: %w", io.ErrUnexpectedEOF)
ctx = k8.WithValue(ctx, err)
c.Assert(k8.Value(ctx), qt.Equals, err)
c.Assert(k8.Has(ctx), qt.Equals, true)
}
func TestStringer(t *testing.T) {
t.SkipNow() // TODO(https://go.dev/cl/555697): Enable this after fix is merged upstream.
c := qt.New(t)
ctx := context.Background()
c.Assert(fmt.Sprint(New("foo.Bar", "").WithValue(ctx, "baz")), qt.Matches, regexp.MustCompile("foo.Bar.*baz"))
c.Assert(fmt.Sprint(New("", []int{}).WithValue(ctx, []int{1, 2, 3})), qt.Matches, regexp.MustCompile(fmt.Sprintf("%[1]T.*%[1]v", []int{1, 2, 3})))
c.Assert(fmt.Sprint(New("", 0).WithValue(ctx, 5)), qt.Matches, regexp.MustCompile("int.*5"))
c.Assert(fmt.Sprint(Key[time.Duration]{}.WithValue(ctx, time.Hour)), qt.Matches, regexp.MustCompile(fmt.Sprintf("%[1]T.*%[1]v", time.Hour)))
}