Add HW 3

homework/03-http-server/tests/test_utils.go

@@ -0,0 +1,103 @@
+package hw3test
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"os"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+// TC implements *testing.T and context.Context at the same time.
+// Also has some helper methods.
+type TC struct {
+	*testing.T
+	ctx context.Context
+}
+
+func NewTestContext(t *testing.T) *TC {
+	return &TC{
+		ctx: context.Background(),
+		T:   t,
+	}
+}
+
+func (tc *TC) Errorf(format string, args ...any) {
+	str := fmt.Sprintf(format, args...)
+	if strings.HasPrefix(str, "\n\tError Trace:") {
+		_, after, ok := strings.Cut(str, "\tError:")
+		if ok {
+			str = "\n\tError:" + after
+		}
+	}
+	Error(tc, str)
+	tc.T.Errorf(str)
+}
+
+func (tc *TC) RunByName(name string, f func(*TC)) bool {
+	return tc.Run(name, func(t *testing.T) {
+		f(tc.derive(t))
+	})
+}
+
+func (tc *TC) RunBySeed(seed int64, f func(*TC)) bool {
+	return tc.Run(strconv.FormatInt(seed, 10), func(t *testing.T) {
+		f(tc.derive(t))
+	})
+}
+
+func (tc *TC) Done() <-chan struct{} {
+	return tc.ctx.Done()
+}
+
+func (tc *TC) Err() error {
+	return tc.ctx.Err()
+}
+
+func (tc *TC) Value(key any) any {
+	return tc.ctx.Value(key)
+}
+
+// derive copies *TC and replaces *testing.T
+func (tc TC) derive(t *testing.T) *TC {
+	tc.T = t
+	return &tc
+}
+
+// Get bool from envvars
+func boolFromEnv(key string, def bool) bool {
+	value := os.Getenv(key)
+	if value == "" {
+		return def
+	}
+
+	value = strings.ToLower(value)
+	switch value {
+	case "t":
+		return true
+	case "true":
+		return true
+	case "y":
+		return true
+	case "yes":
+		return true
+	}
+	return false
+}
+
+// GetFreePort asks the kernel for a free open port that is ready to use.
+func GetFreePort() (int, error) {
+	addr, err := net.ResolveTCPAddr("tcp", "localhost:0")
+	if err != nil {
+		return 0, err
+	}
+
+	l, err := net.ListenTCP("tcp", addr)
+	if err != nil {
+		return 0, err
+	}
+	defer l.Close()
+	return l.Addr().(*net.TCPAddr).Port, nil
+}