integration-cli: fix TestAttachDetach, rm TestAttachDetachTruncatedID

It looks like the logic of the test became wrong after commit
ae0883c ("Move TestAttachDetach to integration-cli").

The original logic was:
* (a few first steps skipped for clarity)
* send escape sequence to "attach";
* check "attach" is exiting (i.e. escape sequence works);
* check the container is still alive;
* kill the container.

Also, timeouts were big at that time, in the order of seconds.

The logic after the above mentioned commit and until now is:
* ...
* send escape sequence to "attach";
* check the container is running (why shouldn't it?);
* kill the container;
* checks that the "attach" has exited.

So, from the "let's check detach using escape sequence is working"
the test became something like "let's check that attach is gone
once we kill the container".

Let's fix the above test, also increasing the timeout waiting
for attach to exit (which fails from time to time on power CI).

Now, the second test, TestAttachDetachTruncatedID, does the exact
same thing, except it uses a truncated container ID. It does not
seem to be of much value, so let's remove it.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

integration-cli/docker_cli_attach_unix_test.go

@@ -10,7 +10,6 @@ import (
 	"time"
 
 	"github.com/docker/docker/integration-cli/checker"
-	"github.com/docker/docker/pkg/stringid"
 	"github.com/go-check/check"
 	"github.com/kr/pty"
 )
@@ -146,7 +145,7 @@ func (s *DockerSuite) TestAttachDetach(c *check.C) {
 	c.Assert(err, check.IsNil)
 	out, err = bufio.NewReader(stdout).ReadString('\n')
 	c.Assert(err, check.IsNil)
-	c.Assert(strings.TrimSpace(out), checker.Equals, "hello", check.Commentf("expected 'hello', got %q", out))
+	c.Assert(strings.TrimSpace(out), checker.Equals, "hello")
 
 	// escape sequence
 	_, err = cpty.Write([]byte{16})
@@ -158,72 +157,15 @@ func (s *DockerSuite) TestAttachDetach(c *check.C) {
 	ch := make(chan struct{})
 	go func() {
 		cmd.Wait()
-		ch <- struct{}{}
-	}()
-
-	running := inspectField(c, id, "State.Running")
-	c.Assert(running, checker.Equals, "true", check.Commentf("expected container to still be running"))
-
-	go func() {
-		dockerCmdWithResult("kill", id)
+		close(ch)
 	}()
 
 	select {
 	case <-ch:
-	case <-time.After(10 * time.Millisecond):
+	case <-time.After(1 * time.Second):
 		c.Fatal("timed out waiting for container to exit")
 	}
 
-}
-
-// TestAttachDetachTruncatedID checks that attach in tty mode can be detached
-func (s *DockerSuite) TestAttachDetachTruncatedID(c *check.C) {
-	out, _ := dockerCmd(c, "run", "-itd", "busybox", "cat")
-	id := stringid.TruncateID(strings.TrimSpace(out))
-	c.Assert(waitRun(id), check.IsNil)
-
-	cpty, tty, err := pty.Open()
-	c.Assert(err, checker.IsNil)
-	defer cpty.Close()
-
-	cmd := exec.Command(dockerBinary, "attach", id)
-	cmd.Stdin = tty
-	stdout, err := cmd.StdoutPipe()
-	c.Assert(err, checker.IsNil)
-	defer stdout.Close()
-	err = cmd.Start()
-	c.Assert(err, checker.IsNil)
-
-	_, err = cpty.Write([]byte("hello\n"))
-	c.Assert(err, checker.IsNil)
-	out, err = bufio.NewReader(stdout).ReadString('\n')
-	c.Assert(err, checker.IsNil)
-	c.Assert(strings.TrimSpace(out), checker.Equals, "hello", check.Commentf("expected 'hello', got %q", out))
-
-	// escape sequence
-	_, err = cpty.Write([]byte{16})
-	c.Assert(err, checker.IsNil)
-	time.Sleep(100 * time.Millisecond)
-	_, err = cpty.Write([]byte{17})
-	c.Assert(err, checker.IsNil)
-
-	ch := make(chan struct{})
-	go func() {
-		cmd.Wait()
-		ch <- struct{}{}
-	}()
-
 	running := inspectField(c, id, "State.Running")
-	c.Assert(running, checker.Equals, "true", check.Commentf("expected container to still be running"))
-
-	go func() {
-		dockerCmdWithResult("kill", id)
-	}()
-
-	select {
-	case <-ch:
-	case <-time.After(10 * time.Millisecond):
-		c.Fatal("timed out waiting for container to exit")
-	}
-
+	c.Assert(running, checker.Equals, "true") // container should be running
 }