pkg/expect: ExpectFunc, LineCount

ExpectFunc to make expect more extensible. LineCount to be
able to check 'no output' command.

pkg/expect/expect_test.go

@@ -18,6 +18,24 @@ package expect
 
 import "testing"
 
+func TestExpectFunc(t *testing.T) {
+	ep, err := NewExpect("/bin/echo", "hello world")
+	if err != nil {
+		t.Fatal(err)
+	}
+	wstr := "hello world\r\n"
+	l, eerr := ep.ExpectFunc(func(a string) bool { return len(a) > 10 })
+	if eerr != nil {
+		t.Fatal(eerr)
+	}
+	if l != wstr {
+		t.Fatalf(`got "%v", expected "%v"`, l, wstr)
+	}
+	if cerr := ep.Close(); cerr != nil {
+		t.Fatal(cerr)
+	}
+}
+
 func TestEcho(t *testing.T) {
 	ep, err := NewExpect("/bin/echo", "hello world")
 	if err != nil {
@@ -39,6 +57,27 @@ func TestEcho(t *testing.T) {
 	}
 }
 
+func TestLineCount(t *testing.T) {
+	ep, err := NewExpect("/usr/bin/printf", "1\n2\n3")
+	if err != nil {
+		t.Fatal(err)
+	}
+	wstr := "3"
+	l, eerr := ep.Expect(wstr)
+	if eerr != nil {
+		t.Fatal(eerr)
+	}
+	if l != wstr {
+		t.Fatalf(`got "%v", expected "%v"`, l, wstr)
+	}
+	if ep.LineCount() != 3 {
+		t.Fatalf("got %d, expected 3", ep.LineCount())
+	}
+	if cerr := ep.Close(); cerr != nil {
+		t.Fatal(cerr)
+	}
+}
+
 func TestSend(t *testing.T) {
 	ep, err := NewExpect("/usr/bin/tr", "a", "b")
 	if err != nil {