1 files changed, 87 insertions, 0 deletions
diff --git a/internal/pktline/pktline_test.go b/internal/pktline/pktline_test.go
new file mode 100644
index 0000000..cf3f6fd
--- /dev/null
+++ b/internal/pktline/pktline_test.go
@@ -0,0 +1,87 @@
+package pktline
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+var (
+	largestString = strings.Repeat("z", 0xffff-4)
+)
+
+func TestScanner(t *testing.T) {
+	largestPacket := "ffff" + largestString
+	testCases := []struct {
+		desc string
+		in   string
+		out  []string
+		fail bool
+	}{
+		{
+			desc: "happy path",
+			in:   "0010hello world!000000010010hello world!",
+			out:  []string{"0010hello world!", "0000", "0001", "0010hello world!"},
+		},
+		{
+			desc: "large input",
+			in:   "0010hello world!0000" + largestPacket + "0000",
+			out:  []string{"0010hello world!", "0000", largestPacket, "0000"},
+		},
+		{
+			desc: "missing byte middle",
+			in:   "0010hello world!00000010010hello world!",
+			out:  []string{"0010hello world!", "0000", "0010010hello wor"},
+			fail: true,
+		},
+		{
+			desc: "unfinished prefix",
+			in:   "0010hello world!000",
+			out:  []string{"0010hello world!"},
+			fail: true,
+		},
+		{
+			desc: "short read in data, only prefix",
+			in:   "0010hello world!0005",
+			out:  []string{"0010hello world!"},
+			fail: true,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.desc, func(t *testing.T) {
+			scanner := NewScanner(strings.NewReader(tc.in))
+			var output []string
+			for scanner.Scan() {
+				output = append(output, scanner.Text())
+			}
+
+			if tc.fail {
+				require.Error(t, scanner.Err())
+			} else {
+				require.NoError(t, scanner.Err())
+			}
+
+			require.Equal(t, tc.out, output)
+		})
+	}
+}
+
+func TestIsDone(t *testing.T) {
+	testCases := []struct {
+		in    string
+		done bool
+	}{
+		{in: "0008abcd", done: false},
+		{in: "invalid packet", done: false},
+		{in: "0009done\n", done: true},
+		{in: "0001", done: false},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.in, func(t *testing.T) {
+			require.Equal(t, tc.done, IsDone([]byte(tc.in)))
+		})
+	}
+}