1 files changed, 300 insertions, 0 deletions
diff --git a/spec/test/parser_test.go b/spec/test/parser_test.go
new file mode 100644
index 0000000..6e77f6d
--- /dev/null
+++ b/spec/test/parser_test.go
@@ -0,0 +1,300 @@
+package test
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func TestDiffTree(t *testing.T) {
+	tests := []struct {
+		t1        *Tree
+		t2        *Tree
+		different bool
+	}{
+		{
+			t1: NewTree("a"),
+			t2: NewTree("a"),
+		},
+		{
+			t1: NewTree("a",
+				NewTree("b"),
+			),
+			t2: NewTree("a",
+				NewTree("b"),
+			),
+		},
+		{
+			t1: NewTree("a",
+				NewTree("b"),
+				NewTree("c"),
+				NewTree("d"),
+			),
+			t2: NewTree("a",
+				NewTree("b"),
+				NewTree("c"),
+				NewTree("d"),
+			),
+		},
+		{
+			t1: NewTree("a",
+				NewTree("b",
+					NewTree("c"),
+				),
+				NewTree("d",
+					NewTree("d"),
+				),
+			),
+			t2: NewTree("a",
+				NewTree("b",
+					NewTree("c"),
+				),
+				NewTree("d",
+					NewTree("d"),
+				),
+			),
+		},
+		{
+			t1:        NewTree("a"),
+			t2:        NewTree("b"),
+			different: true,
+		},
+		{
+			t1: NewTree("a",
+				NewTree("b"),
+			),
+			t2:        NewTree("a"),
+			different: true,
+		},
+		{
+			t1: NewTree("a"),
+			t2: NewTree("a",
+				NewTree("b"),
+			),
+			different: true,
+		},
+		{
+			t1: NewTree("a",
+				NewTree("b"),
+			),
+			t2: NewTree("a",
+				NewTree("c"),
+			),
+			different: true,
+		},
+		{
+			t1: NewTree("a",
+				NewTree("b"),
+				NewTree("c"),
+				NewTree("d"),
+			),
+			t2: NewTree("a",
+				NewTree("b"),
+				NewTree("c"),
+			),
+			different: true,
+		},
+		{
+			t1: NewTree("a",
+				NewTree("b"),
+				NewTree("c"),
+			),
+			t2: NewTree("a",
+				NewTree("b"),
+				NewTree("c"),
+				NewTree("d"),
+			),
+			different: true,
+		},
+		{
+			t1: NewTree("a",
+				NewTree("b",
+					NewTree("c"),
+				),
+			),
+			t2: NewTree("a",
+				NewTree("b",
+					NewTree("d"),
+				),
+			),
+			different: true,
+		},
+	}
+	for i, tt := range tests {
+		t.Run(fmt.Sprintf("#%v", i), func(t *testing.T) {
+			diffs := DiffTree(tt.t1, tt.t2)
+			if tt.different && len(diffs) == 0 {
+				t.Fatalf("unexpected result")
+			} else if !tt.different && len(diffs) > 0 {
+				t.Fatalf("unexpected result")
+			}
+		})
+	}
+}
+
+func TestParseTestCase(t *testing.T) {
+	tests := []struct {
+		src      string
+		tc       *TestCase
+		parseErr bool
+	}{
+		{
+			src: `test
+---
+foo
+---
+(foo)
+`,
+			tc: &TestCase{
+				Description: "test",
+				Source:      []byte("foo"),
+				Output:      NewTree("foo").Fill(),
+			},
+		},
+		{
+			src: `
+test
+
+---
+
+foo
+
+---
+
+(foo)
+
+`,
+			tc: &TestCase{
+				Description: "\ntest\n",
+				Source:      []byte("\nfoo\n"),
+				Output:      NewTree("foo").Fill(),
+			},
+		},
+		// The length of a part delimiter may be greater than 3.
+		{
+			src: `
+test
+----
+foo
+----
+(foo)
+`,
+			tc: &TestCase{
+				Description: "\ntest",
+				Source:      []byte("foo"),
+				Output:      NewTree("foo").Fill(),
+			},
+		},
+		// The description part may be empty.
+		{
+			src: `----
+foo
+----
+(foo)
+`,
+			tc: &TestCase{
+				Description: "",
+				Source:      []byte("foo"),
+				Output:      NewTree("foo").Fill(),
+			},
+		},
+		// The source part may be empty.
+		{
+			src: `test
+---
+---
+(foo)
+`,
+			tc: &TestCase{
+				Description: "test",
+				Source:      []byte{},
+				Output:      NewTree("foo").Fill(),
+			},
+		},
+		// NOTE: If there is a delimiter at the end of a test case, we really want to make it a syntax error,
+		// but we allow it to simplify the implementation of the parser.
+		{
+			src: `test
+----
+foo
+----
+(foo)
+---
+`,
+			tc: &TestCase{
+				Description: "test",
+				Source:      []byte("foo"),
+				Output:      NewTree("foo").Fill(),
+			},
+		},
+		{
+			src:      ``,
+			parseErr: true,
+		},
+		{
+			src: `test
+---
+`,
+			parseErr: true,
+		},
+		{
+			src: `test
+---
+foo
+`,
+			parseErr: true,
+		},
+		{
+			src: `test
+---
+foo
+---
+`,
+			parseErr: true,
+		},
+		{
+			src: `test
+--
+foo
+--
+(foo)
+`,
+			parseErr: true,
+		},
+		{
+			src: `test
+---
+foo
+---
+?
+`,
+			parseErr: true,
+		},
+	}
+	for i, tt := range tests {
+		t.Run(fmt.Sprintf("#%v", i), func(t *testing.T) {
+			tc, err := ParseTestCase(strings.NewReader(tt.src))
+			if tt.parseErr {
+				if err == nil {
+					t.Fatalf("an expected error didn't occur")
+				}
+			} else {
+				if err != nil {
+					t.Fatal(err)
+				}
+				testTestCase(t, tt.tc, tc)
+			}
+		})
+	}
+}
+
+func testTestCase(t *testing.T, expected, actual *TestCase) {
+	t.Helper()
+
+	if expected.Description != actual.Description ||
+		!reflect.DeepEqual(expected.Source, actual.Source) ||
+		len(DiffTree(expected.Output, actual.Output)) > 0 {
+		t.Fatalf("unexpected test case: want: %#v, got: %#v", expected, actual)
+	}
+}