modfile: add tests for AddReplace and DropReplace (#72)

modfile: add tests for AddReplace and DropReplace

Author: dmitris

modfile/replace_test.go

@@ -0,0 +1,103 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package modfile
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+)
+
+var addDropReplaceTests = []struct {
+	in      string
+	oldpath string
+	oldvers string
+	newpath string
+	newvers string
+	dropOld bool
+	out     string
+}{
+	{
+		`
+		module m
+		require x.y/z v1.2.3
+		`,
+		"x.y/z", "v1.2.3",
+		"my.x.y/z", "v1.2.3",
+		false,
+		`
+		module m
+		require x.y/z v1.2.3
+		replace x.y/z v1.2.3 => my.x.y/z v1.2.3
+		`,
+	},
+
+	{
+		`
+		module m
+		require x.y/z v1.2.3
+		replace x.y/z => my.x.y/z v0.0.0-20190214113530-db6c41c15648
+		`,
+		"x.y/z", "",
+		"my.x.y/z", "v1.2.3",
+		true,
+		`
+		module m
+		require x.y/z v1.2.3
+		replace x.y/z => my.x.y/z v1.2.3
+		`,
+	},
+	{
+		`
+		module m
+		require x.y/z v1.2.3
+		replace x.y/z => my.x.y/z v0.0.0-20190214113530-db6c41c15648
+		`,
+		"x.y/z", "",
+		"", "", // empty newpath and newvers - drop only, no add
+		true,
+		`
+		module m
+		require x.y/z v1.2.3
+		`,
+	},
+}
+
+func TestAddDropReplace(t *testing.T) {
+	for i, tt := range addDropReplaceTests {
+		t.Run(fmt.Sprintf("#%d", i), func(t *testing.T) {
+			f, err := Parse("in", []byte(tt.in), nil)
+			if err != nil {
+				t.Fatal(err)
+			}
+			g, err := Parse("out", []byte(tt.out), nil)
+			if err != nil {
+				t.Fatal(err)
+			}
+			golden, err := g.Format()
+			if err != nil {
+				t.Fatal(err)
+			}
+			if tt.dropOld {
+				if err := f.DropReplace(tt.oldpath, tt.oldvers); err != nil {
+					t.Fatal(err)
+				}
+			}
+			if tt.newpath != "" || tt.newvers != "" {
+				if err := f.AddReplace(tt.oldpath, tt.oldvers, tt.newpath, tt.newvers); err != nil {
+					t.Fatal(err)
+				}
+			}
+			f.Cleanup()
+			out, err := f.Format()
+			if err != nil {
+				t.Fatal(err)
+			}
+			if !bytes.Equal(out, golden) {
+				t.Errorf("have:\n%s\nwant:\n%s", out, golden)
+			}
+		})
+	}
+}