preview_repository_comparison_test.go

package graphqlbackend

import (
	"context"
	"testing"

	"github.com/google/go-cmp/cmp"
	"github.com/sourcegraph/go-diff/diff"
	"github.com/sourcegraph/sourcegraph/cmd/frontend/backend"
	"github.com/sourcegraph/sourcegraph/cmd/frontend/types"
	"github.com/sourcegraph/sourcegraph/internal/api"
	"github.com/sourcegraph/sourcegraph/internal/vcs/git"
)

func TestPreviewRepositoryComparisonResolver(t *testing.T) {
	ctx := context.Background()

	const testDiffFiles = 3
	const testOldFile = `First
Second
Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 7
Line 8
Line 9
Line 10
`

	const testDiff = `diff --git INSTALL.md INSTALL.md
index e5af166..d44c3fc 100644
--- INSTALL.md
+++ INSTALL.md
@@ -3,10 +3,10 @@
 Line 1
 Line 2
 Line 3
-Line 4
+This is cool: Line 4
 Line 5
 Line 6
-Line 7
-Line 8
+Another Line 7
+Foobar Line 8
 Line 9
 Line 10
diff --git JOKES.md JOKES.md
index ea80abf..1b86505 100644
--- JOKES.md
+++ JOKES.md
@@ -4,10 +4,10 @@ Joke #1
 Joke #2
 Joke #3
 Joke #4
-Joke #5
+This is not funny: Joke #5
 Joke #6
-Joke #7
+This one is good: Joke #7
 Joke #8
-Joke #9
+Waffle: Joke #9
 Joke #10
 Joke #11
diff --git README.md README.md
index 9bd8209..d2acfa9 100644
--- README.md
+++ README.md
@@ -1,12 +1,13 @@
 # README

-Line 1
+Foobar Line 1
 Line 2
 Line 3
 Line 4
 Line 5
-Line 6
+Barfoo Line 6
 Line 7
 Line 8
 Line 9
 Line 10
+Another line
`
	wantBaseRef := "refs/heads/master"
	wantHeadRevision := api.CommitID("b69072d5f687b31b9f6ae3ceafdc24c259c4b9ec")
	mockBackendCommits(t, api.CommitID(wantBaseRef), wantHeadRevision)

	repo := &types.Repo{ID: api.RepoID(1), Name: "github.com/sourcegraph/sourcegraph"}

	previewComparisonResolver, err := NewPreviewRepositoryComparisonResolver(ctx, NewRepositoryResolver(repo), string(wantHeadRevision), testDiff)
	if err != nil {
		t.Fatal(err)
	}

	t.Run("Pagination", func(t *testing.T) {
		endCursors := []string{"1", "2"}
		totalCount := int32(testDiffFiles)

		tests := []struct {
			first int32
			after string

			wantNodeCount int

			wantTotalCount *int32

			wantHasNextPage bool
			wantEndCursor   *string
		}{
			{
				first:           1,
				after:           "",
				wantNodeCount:   1,
				wantHasNextPage: true,
				wantEndCursor:   &endCursors[0],
				wantTotalCount:  nil,
			},
			{
				first:           1,
				after:           endCursors[0],
				wantNodeCount:   1,
				wantHasNextPage: true,
				wantEndCursor:   &endCursors[1],
				wantTotalCount:  nil,
			},
			{
				first:           1,
				after:           endCursors[1],
				wantNodeCount:   1,
				wantHasNextPage: false,
				wantEndCursor:   nil,
				wantTotalCount:  &totalCount,
			},
			{
				first:           testDiffFiles + 1,
				after:           "",
				wantNodeCount:   testDiffFiles,
				wantHasNextPage: false,
				wantEndCursor:   nil,
				wantTotalCount:  &totalCount,
			},
		}

		for _, tc := range tests {
			args := &FileDiffsConnectionArgs{First: &tc.first}
			if tc.after != "" {
				args.After = &tc.after
			}

			conn, err := previewComparisonResolver.FileDiffs(ctx, args)
			if err != nil {
				t.Fatal(err)
			}

			nodes, err := conn.Nodes(ctx)
			if err != nil {
				t.Fatal(err)
			}

			if len(nodes) != tc.wantNodeCount {
				t.Fatalf("wrong length of nodes. want=%d, have=%d", tc.wantNodeCount, len(nodes))
			}

			pageInfo, err := conn.PageInfo(ctx)
			if err != nil {
				t.Fatal(err)
			}

			if pageInfo.HasNextPage() != tc.wantHasNextPage {
				t.Fatalf("pageInfo HasNextPage wrong. want=%t, have=%t", tc.wantHasNextPage, pageInfo.HasNextPage())
			}

			if diff := cmp.Diff(tc.wantEndCursor, pageInfo.EndCursor()); diff != "" {
				t.Fatalf("(-want +got):\n%s", diff)
			}

			totalCount, err := conn.TotalCount(ctx)
			if err != nil {
				t.Fatal(err)
			}
			if diff := cmp.Diff(tc.wantTotalCount, totalCount); diff != "" {
				t.Fatalf("wrong totalCount: %s", diff)
			}
		}
	})

	t.Run("NewFile resolver", func(t *testing.T) {
		fileDiffConnection, err := previewComparisonResolver.FileDiffs(ctx, &FileDiffsConnectionArgs{})
		if err != nil {
			t.Fatal(err)
		}
		fileDiffs, err := fileDiffConnection.Nodes(ctx)
		if err != nil {
			t.Fatal(err)
		}

		if have, want := len(fileDiffs), testDiffFiles; have != want {
			t.Fatalf("invalid len(FileDiffs.Nodes). want=%d have=%d", want, len(fileDiffs))
		}
		fileDiff := fileDiffs[0]

		git.Mocks.ReadFile = func(commit api.CommitID, name string) ([]byte, error) {
			if name != "INSTALL.md" {
				t.Fatalf("ReadFile received call for wrong file: %s", name)
			}

			return []byte(testOldFile), nil
		}
		defer func() { git.Mocks.ReadFile = nil }()

		newFile := fileDiff.NewFile()
		if newFile == nil {
			t.Fatal("NewFile is null")
		}

		wantNewFileContent := `First
Second
Line 1
Line 2
Line 3
This is cool: Line 4
Line 5
Line 6
Another Line 7
Foobar Line 8
Line 9
Line 10
`

		haveContent, err := newFile.Content(ctx)
		if err != nil {
			t.Fatal(err)
		}
		if haveContent != wantNewFileContent {
			t.Fatalf("wrong file content. want=%q have=%q", wantNewFileContent, haveContent)
		}
	})
}

func TestApplyPatch(t *testing.T) {
	tests := []struct {
		name     string
		file     string
		patch    string
		wantFile string
	}{
		{
			name: "replace in middle",
			file: `1 some
2
3
4
5
6
7 super awesome
8
9
10
11
12
13
14 file
15
16
17
18 oh yes
`,
			patch: `diff --git a/test b/test
index 38dea4a..d81676e 100644
--- a/test
+++ b/test
@@ -4,7 +4,7 @@
 4
 5
 6
-7 super awesome
+7 super mega awesome
 8
 9
 10
`,
			wantFile: `1 some
2
3
4
5
6
7 super mega awesome
8
9
10
11
12
13
14 file
15
16
17
18 oh yes
`,
		},
		{
			name: "delete file",
			file: `1 some
2
3
`,
			patch: `diff --git a/test b/test
deleted file mode 100644
index 2e0cf96..0000000
--- a/test
+++ /dev/null
@@ -1,3 +0,0 @@
-1 some
-2
-3
`,
			wantFile: "",
		},
		{
			name: "New file, additional newline at end",
			file: "",
			patch: `diff --git a/file2.txt b/file2.txt
new file mode 100644
index 0000000..122f5d9
--- /dev/null
+++ b/file2.txt
@@ -0,0 +1 @@
+filecontent
+
`,
			wantFile: `filecontent

`,
		},
		{
			name: "New file",
			file: "",
			patch: `diff --git a/file2.txt b/file2.txt
new file mode 100644
index 0000000..122f5d9
--- /dev/null
+++ b/file2.txt
@@ -0,0 +1 @@
+filecontent
`,
			wantFile: `filecontent
`,
		},
	}

	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			fileDiff, err := diff.ParseFileDiff([]byte(tc.patch))
			if err != nil {
				t.Fatal(err)
			}
			have := applyPatch(tc.file, fileDiff)
			if have != tc.wantFile {
				t.Fatalf("wrong patched file content %q, want=%q", have, tc.wantFile)
			}
		})
	}
}

func mockBackendCommits(t *testing.T, revs ...api.CommitID) {
	t.Helper()

	byRev := map[api.CommitID]struct{}{}
	for _, r := range revs {
		byRev[r] = struct{}{}
	}

	backend.Mocks.Repos.ResolveRev = func(_ context.Context, _ *types.Repo, rev string) (api.CommitID, error) {
		if _, ok := byRev[api.CommitID(rev)]; !ok {
			t.Fatalf("ResolveRev received unexpected rev: %q", rev)
		}
		return api.CommitID(rev), nil
	}
	t.Cleanup(func() { backend.Mocks.Repos.ResolveRev = nil })

	backend.Mocks.Repos.GetCommit = func(_ context.Context, _ *types.Repo, id api.CommitID) (*git.Commit, error) {
		if _, ok := byRev[id]; !ok {
			t.Fatalf("GetCommit received unexpected ID: %s", id)
		}
		return &git.Commit{ID: id}, nil
	}
	t.Cleanup(func() { backend.Mocks.Repos.GetCommit = nil })
}