feat(third_party): Check in git-appraise r/10

1 files changed, 613 insertions, 0 deletions

diff --git a/third_party/go/git-appraise/repository/mock_repo.go b/third_party/go/git-appraise/repository/mock_repo.go
new file mode 100644
index 000000000000..2d8debe48387
--- /dev/null
+++ b/third_party/go/git-appraise/repository/mock_repo.go
@@ -0,0 +1,613 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package repository
+
+import (
+	"crypto/sha1"
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+// Constants used for testing.
+// We initialize our mock repo with two branches (one of which holds a pending review),
+// and commit history that looks like this:
+//
+//  Master Branch:    A--B--D--E--F--J
+//                     \   /    \  \
+//                       C       \  \
+//                                \  \
+//  Review Branch:                 G--H--I
+//
+// Where commits "B" and "D" represent reviews that have been submitted, and "G"
+// is a pending review.
+const (
+	TestTargetRef          = "refs/heads/master"
+	TestReviewRef          = "refs/heads/ojarjur/mychange"
+	TestAlternateReviewRef = "refs/review/mychange"
+	TestRequestsRef        = "refs/notes/devtools/reviews"
+	TestCommentsRef        = "refs/notes/devtools/discuss"
+
+	TestCommitA = "A"
+	TestCommitB = "B"
+	TestCommitC = "C"
+	TestCommitD = "D"
+	TestCommitE = "E"
+	TestCommitF = "F"
+	TestCommitG = "G"
+	TestCommitH = "H"
+	TestCommitI = "I"
+	TestCommitJ = "J"
+
+	TestRequestB = `{"timestamp": "0000000001", "reviewRef": "refs/heads/ojarjur/mychange", "targetRef": "refs/heads/master", "requester": "ojarjur", "reviewers": ["ojarjur"], "description": "B"}`
+	TestRequestD = `{"timestamp": "0000000002", "reviewRef": "refs/heads/ojarjur/mychange", "targetRef": "refs/heads/master", "requester": "ojarjur", "reviewers": ["ojarjur"], "description": "D"}`
+	TestRequestG = `{"timestamp": "0000000004", "reviewRef": "refs/heads/ojarjur/mychange", "targetRef": "refs/heads/master", "requester": "ojarjur", "reviewers": ["ojarjur"], "description": "G"}
+
+{"timestamp": "0000000005", "reviewRef": "refs/heads/ojarjur/mychange", "targetRef": "refs/heads/master", "requester": "ojarjur", "reviewers": ["ojarjur"], "description": "Updated description of G"}
+
+{"timestamp": "0000000005", "reviewRef": "refs/heads/ojarjur/mychange", "targetRef": "refs/heads/master", "requester": "ojarjur", "reviewers": ["ojarjur"], "description": "Final description of G"}`
+
+	TestDiscussB = `{"timestamp": "0000000001", "author": "ojarjur", "location": {"commit": "B"}, "resolved": true}`
+	TestDiscussD = `{"timestamp": "0000000003", "author": "ojarjur", "location": {"commit": "E"}, "resolved": true}`
+)
+
+type mockCommit struct {
+	Message string   `json:"message,omitempty"`
+	Time    string   `json:"time,omitempty"`
+	Parents []string `json:"parents,omitempty"`
+}
+
+// mockRepoForTest defines an instance of Repo that can be used for testing.
+type mockRepoForTest struct {
+	Head    string
+	Refs    map[string]string            `json:"refs,omitempty"`
+	Commits map[string]mockCommit        `json:"commits,omitempty"`
+	Notes   map[string]map[string]string `json:"notes,omitempty"`
+}
+
+func (r *mockRepoForTest) createCommit(message string, time string, parents []string) (string, error) {
+	newCommit := mockCommit{
+		Message: message,
+		Time:    time,
+		Parents: parents,
+	}
+	newCommitJSON, err := json.Marshal(newCommit)
+	if err != nil {
+		return "", err
+	}
+	newCommitHash := fmt.Sprintf("%x", sha1.Sum([]byte(newCommitJSON)))
+	r.Commits[newCommitHash] = newCommit
+	return newCommitHash, nil
+}
+
+// NewMockRepoForTest returns a mocked-out instance of the Repo interface that has been pre-populated with test data.
+func NewMockRepoForTest() Repo {
+	commitA := mockCommit{
+		Message: "First commit",
+		Time:    "0",
+		Parents: nil,
+	}
+	commitB := mockCommit{
+		Message: "Second commit",
+		Time:    "1",
+		Parents: []string{TestCommitA},
+	}
+	commitC := mockCommit{
+		Message: "No, I'm the second commit",
+		Time:    "1",
+		Parents: []string{TestCommitA},
+	}
+	commitD := mockCommit{
+		Message: "Fourth commit",
+		Time:    "2",
+		Parents: []string{TestCommitB, TestCommitC},
+	}
+	commitE := mockCommit{
+		Message: "Fifth commit",
+		Time:    "3",
+		Parents: []string{TestCommitD},
+	}
+	commitF := mockCommit{
+		Message: "Sixth commit",
+		Time:    "4",
+		Parents: []string{TestCommitE},
+	}
+	commitG := mockCommit{
+		Message: "No, I'm the sixth commit",
+		Time:    "4",
+		Parents: []string{TestCommitE},
+	}
+	commitH := mockCommit{
+		Message: "Seventh commit",
+		Time:    "5",
+		Parents: []string{TestCommitG, TestCommitF},
+	}
+	commitI := mockCommit{
+		Message: "Eighth commit",
+		Time:    "6",
+		Parents: []string{TestCommitH},
+	}
+	commitJ := mockCommit{
+		Message: "No, I'm the eighth commit",
+		Time:    "6",
+		Parents: []string{TestCommitF},
+	}
+	return &mockRepoForTest{
+		Head: TestTargetRef,
+		Refs: map[string]string{
+			TestTargetRef:          TestCommitJ,
+			TestReviewRef:          TestCommitI,
+			TestAlternateReviewRef: TestCommitI,
+		},
+		Commits: map[string]mockCommit{
+			TestCommitA: commitA,
+			TestCommitB: commitB,
+			TestCommitC: commitC,
+			TestCommitD: commitD,
+			TestCommitE: commitE,
+			TestCommitF: commitF,
+			TestCommitG: commitG,
+			TestCommitH: commitH,
+			TestCommitI: commitI,
+			TestCommitJ: commitJ,
+		},
+		Notes: map[string]map[string]string{
+			TestRequestsRef: map[string]string{
+				TestCommitB: TestRequestB,
+				TestCommitD: TestRequestD,
+				TestCommitG: TestRequestG,
+			},
+			TestCommentsRef: map[string]string{
+				TestCommitB: TestDiscussB,
+				TestCommitD: TestDiscussD,
+			},
+		},
+	}
+}
+
+// GetPath returns the path to the repo.
+func (r *mockRepoForTest) GetPath() string { return "~/mockRepo/" }
+
+// GetRepoStateHash returns a hash which embodies the entire current state of a repository.
+func (r *mockRepoForTest) GetRepoStateHash() (string, error) {
+	repoJSON, err := json.Marshal(r)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("%x", sha1.Sum([]byte(repoJSON))), nil
+}
+
+// GetUserEmail returns the email address that the user has used to configure git.
+func (r *mockRepoForTest) GetUserEmail() (string, error) { return "user@example.com", nil }
+
+// GetUserSigningKey returns the key id the user has configured for
+// sigining git artifacts.
+func (r *mockRepoForTest) GetUserSigningKey() (string, error) {
+	return "gpgsig", nil
+}
+
+// GetCoreEditor returns the name of the editor that the user has used to configure git.
+func (r *mockRepoForTest) GetCoreEditor() (string, error) { return "vi", nil }
+
+// GetSubmitStrategy returns the way in which a review is submitted
+func (r *mockRepoForTest) GetSubmitStrategy() (string, error) { return "merge", nil }
+
+// HasUncommittedChanges returns true if there are local, uncommitted changes.
+func (r *mockRepoForTest) HasUncommittedChanges() (bool, error) { return false, nil }
+
+func (r *mockRepoForTest) resolveLocalRef(ref string) (string, error) {
+	if ref == "HEAD" {
+		ref = r.Head
+	}
+	if commit, ok := r.Refs[ref]; ok {
+		return commit, nil
+	}
+	if _, ok := r.Commits[ref]; ok {
+		return ref, nil
+	}
+	return "", fmt.Errorf("The ref %q does not exist", ref)
+}
+
+// VerifyCommit verifies that the supplied hash points to a known commit.
+func (r *mockRepoForTest) VerifyCommit(hash string) error {
+	if _, ok := r.Commits[hash]; !ok {
+		return fmt.Errorf("The given hash %q is not a known commit", hash)
+	}
+	return nil
+}
+
+// VerifyGitRef verifies that the supplied ref points to a known commit.
+func (r *mockRepoForTest) VerifyGitRef(ref string) error {
+	_, err := r.resolveLocalRef(ref)
+	return err
+}
+
+// GetHeadRef returns the ref that is the current HEAD.
+func (r *mockRepoForTest) GetHeadRef() (string, error) { return r.Head, nil }
+
+// GetCommitHash returns the hash of the commit pointed to by the given ref.
+func (r *mockRepoForTest) GetCommitHash(ref string) (string, error) {
+	err := r.VerifyGitRef(ref)
+	if err != nil {
+		return "", err
+	}
+	return r.resolveLocalRef(ref)
+}
+
+// ResolveRefCommit returns the commit pointed to by the given ref, which may be a remote ref.
+//
+// This differs from GetCommitHash which only works on exact matches, in that it will try to
+// intelligently handle the scenario of a ref not existing locally, but being known to exist
+// in a remote repo.
+//
+// This method should be used when a command may be performed by either the reviewer or the
+// reviewee, while GetCommitHash should be used when the encompassing command should only be
+// performed by the reviewee.
+func (r *mockRepoForTest) ResolveRefCommit(ref string) (string, error) {
+	if commit, err := r.resolveLocalRef(ref); err == nil {
+		return commit, err
+	}
+	return r.resolveLocalRef(strings.Replace(ref, "refs/heads/", "refs/remotes/origin/", 1))
+}
+
+func (r *mockRepoForTest) getCommit(ref string) (mockCommit, error) {
+	commit, err := r.resolveLocalRef(ref)
+	return r.Commits[commit], err
+}
+
+// GetCommitMessage returns the message stored in the commit pointed to by the given ref.
+func (r *mockRepoForTest) GetCommitMessage(ref string) (string, error) {
+	commit, err := r.getCommit(ref)
+	if err != nil {
+		return "", err
+	}
+	return commit.Message, nil
+}
+
+// GetCommitTime returns the commit time of the commit pointed to by the given ref.
+func (r *mockRepoForTest) GetCommitTime(ref string) (string, error) {
+	commit, err := r.getCommit(ref)
+	if err != nil {
+		return "", err
+	}
+	return commit.Time, nil
+}
+
+// GetLastParent returns the last parent of the given commit (as ordered by git).
+func (r *mockRepoForTest) GetLastParent(ref string) (string, error) {
+	commit, err := r.getCommit(ref)
+	if len(commit.Parents) > 0 {
+		return commit.Parents[len(commit.Parents)-1], err
+	}
+	return "", err
+}
+
+// GetCommitDetails returns the details of a commit's metadata.
+func (r *mockRepoForTest) GetCommitDetails(ref string) (*CommitDetails, error) {
+	commit, err := r.getCommit(ref)
+	if err != nil {
+		return nil, err
+	}
+	var details CommitDetails
+	details.Author = "Test Author"
+	details.AuthorEmail = "author@example.com"
+	details.Summary = commit.Message
+	details.Time = commit.Time
+	details.Parents = commit.Parents
+	return &details, nil
+}
+
+// ancestors returns the breadth-first traversal of a commit's ancestors
+func (r *mockRepoForTest) ancestors(commit string) ([]string, error) {
+	queue := []string{commit}
+	var ancestors []string
+	for queue != nil {
+		var nextQueue []string
+		for _, c := range queue {
+			commit, err := r.getCommit(c)
+			if err != nil {
+				return nil, err
+			}
+			parents := commit.Parents
+			nextQueue = append(nextQueue, parents...)
+			ancestors = append(ancestors, parents...)
+		}
+		queue = nextQueue
+	}
+	return ancestors, nil
+}
+
+// IsAncestor determines if the first argument points to a commit that is an ancestor of the second.
+func (r *mockRepoForTest) IsAncestor(ancestor, descendant string) (bool, error) {
+	var err error
+	ancestor, err = r.resolveLocalRef(ancestor)
+	if err != nil {
+		return false, err
+	}
+	descendant, err = r.resolveLocalRef(descendant)
+	if err != nil {
+		return false, err
+	}
+	if ancestor == descendant {
+		return true, nil
+	}
+	descendantCommit, err := r.getCommit(descendant)
+	if err != nil {
+		return false, err
+	}
+	for _, parent := range descendantCommit.Parents {
+		if t, e := r.IsAncestor(ancestor, parent); e == nil && t {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+// MergeBase determines if the first commit that is an ancestor of the two arguments.
+func (r *mockRepoForTest) MergeBase(a, b string) (string, error) {
+	ancestors, err := r.ancestors(a)
+	if err != nil {
+		return "", err
+	}
+	for _, ancestor := range ancestors {
+		if t, e := r.IsAncestor(ancestor, b); e == nil && t {
+			return ancestor, nil
+		}
+	}
+	return "", nil
+}
+
+// Diff computes the diff between two given commits.
+func (r *mockRepoForTest) Diff(left, right string, diffArgs ...string) (string, error) {
+	return fmt.Sprintf("Diff between %q and %q", left, right), nil
+}
+
+// Show returns the contents of the given file at the given commit.
+func (r *mockRepoForTest) Show(commit, path string) (string, error) {
+	return fmt.Sprintf("%s:%s", commit, path), nil
+}
+
+// SwitchToRef changes the currently-checked-out ref.
+func (r *mockRepoForTest) SwitchToRef(ref string) error {
+	r.Head = ref
+	return nil
+}
+
+// ArchiveRef adds the current commit pointed to by the 'ref' argument
+// under the ref specified in the 'archive' argument.
+//
+// Both the 'ref' and 'archive' arguments are expected to be the fully
+// qualified names of git refs (e.g. 'refs/heads/my-change' or
+// 'refs/archive/devtools').
+//
+// If the ref pointed to by the 'archive' argument does not exist
+// yet, then it will be created.
+func (r *mockRepoForTest) ArchiveRef(ref, archive string) error {
+	commitToArchive, err := r.resolveLocalRef(ref)
+	if err != nil {
+		return err
+	}
+	var archiveParents []string
+	if archiveCommit, err := r.resolveLocalRef(archive); err == nil {
+		archiveParents = []string{archiveCommit, commitToArchive}
+	} else {
+		archiveParents = []string{commitToArchive}
+	}
+	archiveCommit, err := r.createCommit("Archiving", "Nowish", archiveParents)
+	if err != nil {
+		return err
+	}
+	r.Refs[archive] = archiveCommit
+	return nil
+}
+
+// MergeRef merges the given ref into the current one.
+//
+// The ref argument is the ref to merge, and fastForward indicates that the
+// current ref should only move forward, as opposed to creating a bubble merge.
+func (r *mockRepoForTest) MergeRef(ref string, fastForward bool, messages ...string) error {
+	newCommitHash, err := r.resolveLocalRef(ref)
+	if err != nil {
+		return err
+	}
+	if !fastForward {
+		origCommit, err := r.resolveLocalRef(r.Head)
+		if err != nil {
+			return err
+		}
+		newCommit, err := r.getCommit(ref)
+		if err != nil {
+			return err
+		}
+		message := strings.Join(messages, "\n\n")
+		time := newCommit.Time
+		parents := []string{origCommit, newCommitHash}
+		newCommitHash, err = r.createCommit(message, time, parents)
+		if err != nil {
+			return err
+		}
+	}
+	r.Refs[r.Head] = newCommitHash
+	return nil
+}
+
+// MergeAndSignRef merges the given ref into the current one and signs the
+// merge.
+//
+// The ref argument is the ref to merge, and fastForward indicates that the
+// current ref should only move forward, as opposed to creating a bubble merge.
+func (r *mockRepoForTest) MergeAndSignRef(ref string, fastForward bool,
+	messages ...string) error {
+	return nil
+}
+
+// RebaseRef rebases the current ref onto the given one.
+func (r *mockRepoForTest) RebaseRef(ref string) error {
+	parentHash := r.Refs[ref]
+	origCommit, err := r.getCommit(r.Head)
+	if err != nil {
+		return err
+	}
+	newCommitHash, err := r.createCommit(origCommit.Message, origCommit.Time, []string{parentHash})
+	if err != nil {
+		return err
+	}
+	if strings.HasPrefix(r.Head, "refs/heads/") {
+		r.Refs[r.Head] = newCommitHash
+	} else {
+		// The current head is not a branch, so updating
+		// it should leave us in a detached-head state.
+		r.Head = newCommitHash
+	}
+	return nil
+}
+
+// RebaseAndSignRef rebases the current ref onto the given one and signs the
+// result.
+func (r *mockRepoForTest) RebaseAndSignRef(ref string) error { return nil }
+
+// ListCommits returns the list of commits reachable from the given ref.
+//
+// The generated list is in chronological order (with the oldest commit first).
+//
+// If the specified ref does not exist, then this method returns an empty result.
+func (r *mockRepoForTest) ListCommits(ref string) []string { return nil }
+
+// ListCommitsBetween returns the list of commits between the two given revisions.
+//
+// The "from" parameter is the starting point (exclusive), and the "to"
+// parameter is the ending point (inclusive).
+//
+// The "from" commit does not need to be an ancestor of the "to" commit. If it
+// is not, then the merge base of the two is used as the starting point.
+// Admittedly, this makes calling these the "between" commits is a bit of a
+// misnomer, but it also makes the method easier to use when you want to
+// generate the list of changes in a feature branch, as it eliminates the need
+// to explicitly calculate the merge base. This also makes the semantics of the
+// method compatible with git's built-in "rev-list" command.
+//
+// The generated list is in chronological order (with the oldest commit first).
+func (r *mockRepoForTest) ListCommitsBetween(from, to string) ([]string, error) {
+	commits := []string{to}
+	potentialCommits, _ := r.ancestors(to)
+	for _, commit := range potentialCommits {
+		blocked, err := r.IsAncestor(commit, from)
+		if err != nil {
+			return nil, err
+		}
+		if !blocked {
+			commits = append(commits, commit)
+		}
+	}
+	return commits, nil
+}
+
+// GetNotes reads the notes from the given ref that annotate the given revision.
+func (r *mockRepoForTest) GetNotes(notesRef, revision string) []Note {
+	notesText := r.Notes[notesRef][revision]
+	var notes []Note
+	for _, line := range strings.Split(notesText, "\n") {
+		notes = append(notes, Note(line))
+	}
+	return notes
+}
+
+// GetAllNotes reads the contents of the notes under the given ref for every commit.
+//
+// The returned value is a mapping from commit hash to the list of notes for that commit.
+//
+// This is the batch version of the corresponding GetNotes(...) method.
+func (r *mockRepoForTest) GetAllNotes(notesRef string) (map[string][]Note, error) {
+	notesMap := make(map[string][]Note)
+	for _, commit := range r.ListNotedRevisions(notesRef) {
+		notesMap[commit] = r.GetNotes(notesRef, commit)
+	}
+	return notesMap, nil
+}
+
+// AppendNote appends a note to a revision under the given ref.
+func (r *mockRepoForTest) AppendNote(ref, revision string, note Note) error {
+	existingNotes := r.Notes[ref][revision]
+	newNotes := existingNotes + "\n" + string(note)
+	r.Notes[ref][revision] = newNotes
+	return nil
+}
+
+// ListNotedRevisions returns the collection of revisions that are annotated by notes in the given ref.
+func (r *mockRepoForTest) ListNotedRevisions(notesRef string) []string {
+	var revisions []string
+	for revision := range r.Notes[notesRef] {
+		if _, ok := r.Commits[revision]; ok {
+			revisions = append(revisions, revision)
+		}
+	}
+	return revisions
+}
+
+// PushNotes pushes git notes to a remote repo.
+func (r *mockRepoForTest) PushNotes(remote, notesRefPattern string) error { return nil }
+
+// PullNotes fetches the contents of the given notes ref from a remote repo,
+// and then merges them with the corresponding local notes using the
+// "cat_sort_uniq" strategy.
+func (r *mockRepoForTest) PullNotes(remote, notesRefPattern string) error { return nil }
+
+// PushNotesAndArchive pushes the given notes and archive refs to a remote repo.
+func (r *mockRepoForTest) PushNotesAndArchive(remote, notesRefPattern, archiveRefPattern string) error {
+	return nil
+}
+
+// PullNotesAndArchive fetches the contents of the notes and archives refs from
+// a remote repo, and merges them with the corresponding local refs.
+//
+// For notes refs, we assume that every note can be automatically merged using
+// the 'cat_sort_uniq' strategy (the git-appraise schemas fit that requirement),
+// so we automatically merge the remote notes into the local notes.
+//
+// For "archive" refs, they are expected to be used solely for maintaining
+// reachability of commits that are part of the history of any reviews,
+// so we do not maintain any consistency with their tree objects. Instead,
+// we merely ensure that their history graph includes every commit that we
+// intend to keep.
+func (r *mockRepoForTest) PullNotesAndArchive(remote, notesRefPattern, archiveRefPattern string) error {
+	return nil
+}
+
+// MergeNotes merges in the remote's state of the archives reference into
+// the local repository's.
+func (repo *mockRepoForTest) MergeNotes(remote, notesRefPattern string) error {
+	return nil
+}
+
+// MergeArchives merges in the remote's state of the archives reference into
+// the local repository's.
+func (repo *mockRepoForTest) MergeArchives(remote,
+	archiveRefPattern string) error {
+	return nil
+}
+
+// FetchAndReturnNewReviewHashes fetches the notes "branches" and then susses
+// out the IDs (the revision the review points to) of any new reviews, then
+// returns that list of IDs.
+//
+// This is accomplished by determining which files in the notes tree have
+// changed because the _names_ of these files correspond to the revisions they
+// point to.
+func (repo *mockRepoForTest) FetchAndReturnNewReviewHashes(remote, notesRefPattern,
+	archiveRefPattern string) ([]string, error) {
+	return nil, nil
+}