Merge pull request #332 from ezwiebel/rebase-wrapper

Rebase wrapper

git.go

@@ -53,6 +53,7 @@ const (
 	ErrClassFilter     ErrorClass = C.GITERR_FILTER
 	ErrClassRevert     ErrorClass = C.GITERR_REVERT
 	ErrClassCallback   ErrorClass = C.GITERR_CALLBACK
+	ErrClassRebase     ErrorClass = C.GITERR_REBASE
 )
 
 type ErrorCode int

rebase.go

@@ -0,0 +1,252 @@
+package git
+
+/*
+#include <git2.h>
+*/
+import "C"
+import (
+	"runtime"
+	"unsafe"
+)
+
+// RebaseOperationType is the type of rebase operation
+type RebaseOperationType uint
+
+const (
+	// RebaseOperationPick The given commit is to be cherry-picked.  The client should commit the changes and continue if there are no conflicts.
+	RebaseOperationPick RebaseOperationType = C.GIT_REBASE_OPERATION_PICK
+	// RebaseOperationEdit The given commit is to be cherry-picked, but the client should stop to allow the user to edit the changes before committing them.
+	RebaseOperationEdit RebaseOperationType = C.GIT_REBASE_OPERATION_EDIT
+	// RebaseOperationSquash The given commit is to be squashed into the previous commit.  The commit message will be merged with the previous message.
+	RebaseOperationSquash RebaseOperationType = C.GIT_REBASE_OPERATION_SQUASH
+	// RebaseOperationFixup No commit will be cherry-picked.  The client should run the given command and (if successful) continue.
+	RebaseOperationFixup RebaseOperationType = C.GIT_REBASE_OPERATION_FIXUP
+	// RebaseOperationExec No commit will be cherry-picked.  The client should run the given command and (if successful) continue.
+	RebaseOperationExec RebaseOperationType = C.GIT_REBASE_OPERATION_EXEC
+)
+
+// RebaseOperation describes a single instruction/operation to be performed during the rebase.
+type RebaseOperation struct {
+	Type RebaseOperationType
+	Id   *Oid
+	Exec string
+}
+
+func newRebaseOperationFromC(c *C.git_rebase_operation) *RebaseOperation {
+	operation := &RebaseOperation{}
+	operation.Type = RebaseOperationType(c._type)
+	operation.Id = newOidFromC(&c.id)
+	operation.Exec = C.GoString(c.exec)
+
+	return operation
+}
+
+// RebaseOptions are used to tell the rebase machinery how to operate
+type RebaseOptions struct {
+	Version         uint
+	Quiet           int
+	InMemory        int
+	RewriteNotesRef string
+	MergeOptions    MergeOptions
+	CheckoutOptions CheckoutOpts
+}
+
+// DefaultRebaseOptions returns a RebaseOptions with default values.
+func DefaultRebaseOptions() (RebaseOptions, error) {
+	opts := C.git_rebase_options{}
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	ecode := C.git_rebase_init_options(&opts, C.GIT_REBASE_OPTIONS_VERSION)
+	if ecode < 0 {
+		return RebaseOptions{}, MakeGitError(ecode)
+	}
+	return rebaseOptionsFromC(&opts), nil
+}
+
+func rebaseOptionsFromC(opts *C.git_rebase_options) RebaseOptions {
+	return RebaseOptions{
+		Version:         uint(opts.version),
+		Quiet:           int(opts.quiet),
+		InMemory:        int(opts.inmemory),
+		RewriteNotesRef: C.GoString(opts.rewrite_notes_ref),
+		MergeOptions:    mergeOptionsFromC(&opts.merge_options),
+		CheckoutOptions: checkoutOptionsFromC(&opts.checkout_options),
+	}
+}
+
+func (ro *RebaseOptions) toC() *C.git_rebase_options {
+	if ro == nil {
+		return nil
+	}
+	return &C.git_rebase_options{
+		version:           C.uint(ro.Version),
+		quiet:             C.int(ro.Quiet),
+		inmemory:          C.int(ro.InMemory),
+		rewrite_notes_ref: mapEmptyStringToNull(ro.RewriteNotesRef),
+		merge_options:     *ro.MergeOptions.toC(),
+		checkout_options:  *ro.CheckoutOptions.toC(),
+	}
+}
+
+func mapEmptyStringToNull(ref string) *C.char {
+	if ref == "" {
+		return nil
+	}
+	return C.CString(ref)
+}
+
+// Rebase is the struct representing a Rebase object.
+type Rebase struct {
+	ptr *C.git_rebase
+}
+
+// InitRebase initializes a rebase operation to rebase the changes in branch relative to upstream onto another branch.
+func (r *Repository) InitRebase(branch *AnnotatedCommit, upstream *AnnotatedCommit, onto *AnnotatedCommit, opts *RebaseOptions) (*Rebase, error) {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	if branch == nil {
+		branch = &AnnotatedCommit{ptr: nil}
+	}
+
+	if upstream == nil {
+		upstream = &AnnotatedCommit{ptr: nil}
+	}
+
+	if onto == nil {
+		onto = &AnnotatedCommit{ptr: nil}
+	}
+
+	var ptr *C.git_rebase
+	err := C.git_rebase_init(&ptr, r.ptr, branch.ptr, upstream.ptr, onto.ptr, opts.toC())
+	if err < 0 {
+		return nil, MakeGitError(err)
+	}
+
+	return newRebaseFromC(ptr), nil
+}
+
+// OpenRebase opens an existing rebase that was previously started by either an invocation of InitRebase or by another client.
+func (r *Repository) OpenRebase(opts *RebaseOptions) (*Rebase, error) {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	var ptr *C.git_rebase
+	err := C.git_rebase_open(&ptr, r.ptr, opts.toC())
+	if err < 0 {
+		return nil, MakeGitError(err)
+	}
+
+	return newRebaseFromC(ptr), nil
+}
+
+// OperationAt gets the rebase operation specified by the given index.
+func (rebase *Rebase) OperationAt(index uint) *RebaseOperation {
+	operation := C.git_rebase_operation_byindex(rebase.ptr, C.size_t(index))
+	
+	return newRebaseOperationFromC(operation)
+}
+
+// CurrentOperationIndex gets the index of the rebase operation that is currently being applied.
+// Returns an error if no rebase operation is currently applied.
+func (rebase *Rebase) CurrentOperationIndex() (uint, error) {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	operationIndex := int(C.git_rebase_operation_current(rebase.ptr))
+	if operationIndex == C.GIT_REBASE_NO_OPERATION {
+		return 0, MakeGitError(C.GIT_REBASE_NO_OPERATION)
+	}
+
+	return uint(operationIndex), nil
+}
+
+// OperationCount gets the count of rebase operations that are to be applied.
+func (rebase *Rebase) OperationCount() uint {
+	return uint(C.git_rebase_operation_entrycount(rebase.ptr))
+}
+
+// Next performs the next rebase operation and returns the information about it.
+// If the operation is one that applies a patch (which is any operation except RebaseOperationExec)
+// then the patch will be applied and the index and working directory will be updated with the changes.
+// If there are conflicts, you will need to address those before committing the changes.
+func (rebase *Rebase) Next() (*RebaseOperation, error) {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	var ptr *C.git_rebase_operation
+	err := C.git_rebase_next(&ptr, rebase.ptr)
+	if err < 0 {
+		return nil, MakeGitError(err)
+	}
+
+	return newRebaseOperationFromC(ptr), nil
+}
+
+// Commit commits the current patch.
+// You must have resolved any conflicts that were introduced during the patch application from the Next() invocation.
+func (rebase *Rebase) Commit(ID *Oid, author, committer *Signature, message string) error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	authorSig, err := author.toC()
+	if err != nil {
+		return err
+	}
+	defer C.git_signature_free(authorSig)
+
+	committerSig, err := committer.toC()
+	if err != nil {
+		return err
+	}
+	defer C.git_signature_free(committerSig)
+
+	cmsg := C.CString(message)
+	defer C.free(unsafe.Pointer(cmsg))
+
+	cerr := C.git_rebase_commit(ID.toC(), rebase.ptr, authorSig, committerSig, nil, cmsg)
+	if cerr < 0 {
+		return MakeGitError(cerr)
+	}
+
+	return nil
+}
+
+// Finish finishes a rebase that is currently in progress once all patches have been applied.
+func (rebase *Rebase) Finish() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	err := C.git_rebase_finish(rebase.ptr, nil)
+	if err < 0 {
+		return MakeGitError(err)
+	}
+
+	return nil
+}
+
+// Abort aborts a rebase that is currently in progress, resetting the repository and working directory to their state before rebase began.
+func (rebase *Rebase) Abort() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	err := C.git_rebase_abort(rebase.ptr)
+	if err < 0 {
+		return MakeGitError(err)
+	}
+	return nil
+}
+
+// Free frees the Rebase object.
+func (rebase *Rebase) Free() {
+	runtime.SetFinalizer(rebase, nil)
+	C.git_rebase_free(rebase.ptr)
+}
+
+func newRebaseFromC(ptr *C.git_rebase) *Rebase {
+	rebase := &Rebase{ptr: ptr}
+	runtime.SetFinalizer(rebase, (*Rebase).Free)
+	return rebase
+}

rebase_test.go

@@ -0,0 +1,381 @@
+package git
+
+import (
+	"errors"
+	"strconv"
+	"testing"
+	"time"
+)
+
+// Tests
+
+func TestRebaseAbort(t *testing.T) {
+	// TEST DATA
+
+	// Inputs
+	branchName := "emile"
+	masterCommit := "something"
+	emileCommits := []string{
+		"fou",
+		"barre",
+	}
+
+	// Outputs
+	expectedHistory := []string{
+		"Test rebase, Baby! " + emileCommits[1],
+		"Test rebase, Baby! " + emileCommits[0],
+		"This is a commit\n",
+	}
+
+	// TEST
+	repo := createTestRepo(t)
+	defer cleanupTestRepo(t, repo)
+	seedTestRepo(t, repo)
+
+	// Setup a repo with 2 branches and a different tree
+	err := setupRepoForRebase(repo, masterCommit, branchName)
+	checkFatal(t, err)
+
+	// Create several commits in emile
+	for _, commit := range emileCommits {
+		_, err = commitSomething(repo, commit, commit)
+		checkFatal(t, err)
+	}
+
+	// Check history
+	actualHistory, err := commitMsgsList(repo)
+	checkFatal(t, err)
+	assertStringList(t, expectedHistory, actualHistory)
+
+	// Rebase onto master
+	rebase, err := performRebaseOnto(repo, "master")
+	checkFatal(t, err)
+	defer rebase.Free()
+
+	// Abort rebase
+	rebase.Abort()
+
+	// Check history is still the same
+	actualHistory, err = commitMsgsList(repo)
+	checkFatal(t, err)
+	assertStringList(t, expectedHistory, actualHistory)
+}
+
+func TestRebaseNoConflicts(t *testing.T) {
+	// TEST DATA
+
+	// Inputs
+	branchName := "emile"
+	masterCommit := "something"
+	emileCommits := []string{
+		"fou",
+		"barre",
+		"ouich",
+	}
+
+	// Outputs
+	expectedHistory := []string{
+		"Test rebase, Baby! " + emileCommits[2],
+		"Test rebase, Baby! " + emileCommits[1],
+		"Test rebase, Baby! " + emileCommits[0],
+		"Test rebase, Baby! " + masterCommit,
+		"This is a commit\n",
+	}
+
+	// TEST
+	repo := createTestRepo(t)
+	defer cleanupTestRepo(t, repo)
+	seedTestRepo(t, repo)
+
+	// Try to open existing rebase
+	oRebase, err := repo.OpenRebase(nil)
+	if err == nil {
+		t.Fatal("Did not expect to find a rebase in progress")
+	}
+
+	// Setup a repo with 2 branches and a different tree
+	err = setupRepoForRebase(repo, masterCommit, branchName)
+	checkFatal(t, err)
+
+	// Create several commits in emile
+	for _, commit := range emileCommits {
+		_, err = commitSomething(repo, commit, commit)
+		checkFatal(t, err)
+	}
+
+	// Rebase onto master
+	rebase, err := performRebaseOnto(repo, "master")
+	checkFatal(t, err)
+	defer rebase.Free()
+
+	// Open existing rebase
+	oRebase, err = repo.OpenRebase(nil)
+	checkFatal(t, err)
+	defer oRebase.Free()
+	if oRebase == nil {
+		t.Fatal("Expected to find an existing rebase in progress")
+	}
+
+	// Finish the rebase properly
+	err = rebase.Finish()
+	checkFatal(t, err)
+
+	// Check no more rebase is in progress
+	oRebase, err = repo.OpenRebase(nil)
+	if err == nil {
+		t.Fatal("Did not expect to find a rebase in progress")
+	}
+
+	// Check history is in correct order
+	actualHistory, err := commitMsgsList(repo)
+	checkFatal(t, err)
+	assertStringList(t, expectedHistory, actualHistory)
+
+}
+
+// Utils
+func setupRepoForRebase(repo *Repository, masterCommit, branchName string) error {
+	// Create a new branch from master
+	err := createBranch(repo, branchName)
+	if err != nil {
+		return err
+	}
+
+	// Create a commit in master
+	_, err = commitSomething(repo, masterCommit, masterCommit)
+	if err != nil {
+		return err
+	}
+
+	// Switch to emile
+	err = repo.SetHead("refs/heads/" + branchName)
+	if err != nil {
+		return err
+	}
+
+	// Check master commit is not in emile branch
+	if entryExists(repo, masterCommit) {
+		return errors.New(masterCommit + " entry should not exist in " + branchName + " branch.")
+	}
+
+	return nil
+}
+
+func performRebaseOnto(repo *Repository, branch string) (*Rebase, error) {
+	master, err := repo.LookupBranch(branch, BranchLocal)
+	if err != nil {
+		return nil, err
+	}
+	defer master.Free()
+
+	onto, err := repo.AnnotatedCommitFromRef(master.Reference)
+	if err != nil {
+		return nil, err
+	}
+	defer onto.Free()
+
+	// Init rebase
+	rebase, err := repo.InitRebase(nil, nil, onto, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	// Check no operation has been started yet
+	rebaseOperationIndex, err := rebase.CurrentOperationIndex()
+	if err == nil {
+		return nil, errors.New("No operation should have been started yet")
+	}
+
+	// Iterate in rebase operations regarding operation count
+	opCount := int(rebase.OperationCount())
+	for op := 0; op < opCount; op++ {
+		operation, err := rebase.Next()
+		if err != nil {
+			return nil, err
+		}
+
+		// Check operation index is correct
+		rebaseOperationIndex, err = rebase.CurrentOperationIndex()
+		if int(rebaseOperationIndex) != op {
+			return nil, errors.New("Bad operation index")
+		}
+		if !operationsAreEqual(rebase.OperationAt(uint(op)), operation) {
+			return nil, errors.New("Rebase operations should be equal")
+		}
+
+		// Get current rebase operation created commit
+		commit, err := repo.LookupCommit(operation.Id)
+		if err != nil {
+			return nil, err
+		}
+		defer commit.Free()
+
+		// Apply commit
+		err = rebase.Commit(operation.Id, signature(), signature(), commit.Message())
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return rebase, nil
+}
+
+func operationsAreEqual(l, r *RebaseOperation) bool {
+	return l.Exec == r.Exec && l.Type == r.Type && l.Id.String() == r.Id.String()
+}
+
+func createBranch(repo *Repository, branch string) error {
+	commit, err := headCommit(repo)
+	if err != nil {
+		return err
+	}
+	defer commit.Free()
+	_, err = repo.CreateBranch(branch, commit, false)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func signature() *Signature {
+	return &Signature{
+		Name:  "Emile",
+		Email: "emile@emile.com",
+		When:  time.Now(),
+	}
+}
+
+func headCommit(repo *Repository) (*Commit, error) {
+	head, err := repo.Head()
+	if err != nil {
+		return nil, err
+	}
+	defer head.Free()
+
+	commit, err := repo.LookupCommit(head.Target())
+	if err != nil {
+		return nil, err
+	}
+
+	return commit, nil
+}
+
+func headTree(repo *Repository) (*Tree, error) {
+	headCommit, err := headCommit(repo)
+	if err != nil {
+		return nil, err
+	}
+	defer headCommit.Free()
+
+	tree, err := headCommit.Tree()
+	if err != nil {
+		return nil, err
+	}
+
+	return tree, nil
+}
+
+func commitSomething(repo *Repository, something, content string) (*Oid, error) {
+	headCommit, err := headCommit(repo)
+	if err != nil {
+		return nil, err
+	}
+	defer headCommit.Free()
+
+	index, err := NewIndex()
+	if err != nil {
+		return nil, err
+	}
+	defer index.Free()
+
+	blobOID, err := repo.CreateBlobFromBuffer([]byte(content))
+	if err != nil {
+		return nil, err
+	}
+
+	entry := &IndexEntry{
+		Mode: FilemodeBlob,
+		Id:   blobOID,
+		Path: something,
+	}
+
+	if err := index.Add(entry); err != nil {
+		return nil, err
+	}
+
+	newTreeOID, err := index.WriteTreeTo(repo)
+	if err != nil {
+		return nil, err
+	}
+
+	newTree, err := repo.LookupTree(newTreeOID)
+	if err != nil {
+		return nil, err
+	}
+	defer newTree.Free()
+
+	if err != nil {
+		return nil, err
+	}
+	commit, err := repo.CreateCommit("HEAD", signature(), signature(), "Test rebase, Baby! "+something, newTree, headCommit)
+	if err != nil {
+		return nil, err
+	}
+
+	opts := &CheckoutOpts{
+		Strategy: CheckoutRemoveUntracked | CheckoutForce,
+	}
+	err = repo.CheckoutIndex(index, opts)
+	if err != nil {
+		return nil, err
+	}
+
+	return commit, nil
+}
+
+func entryExists(repo *Repository, file string) bool {
+	headTree, err := headTree(repo)
+	if err != nil {
+		return false
+	}
+	defer headTree.Free()
+
+	_, err = headTree.EntryByPath(file)
+
+	return err == nil
+}
+
+func commitMsgsList(repo *Repository) ([]string, error) {
+	head, err := headCommit(repo)
+	if err != nil {
+		return nil, err
+	}
+	defer head.Free()
+
+	var commits []string
+
+	parent := head.Parent(0)
+	defer parent.Free()
+	commits = append(commits, head.Message(), parent.Message())
+
+	for parent.ParentCount() != 0 {
+		parent = parent.Parent(0)
+		defer parent.Free()
+		commits = append(commits, parent.Message())
+	}
+
+	return commits, nil
+}
+
+func assertStringList(t *testing.T, expected, actual []string) {
+	if len(expected) != len(actual) {
+		t.Fatal("Lists are not the same size, expected " + strconv.Itoa(len(expected)) +
+			", got " + strconv.Itoa(len(actual)))
+	}
+	for index, element := range expected {
+		if element != actual[index] {
+			t.Error("Expected element " + strconv.Itoa(index) + " to be " + element + ", got " + actual[index])
+		}
+	}
+}