Support building and moving patches

WIP

pkg/commands/commit_list_builder.go

@@ -0,0 +1,295 @@
+package commands
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+
+	"github.com/fatih/color"
+	"github.com/jesseduffield/lazygit/pkg/i18n"
+	"github.com/jesseduffield/lazygit/pkg/utils"
+	"github.com/sirupsen/logrus"
+)
+
+// context:
+// here we get the commits from git log but format them to show whether they're
+// unpushed/pushed/merged into the base branch or not, or if they're yet to
+// be processed as part of a rebase (these won't appear in git log but we
+// grab them from the rebase-related files in the .git directory to show them
+
+// if we find out we need to use one of these functions in the git.go file, we
+// can just pull them out of here and put them there and then call them from in here
+
+// CommitListBuilder returns a list of Branch objects for the current repo
+type CommitListBuilder struct {
+	Log                 *logrus.Entry
+	GitCommand          *GitCommand
+	OSCommand           *OSCommand
+	Tr                  *i18n.Localizer
+	CherryPickedCommits []*Commit
+	DiffEntries         []*Commit
+}
+
+// NewCommitListBuilder builds a new commit list builder
+func NewCommitListBuilder(log *logrus.Entry, gitCommand *GitCommand, osCommand *OSCommand, tr *i18n.Localizer, cherryPickedCommits []*Commit, diffEntries []*Commit) (*CommitListBuilder, error) {
+	return &CommitListBuilder{
+		Log:                 log,
+		GitCommand:          gitCommand,
+		OSCommand:           osCommand,
+		Tr:                  tr,
+		CherryPickedCommits: cherryPickedCommits,
+		DiffEntries:         diffEntries,
+	}, nil
+}
+
+// GetCommits obtains the commits of the current branch
+func (c *CommitListBuilder) GetCommits() ([]*Commit, error) {
+	commits := []*Commit{}
+	var rebasingCommits []*Commit
+	rebaseMode, err := c.GitCommand.RebaseMode()
+	if err != nil {
+		return nil, err
+	}
+	if rebaseMode != "" {
+		// here we want to also prepend the commits that we're in the process of rebasing
+		rebasingCommits, err = c.getRebasingCommits(rebaseMode)
+		if err != nil {
+			return nil, err
+		}
+		if len(rebasingCommits) > 0 {
+			commits = append(commits, rebasingCommits...)
+		}
+	}
+
+	unpushedCommits := c.getUnpushedCommits()
+	log := c.getLog()
+
+	// now we can split it up and turn it into commits
+	for _, line := range utils.SplitLines(log) {
+		splitLine := strings.Split(line, " ")
+		sha := splitLine[0]
+		_, unpushed := unpushedCommits[sha]
+		status := map[bool]string{true: "unpushed", false: "pushed"}[unpushed]
+		commits = append(commits, &Commit{
+			Sha:           sha,
+			Name:          strings.Join(splitLine[1:], " "),
+			Status:        status,
+			DisplayString: strings.Join(splitLine, " "),
+		})
+	}
+	if rebaseMode != "" {
+		currentCommit := commits[len(rebasingCommits)]
+		blue := color.New(color.FgYellow)
+		youAreHere := blue.Sprintf("<-- %s ---", c.Tr.SLocalize("YouAreHere"))
+		currentCommit.Name = fmt.Sprintf("%s %s", youAreHere, currentCommit.Name)
+	}
+
+	commits, err = c.setCommitMergedStatuses(commits)
+	if err != nil {
+		return nil, err
+	}
+
+	commits, err = c.setCommitCherryPickStatuses(commits)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, commit := range commits {
+		for _, entry := range c.DiffEntries {
+			if entry.Sha == commit.Sha {
+				commit.Status = "selected"
+			}
+		}
+	}
+
+	return commits, nil
+}
+
+// getRebasingCommits obtains the commits that we're in the process of rebasing
+func (c *CommitListBuilder) getRebasingCommits(rebaseMode string) ([]*Commit, error) {
+	switch rebaseMode {
+	case "normal":
+		return c.getNormalRebasingCommits()
+	case "interactive":
+		return c.getInteractiveRebasingCommits()
+	default:
+		return nil, nil
+	}
+}
+
+func (c *CommitListBuilder) getNormalRebasingCommits() ([]*Commit, error) {
+	rewrittenCount := 0
+	bytesContent, err := ioutil.ReadFile(fmt.Sprintf("%s/rebase-apply/rewritten", c.GitCommand.DotGitDir))
+	if err == nil {
+		content := string(bytesContent)
+		rewrittenCount = len(strings.Split(content, "\n"))
+	}
+
+	// we know we're rebasing, so lets get all the files whose names have numbers
+	commits := []*Commit{}
+	err = filepath.Walk(fmt.Sprintf("%s/rebase-apply", c.GitCommand.DotGitDir), func(path string, f os.FileInfo, err error) error {
+		if rewrittenCount > 0 {
+			rewrittenCount--
+			return nil
+		}
+		if err != nil {
+			return err
+		}
+		re := regexp.MustCompile(`^\d+$`)
+		if !re.MatchString(f.Name()) {
+			return nil
+		}
+		bytesContent, err := ioutil.ReadFile(path)
+		if err != nil {
+			return err
+		}
+		content := string(bytesContent)
+		commit, err := c.commitFromPatch(content)
+		if err != nil {
+			return err
+		}
+		commits = append([]*Commit{commit}, commits...)
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return commits, nil
+}
+
+// git-rebase-todo example:
+// pick ac446ae94ee560bdb8d1d057278657b251aaef17 ac446ae
+// pick afb893148791a2fbd8091aeb81deba4930c73031 afb8931
+
+// git-rebase-todo.backup example:
+// pick 49cbba374296938ea86bbd4bf4fee2f6ba5cccf6 third commit on master
+// pick ac446ae94ee560bdb8d1d057278657b251aaef17 blah  commit on master
+// pick afb893148791a2fbd8091aeb81deba4930c73031 fourth commit on master
+
+// getInteractiveRebasingCommits takes our git-rebase-todo and our git-rebase-todo.backup files
+// and extracts out the sha and names of commits that we still have to go
+// in the rebase:
+func (c *CommitListBuilder) getInteractiveRebasingCommits() ([]*Commit, error) {
+	bytesContent, err := ioutil.ReadFile(fmt.Sprintf("%s/rebase-merge/git-rebase-todo", c.GitCommand.DotGitDir))
+	if err != nil {
+		c.Log.Info(fmt.Sprintf("error occurred reading git-rebase-todo: %s", err.Error()))
+		// we assume an error means the file doesn't exist so we just return
+		return nil, nil
+	}
+
+	commits := []*Commit{}
+	lines := strings.Split(string(bytesContent), "\n")
+	for _, line := range lines {
+		if line == "" || line == "noop" {
+			return commits, nil
+		}
+		splitLine := strings.Split(line, " ")
+		commits = append([]*Commit{{
+			Sha:    splitLine[1][0:7],
+			Name:   strings.Join(splitLine[2:], " "),
+			Status: "rebasing",
+			Action: splitLine[0],
+		}}, commits...)
+	}
+
+	return nil, nil
+}
+
+// assuming the file starts like this:
+// From e93d4193e6dd45ca9cf3a5a273d7ba6cd8b8fb20 Mon Sep 17 00:00:00 2001
+// From: Lazygit Tester <test@example.com>
+// Date: Wed, 5 Dec 2018 21:03:23 +1100
+// Subject: second commit on master
+func (c *CommitListBuilder) commitFromPatch(content string) (*Commit, error) {
+	lines := strings.Split(content, "\n")
+	sha := strings.Split(lines[0], " ")[1][0:7]
+	name := strings.TrimPrefix(lines[3], "Subject: ")
+	return &Commit{
+		Sha:    sha,
+		Name:   name,
+		Status: "rebasing",
+	}, nil
+}
+
+func (c *CommitListBuilder) setCommitMergedStatuses(commits []*Commit) ([]*Commit, error) {
+	ancestor, err := c.getMergeBase()
+	if err != nil {
+		return nil, err
+	}
+	if ancestor == "" {
+		return commits, nil
+	}
+	passedAncestor := false
+	for i, commit := range commits {
+		if strings.HasPrefix(ancestor, commit.Sha) {
+			passedAncestor = true
+		}
+		if commit.Status != "pushed" {
+			continue
+		}
+		if passedAncestor {
+			commits[i].Status = "merged"
+		}
+	}
+	return commits, nil
+}
+
+func (c *CommitListBuilder) setCommitCherryPickStatuses(commits []*Commit) ([]*Commit, error) {
+	for _, commit := range commits {
+		for _, cherryPickedCommit := range c.CherryPickedCommits {
+			if commit.Sha == cherryPickedCommit.Sha {
+				commit.Copied = true
+			}
+		}
+	}
+	return commits, nil
+}
+
+func (c *CommitListBuilder) getMergeBase() (string, error) {
+	currentBranch, err := c.GitCommand.CurrentBranchName()
+	if err != nil {
+		return "", err
+	}
+
+	baseBranch := "master"
+	if strings.HasPrefix(currentBranch, "feature/") {
+		baseBranch = "develop"
+	}
+
+	// swallowing error because it's not a big deal; probably because there are no commits yet
+	output, _ := c.OSCommand.RunCommandWithOutput(fmt.Sprintf("git merge-base HEAD %s", baseBranch))
+	return output, nil
+}
+
+// getUnpushedCommits Returns the sha's of the commits that have not yet been pushed
+// to the remote branch of the current branch, a map is returned to ease look up
+func (c *CommitListBuilder) getUnpushedCommits() map[string]bool {
+	pushables := map[string]bool{}
+	o, err := c.OSCommand.RunCommandWithOutput("git rev-list @{u}..HEAD --abbrev-commit")
+	if err != nil {
+		return pushables
+	}
+	for _, p := range utils.SplitLines(o) {
+		pushables[p] = true
+	}
+
+	return pushables
+}
+
+// getLog gets the git log (currently limited to 30 commits for performance
+// until we work out lazy loading
+func (c *CommitListBuilder) getLog() string {
+	// currently limiting to 30 for performance reasons
+	// TODO: add lazyloading when you scroll down
+	result, err := c.OSCommand.RunCommandWithOutput("git log --oneline -30")
+	if err != nil {
+		// assume if there is an error there are no commits yet for this branch
+		return ""
+	}
+
+	return result
+}