factor out code from git.go

1 files changed, 381 insertions, 0 deletions

diff --git a/pkg/commands/loading_commits.go b/pkg/commands/loading_commits.go
new file mode 100644
index 000000000..d29e03a28
--- /dev/null
+++ b/pkg/commands/loading_commits.go
@@ -0,0 +1,381 @@
+package commands
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"github.com/fatih/color"
+	"github.com/jesseduffield/lazygit/pkg/commands/oscommands"
+	"github.com/jesseduffield/lazygit/pkg/i18n"
+	"github.com/jesseduffield/lazygit/pkg/models"
+	"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
+
+const SEPARATION_CHAR = "|"
+
+// CommitListBuilder returns a list of Branch objects for the current repo
+type CommitListBuilder struct {
+	Log        *logrus.Entry
+	GitCommand *GitCommand
+	OSCommand  *oscommands.OSCommand
+	Tr         *i18n.Localizer
+}
+
+// NewCommitListBuilder builds a new commit list builder
+func NewCommitListBuilder(log *logrus.Entry, gitCommand *GitCommand, osCommand *oscommands.OSCommand, tr *i18n.Localizer) *CommitListBuilder {
+	return &CommitListBuilder{
+		Log:        log,
+		GitCommand: gitCommand,
+		OSCommand:  osCommand,
+		Tr:         tr,
+	}
+}
+
+// extractCommitFromLine takes a line from a git log and extracts the sha, message, date, and tag if present
+// then puts them into a commit object
+// example input:
+// 8ad01fe32fcc20f07bc6693f87aa4977c327f1e1|10 hours ago|Jesse Duffield| (HEAD -> master, tag: v0.15.2)|refresh commits when adding a tag
+func (c *CommitListBuilder) extractCommitFromLine(line string) *models.Commit {
+	split := strings.Split(line, SEPARATION_CHAR)
+
+	sha := split[0]
+	unixTimestamp := split[1]
+	author := split[2]
+	extraInfo := strings.TrimSpace(split[3])
+	parentHashes := split[4]
+
+	message := strings.Join(split[5:], SEPARATION_CHAR)
+	tags := []string{}
+
+	if extraInfo != "" {
+		re := regexp.MustCompile(`tag: ([^,\)]+)`)
+		tagMatch := re.FindStringSubmatch(extraInfo)
+		if len(tagMatch) > 1 {
+			tags = append(tags, tagMatch[1])
+		}
+	}
+
+	unitTimestampInt, _ := strconv.Atoi(unixTimestamp)
+
+	// Any commit with multiple parents is a merge commit.
+	// If there's a space then it means there must be more than one parent hash
+	isMerge := strings.Contains(parentHashes, " ")
+
+	return &models.Commit{
+		Sha:           sha,
+		Name:          message,
+		Tags:          tags,
+		ExtraInfo:     extraInfo,
+		UnixTimestamp: int64(unitTimestampInt),
+		Author:        author,
+		IsMerge:       isMerge,
+	}
+}
+
+type GetCommitsOptions struct {
+	Limit                bool
+	FilterPath           string
+	IncludeRebaseCommits bool
+	RefName              string // e.g. "HEAD" or "my_branch"
+}
+
+func (c *CommitListBuilder) MergeRebasingCommits(commits []*models.Commit) ([]*models.Commit, error) {
+	// chances are we have as many commits as last time so we'll set the capacity to be the old length
+	result := make([]*models.Commit, 0, len(commits))
+	for i, commit := range commits {
+		if commit.Status != "rebasing" { // removing the existing rebase commits so we can add the refreshed ones
+			result = append(result, commits[i:]...)
+			break
+		}
+	}
+
+	rebaseMode, err := c.GitCommand.RebaseMode()
+	if err != nil {
+		return nil, err
+	}
+
+	if rebaseMode == "" {
+		// not in rebase mode so return original commits
+		return result, nil
+	}
+
+	rebasingCommits, err := c.getRebasingCommits(rebaseMode)
+	if err != nil {
+		return nil, err
+	}
+	if len(rebasingCommits) > 0 {
+		result = append(rebasingCommits, result...)
+	}
+
+	return result, nil
+}
+
+// GetCommits obtains the commits of the current branch
+func (c *CommitListBuilder) GetCommits(opts GetCommitsOptions) ([]*models.Commit, error) {
+	commits := []*models.Commit{}
+	var rebasingCommits []*models.Commit
+	rebaseMode, err := c.GitCommand.RebaseMode()
+	if err != nil {
+		return nil, err
+	}
+
+	if opts.IncludeRebaseCommits && opts.FilterPath == "" {
+		var err error
+		rebasingCommits, err = c.MergeRebasingCommits(commits)
+		if err != nil {
+			return nil, err
+		}
+		commits = append(commits, rebasingCommits...)
+	}
+
+	passedFirstPushedCommit := false
+	firstPushedCommit, err := c.getFirstPushedCommit(opts.RefName)
+	if err != nil {
+		// must have no upstream branch so we'll consider everything as pushed
+		passedFirstPushedCommit = true
+	}
+
+	cmd := c.getLogCmd(opts)
+
+	err = oscommands.RunLineOutputCmd(cmd, func(line string) (bool, error) {
+		if strings.Split(line, " ")[0] != "gpg:" {
+			commit := c.extractCommitFromLine(line)
+			if commit.Sha == firstPushedCommit {
+				passedFirstPushedCommit = true
+			}
+			commit.Status = map[bool]string{true: "unpushed", false: "pushed"}[!passedFirstPushedCommit]
+			commits = append(commits, commit)
+		}
+		return false, nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	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(opts.RefName, commits)
+	if err != nil {
+		return nil, err
+	}
+
+	return commits, nil
+}
+
+// getRebasingCommits obtains the commits that we're in the process of rebasing
+func (c *CommitListBuilder) getRebasingCommits(rebaseMode string) ([]*models.Commit, error) {
+	switch rebaseMode {
+	case "normal":
+		return c.getNormalRebasingCommits()
+	case "interactive":
+		return c.getInteractiveRebasingCommits()
+	default:
+		return nil, nil
+	}
+}
+
+func (c *CommitListBuilder) getNormalRebasingCommits() ([]*models.Commit, error) {
+	rewrittenCount := 0
+	bytesContent, err := ioutil.ReadFile(filepath.Join(c.GitCommand.DotGitDir, "rebase-apply/rewritten"))
+	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 := []*models.Commit{}
+	err = filepath.Walk(filepath.Join(c.GitCommand.DotGitDir, "rebase-apply"), 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([]*models.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() ([]*models.Commit, error) {
+	bytesContent, err := ioutil.ReadFile(filepath.Join(c.GitCommand.DotGitDir, "rebase-merge/git-rebase-todo"))
+	if err != nil {
+		c.Log.Error(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 := []*models.Commit{}
+	lines := strings.Split(string(bytesContent), "\n")
+	for _, line := range lines {
+		if line == "" || line == "noop" {
+			return commits, nil
+		}
+		if strings.HasPrefix(line, "#") {
+			continue
+		}
+		splitLine := strings.Split(line, " ")
+		commits = append([]*models.Commit{{
+			Sha:    splitLine[1],
+			Name:   strings.Join(splitLine[2:], " "),
+			Status: "rebasing",
+			Action: splitLine[0],
+		}}, commits...)
+	}
+
+	return commits, 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) (*models.Commit, error) {
+	lines := strings.Split(content, "\n")
+	sha := strings.Split(lines[0], " ")[1]
+	name := strings.TrimPrefix(lines[3], "Subject: ")
+	return &models.Commit{
+		Sha:    sha,
+		Name:   name,
+		Status: "rebasing",
+	}, nil
+}
+
+func (c *CommitListBuilder) setCommitMergedStatuses(refName string, commits []*models.Commit) ([]*models.Commit, error) {
+	ancestor, err := c.getMergeBase(refName)
+	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) getMergeBase(refName string) (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("git merge-base %s %s", refName, baseBranch)
+	return ignoringWarnings(output), nil
+}
+
+func ignoringWarnings(commandOutput string) string {
+	trimmedOutput := strings.TrimSpace(commandOutput)
+	split := strings.Split(trimmedOutput, "\n")
+	// need to get last line in case the first line is a warning about how the error is ambiguous.
+	// At some point we should find a way to make it unambiguous
+	lastLine := split[len(split)-1]
+
+	return lastLine
+}
+
+// getFirstPushedCommit returns the first commit SHA which has been pushed to the ref's upstream.
+// all commits above this are deemed unpushed and marked as such.
+func (c *CommitListBuilder) getFirstPushedCommit(refName string) (string, error) {
+	output, err := c.OSCommand.RunCommandWithOutput("git merge-base %s %s@{u}", refName, refName)
+	if err != nil {
+		return "", err
+	}
+
+	return ignoringWarnings(output), nil
+}
+
+// getLog gets the git log.
+func (c *CommitListBuilder) getLogCmd(opts GetCommitsOptions) *exec.Cmd {
+	limitFlag := ""
+	if opts.Limit {
+		limitFlag = "-300"
+	}
+
+	filterFlag := ""
+	if opts.FilterPath != "" {
+		filterFlag = fmt.Sprintf(" --follow -- %s", c.OSCommand.Quote(opts.FilterPath))
+	}
+
+	return c.OSCommand.ExecutableFromString(
+		fmt.Sprintf(
+			"git log %s --oneline --pretty=format:\"%%H%s%%at%s%%aN%s%%d%s%%p%s%%s\" %s --abbrev=%d --date=unix %s",
+			opts.RefName,
+			SEPARATION_CHAR,
+			SEPARATION_CHAR,
+			SEPARATION_CHAR,
+			SEPARATION_CHAR,
+			SEPARATION_CHAR,
+			limitFlag,
+			20,
+			filterFlag,
+		),
+	)
+}