From 0a042b66e59702e149f85419b4cd6201e269aaca Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Enver=20Bi=C5=A1evac?= <enver.bisevac@harness.io>
Date: Wed, 25 Dec 2024 13:22:48 +0000
Subject: [PATCH] feat: [code-2984]: fix datarace on branch and tag counts,
 improved cmd package with mutex (#3202)

* requested changes
* fix datarace on beanch and tag counts, improved cmd package with mux
---
 git/api/branch.go      | 24 ++++++++++++++----------
 git/api/tag.go         | 16 +++++++++-------
 git/command/command.go | 16 +++++++++++++---
 3 files changed, 36 insertions(+), 20 deletions(-)

diff --git a/git/api/branch.go b/git/api/branch.go
index bb8f7af6b..59e7d4dde 100644
--- a/git/api/branch.go
+++ b/git/api/branch.go
@@ -131,25 +131,29 @@ func (g *Git) GetBranchCount(
 		command.WithFlag("--format=%(refname:short)"),
 	)
 
-	var err error
 	go func() {
-		defer pipeIn.Close()
-		err = cmd.Run(ctx, command.WithDir(repoPath), command.WithStdout(pipeIn))
+		err := cmd.Run(ctx, command.WithDir(repoPath), command.WithStdout(pipeIn))
+		if err != nil {
+			_ = pipeIn.CloseWithError(
+				processGitErrorf(err, "failed to trigger branch command"),
+			)
+			return
+		}
+		_ = pipeIn.Close()
 	}()
-	if err != nil {
-		return 0, processGitErrorf(err, "failed to trigger branch command")
-	}
 
-	return countLines(pipeOut), nil
+	return countLines(pipeOut)
 }
 
-func countLines(pipe io.Reader) int {
+func countLines(pipe io.Reader) (int, error) {
 	scanner := bufio.NewScanner(pipe)
 	count := 0
 
 	for scanner.Scan() {
 		count++
 	}
-
-	return count
+	if err := scanner.Err(); err != nil {
+		return 0, err
+	}
+	return count, nil
 }
diff --git a/git/api/tag.go b/git/api/tag.go
index c752eb464..9fdfb0227 100644
--- a/git/api/tag.go
+++ b/git/api/tag.go
@@ -412,14 +412,16 @@ func (g *Git) GetTagCount(
 
 	cmd := command.New("tag")
 
-	var err error
 	go func() {
-		defer pipeIn.Close()
-		err = cmd.Run(ctx, command.WithDir(repoPath), command.WithStdout(pipeIn))
+		err := cmd.Run(ctx, command.WithDir(repoPath), command.WithStdout(pipeIn))
+		if err != nil {
+			_ = pipeIn.CloseWithError(
+				processGitErrorf(err, "failed to trigger tag command"),
+			)
+			return
+		}
+		_ = pipeIn.Close()
 	}()
-	if err != nil {
-		return 0, processGitErrorf(err, "failed to trigger branch command")
-	}
 
-	return countLines(pipeOut), nil
+	return countLines(pipeOut)
 }
diff --git a/git/command/command.go b/git/command/command.go
index 62f3e13c5..80060a900 100644
--- a/git/command/command.go
+++ b/git/command/command.go
@@ -22,6 +22,7 @@ import (
 	"io"
 	"os/exec"
 	"regexp"
+	"sync"
 )
 
 var (
@@ -65,6 +66,8 @@ type Command struct {
 	// internal counter for GIT_CONFIG_COUNT environment variable.
 	// more info: [link](https://git-scm.com/docs/git-config#Documentation/git-config.txt-GITCONFIGCOUNT)
 	configEnvCounter int
+
+	mux sync.RWMutex
 }
 
 // New creates new command for interacting with the git process.
@@ -74,15 +77,16 @@ func New(name string, options ...CmdOptionFunc) *Command {
 		Envs: make(Envs),
 	}
 
-	for _, opt := range options {
-		opt(c)
-	}
+	c.Add(options...)
 
 	return c
 }
 
 // Clone clones the command object.
 func (c *Command) Clone() *Command {
+	c.mux.RLock()
+	defer c.mux.RUnlock()
+
 	globals := make([]string, len(c.Globals))
 	copy(globals, c.Globals)
 
@@ -113,6 +117,9 @@ func (c *Command) Clone() *Command {
 
 // Add appends given options to the command.
 func (c *Command) Add(options ...CmdOptionFunc) *Command {
+	c.mux.Lock()
+	defer c.mux.Unlock()
+
 	for _, opt := range options {
 		opt(c)
 	}
@@ -181,6 +188,9 @@ func (c *Command) Run(ctx context.Context, opts ...RunOptionFunc) (err error) {
 }
 
 func (c *Command) makeArgs() ([]string, error) {
+	c.mux.RLock()
+	defer c.mux.RUnlock()
+
 	var safeArgs []string
 
 	// add globals