test: added tests to the cocommit program and also added a helper function in main to test

src/author.txt

@@ -1 +1 @@
-Syntax: name_short|Name|Username|email
+Syntax: name_short|Name|Username|email     !!Remember to set the env var authors_file!!

src/cocommit.go

@@ -0,0 +1,111 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"os/exec"
+	"regexp"
+	"strings"
+)
+
+type user struct {
+	username string
+	email    string
+}
+
+func main() {
+	users := make(map[string]user)
+
+	// Reads a shell env variable :: author_file
+	authors := os.Getenv("author_file")
+	
+	file, err := os.Open(authors)
+	if err != nil {
+		print("File not found")
+		os.Exit(2)
+	}
+	defer file.Close()
+	
+	scanner := bufio.NewScanner(file)
+	
+	// eat a single input
+	scanner.Scan()
+	
+	// reads the input of authors file and formats accordingly
+	for scanner.Scan() {
+		info := strings.Split(scanner.Text(), "|")
+		usr := user{username: info[2], email: info[3]}
+		users[info[0]] = usr
+		users[info[1]] = usr
+	}
+	
+	if err := scanner.Err(); err != nil {
+		os.Exit(2)
+	}
+	
+	args := os.Args[1:]
+
+	NoInput(args, users)
+	
+	
+	// builds the commit message with the selected authors
+	var sb strings.Builder
+	sb.WriteString(string(args[0])+"\n")
+	reg, _ := regexp.Compile("([^:]+):(.+)")
+
+	for _, commiter := range args[1:] {
+		if _, ok := users[commiter]; ok {
+			sb.WriteString("\nCo-authored-by: ")
+			sb.WriteString(users[commiter].username)
+			sb.WriteString(" <")
+			sb.WriteString(users[commiter].email)
+			sb.WriteRune('>')
+		} else if match := reg.MatchString(commiter); match {
+			str := strings.Split(commiter, ":")
+
+			sb.WriteString("\nCo-authored-by: ")
+			sb.WriteString(str[0])
+			sb.WriteString(" <")
+			sb.WriteString(str[1])
+			sb.WriteRune('>')
+
+		} else {
+			println(commiter, " was unknown. User either not defined or name typed wrong")
+		}
+	}
+	// commit msg built
+	commit := sb.String()
+	
+	// commit shell command
+	cmd := exec.Command("git", "commit", "-m", commit)
+
+	// https://stackoverflow.com/questions/18159704/how-to-debug-exit-status-1-error-when-running-exec-command-in-golang
+	
+	cmd_output, err := cmd.CombinedOutput()
+
+	if err != nil {
+		println(fmt.Sprint(err) + " : " + string(cmd_output))
+	} else {
+		println(string(cmd_output))
+	}
+
+}
+
+//TODO: move half this into another function and call before building users to improve performance
+func NoInput(args []string, users map[string]user) {
+	if len(args) < 2 {
+		// If you call binary with users prints users
+		if len(args) == 1 && args[0] == "users" {
+			println("List of users:")
+			for name, usr := range users {
+				println(name, " ->", " Username:", usr.username, " Email:", usr.email)
+			}
+			os.Exit(1)
+		}
+		// if calling binary with nothing or only string 
+		print("Usage: cocommit <commit message> <co-author1> [co-author2] [co-author3] || \n cocommit <commit message> <co-author1:email> [co-author2:email] [co-author3:email] || Mixes of both")
+		
+		os.Exit(1)
+	}
+}

src/cocommit_test.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"os"
+	"os/exec"
+	"testing"
+)
+
+func Test_emptyInput(t *testing.T) {
+	authors := make(map[string]user)
+	authors["test"] = user{username: "test", email: "test"} 
+	if os.Getenv("BE_CRASHER") == "1" {
+        NoInput([]string{}, authors)
+        return
+    }
+    cmd := exec.Command(os.Args[0], "-test.run=Test_emptyInput")
+    cmd.Env = append(os.Environ(), "BE_CRASHER=1")
+    err := cmd.Run()
+    if e, ok := err.(*exec.ExitError); ok && !e.Success() {
+        return
+    }
+    t.Fatalf("process ran with err %v, want exit status 1", err)
+}
+
+func Test_usersInput(t *testing.T) {
+	authors := make(map[string]user)
+	authors["test"] = user{username: "test", email: "test"} 
+	if os.Getenv("BE_CRASHER") == "1" {
+        NoInput([]string{"users"}, authors)
+        return
+    }
+    cmd := exec.Command(os.Args[0], "-test.run=Test_usersInput")
+    cmd.Env = append(os.Environ(), "BE_CRASHER=1")
+    err := cmd.Run()
+    if e, ok := err.(*exec.ExitError); ok && !e.Success() {
+        return
+    }
+    t.Fatalf("process ran with err %v, want exit status 1", err)
+}
+
+
+
+