⚡ improve find terraform bin path

Avoid lookup into all Path directories and sub-directories when searching for terraform bin location when specify it on command line

lib/install.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"os/exec"
 	"os/user"
 	"path/filepath"
 	"runtime"
@@ -26,27 +27,32 @@ var (
 )
 
 // initialize : removes existing symlink to terraform binary// I Don't think this is needed
-func initialize() {
-
+func initialize(customBinPath string) {
 	/* Step 1 */
 	/* initilize default binary path for terraform */
 	/* assumes that terraform is installed here */
 	/* we will find the terraform path instalation later and replace this variable with the correct installed bin path */
 	installedBinPath := "/usr/local/bin/terraform"
 
-	/* find terraform binary location if terraform is already installed*/
-	cmd := NewCommand("terraform")
-	next := cmd.Find()
-
-	/* overrride installation default binary path if terraform is already installed */
-	/* find the last bin path */
-	for path := next(); len(path) > 0; path = next() {
+	// Try Custom installation path
+	path, err := exec.LookPath(customBinPath)
+
+	if err != nil {
+		/* find terraform binary location if terraform is already installed*/
+		cmd := NewCommand("terraform")
+		next := cmd.Find()
+		/* overrride installation default binary path if terraform is already installed */
+		/* find the last bin path */
+		for path := next(); len(path) > 0; path = next() {
+			installedBinPath = path
+		}
+	} else {
+		// override installation binary path with custom one specified in command line
 		installedBinPath = path
 	}
 
 	/* check if current symlink to terraform binary exist */
 	symlinkExist := CheckSymlink(installedBinPath)
-
 	/* remove current symlink if exist*/
 	if symlinkExist {
 		RemoveSymlink(installedBinPath)
@@ -75,9 +81,8 @@ func GetInstallLocation() string {
 
 }
 
-//Install : Install the provided version in the argument
+// Install : Install the provided version in the argument
 func Install(tfversion string, binPath string, mirrorURL string) {
-
 	// if !ValidVersionFormat(tfversion) {
 	// 	fmt.Printf("The provided terraform version format does not exist - %s. Try `tfswitch -l` to see all available versions.\n", tfversion)
 	// 	os.Exit(1)
@@ -89,8 +94,7 @@ func Install(tfversion string, binPath string, mirrorURL string) {
 	 * Tell users to add $HOME/bin to their path
 	 */
 	binPath = InstallableBinLocation(binPath)
-
-	initialize()                           //initialize path
+	initialize(binPath) //initialize path
 	installLocation = GetInstallLocation() //get installation location -  this is where we will put our terraform binary file
 
 	goarch := runtime.GOARCH
@@ -252,15 +256,15 @@ func GetRecentVersions() ([]string, error) {
 	return nil, nil
 }
 
-//CreateRecentFile : create a recent file
+// CreateRecentFile : create a recent file
 func CreateRecentFile(requestedVersion string) {
 
 	installLocation = GetInstallLocation() //get installation location -  this is where we will put our terraform binary file
 
 	WriteLines([]string{requestedVersion}, filepath.Join(installLocation, recentFile))
 }
 
-//ConvertExecutableExt : convert excutable with local OS extension
+// ConvertExecutableExt : convert excutable with local OS extension
 func ConvertExecutableExt(fpath string) string {
 	switch runtime.GOOS {
 	case "windows":
@@ -273,8 +277,8 @@ func ConvertExecutableExt(fpath string) string {
 	}
 }
 
-//InstallableBinLocation : Checks if terraform is installable in the location provided by the user.
-//If not, create $HOME/bin. Ask users to add  $HOME/bin to $PATH and return $HOME/bin as install location
+// InstallableBinLocation : Checks if terraform is installable in the location provided by the user.
+// If not, create $HOME/bin. Ask users to add  $HOME/bin to $PATH and return $HOME/bin as install location
 func InstallableBinLocation(userBinPath string) string {
 
 	usr, errCurr := user.Current()