feat: add the ability to use the latest or latest prerelease version …

…of Terraform installed

cmd/use.go

@@ -9,26 +9,50 @@ import (
 )
 
 const (
-	useExample = "# Activate a specific Terraform version\n" +
-		"tfversion use 1.7.3"
+	useExample = "# Use a specific Terraform version\n" +
+		"tfversion use 1.7.3" +
+		"\n" +
+		"\n" +
+		"# Use the latest stable Terraform version\n" +
+		"tfversion use --latest" +
+		"\n" +
+		"\n" +
+		"# Use the latest pre-release Terraform version\n" +
+		"tfversion use --latest --pre-release"
 )
 
 var (
 	useCmd = &cobra.Command{
 		Use:     "use",
 		Short:   "Activates a given Terraform version",
 		Example: useExample,
+		PreRun: func(cmd *cobra.Command, args []string) {
+			if preRelease && !latest {
+				cmd.MarkFlagRequired("latest")
+			}
+		},
 		Run: func(cmd *cobra.Command, args []string) {
-			if len(args) != 1 {
-				fmt.Println("error: provide a Terraform version to activate")
-				fmt.Println("See 'tfversion use -h' for help and examples")
-				os.Exit(1)
+			if latest {
+				if len(args) != 0 {
+					fmt.Println("error: 'latest' flag does not require specifying a Terraform version")
+					fmt.Println("See 'tfversion use -h' for help and examples")
+					os.Exit(1)
+				}
+				use.UseVersion("", latest, preRelease)
+			} else {
+				if len(args) != 1 {
+					fmt.Println("error: provide a Terraform version to activate")
+					fmt.Println("See 'tfversion use -h' for help and examples")
+					os.Exit(1)
+				}
+				use.UseVersion(args[0], latest, preRelease)
 			}
-			use.UseVersion(args[0])
 		},
 	}
 )
 
 func init() {
 	rootCmd.AddCommand(useCmd)
+	useCmd.Flags().BoolVar(&latest, "latest", false, "use the latest stable Terraform version")
+	useCmd.Flags().BoolVar(&preRelease, "pre-release", false, "When used with --latest, use the latest pre-release version")
 }

pkg/use/use.go

@@ -7,9 +7,26 @@ import (
 	"strings"
 
 	"github.com/tfversion/tfversion/pkg/download"
+	"github.com/tfversion/tfversion/pkg/list"
 )
 
-func UseVersion(version string) {
+// UseVersion activates the specified Terraform version or one of the latest versions
+func UseVersion(version string, latest bool, preRelease bool) {
+	// Get the available Terraform versions
+	versions := list.GetAvailableVersions()
+
+	// Set the version to the latest stable version if the `latest` flag is set
+	// or to the latest pre-release version if the `latest` and `pre-release` flags are set
+	if latest {
+		for _, v := range versions {
+			if !preRelease && list.IsPreReleaseVersion(v) {
+				continue
+			}
+			version = v
+			break
+		}
+	}
+
 	if !download.IsAlreadyDownloaded(version) {
 		fmt.Printf("Terraform version %s is not installed\n", version)
 		os.Exit(0)