fix: deprecations

go.go

@@ -132,34 +132,6 @@ func GoRoot() (string, error) {
 	return strings.TrimSpace(output), nil
 }
 
-// GoVersion reads the version of `go` that is on the PATH. This is done
-// instead of `runtime.Version()` because it is possible to run gox against
-// another Go version.
-func GoVersion() (string, error) {
-	// NOTE: We use `go run` instead of `go version` because the output
-	// of `go version` might change whereas the source is guaranteed to run
-	// for some time thanks to Go's compatibility guarantee.
-
-	td, err := os.MkdirTemp("", "gox")
-	if err != nil {
-		return "", err
-	}
-	defer os.RemoveAll(td)
-
-	// Write the source code for the program that will generate the version
-	sourcePath := filepath.Join(td, "version.go")
-	if err := os.WriteFile(sourcePath, []byte(versionSource), 0644); err != nil {
-		return "", err
-	}
-
-	// Execute and read the version, which will be the only thing on stdout.
-	version, err := execGo(gobin, nil, "", "run", sourcePath)
-
-	fmt.Printf("Detected Go Version: %s\n", version)
-
-	return version, err
-}
-
 // GoVersionParts parses the version numbers from the version itself
 // into major and minor: 1.5, 1.4, etc.
 func GoVersionParts() (result [2]int, err error) {

meta.go

@@ -0,0 +1,3 @@
+package main
+
+const metaVersion = "1.1.1"

version.go

@@ -1,3 +1,38 @@
+//go:build go1.16
+// +build go1.16
+
 package main
 
-const metaVersion = "1.1.1"
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+// GoVersion reads the version of `go` that is on the PATH. This is done
+// instead of `runtime.Version()` because it is possible to run gox against
+// another Go version.
+func GoVersion() (string, error) {
+	// NOTE: We use `go run` instead of `go version` because the output
+	// of `go version` might change whereas the source is guaranteed to run
+	// for some time thanks to Go's compatibility guarantee.
+
+	td, err := os.MkdirTemp("", "gox")
+	if err != nil {
+		return "", err
+	}
+	defer os.RemoveAll(td)
+
+	// Write the source code for the program that will generate the version
+	sourcePath := filepath.Join(td, "version.go")
+	if err := os.WriteFile(sourcePath, []byte(versionSource), 0644); err != nil {
+		return "", err
+	}
+
+	// Execute and read the version, which will be the only thing on stdout.
+	version, err := execGo(gobin, nil, "", "run", sourcePath)
+
+	fmt.Printf("Detected Go Version: %s\n", version)
+
+	return version, err
+}

version_legacy.go

@@ -0,0 +1,38 @@
+//go:build !go1.16
+// +build !go1.16
+
+package main
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+// GoVersion reads the version of `go` that is on the PATH. This is done
+// instead of `runtime.Version()` because it is possible to run gox against
+// another Go version.
+func GoVersion() (string, error) {
+	// NOTE: We use `go run` instead of `go version` because the output
+	// of `go version` might change whereas the source is guaranteed to run
+	// for some time thanks to Go's compatibility guarantee.
+
+	td, err := ioutil.TempDir("", "gox")
+	if err != nil {
+		return "", err
+	}
+	defer os.RemoveAll(td)
+
+	// Write the source code for the program that will generate the version
+	sourcePath := filepath.Join(td, "version.go")
+	if err := ioutil.WriteFile(sourcePath, []byte(versionSource), 0644); err != nil {
+		return "", err
+	}
+
+	// Execute and read the version, which will be the only thing on stdout.
+	version, err := execGo(gobin, nil, "", "run", sourcePath)
+
+	fmt.Printf("Detected Go Version: %s\n", version)
+
+	return version, err
+}