code that works

pkg/env/env.go

@@ -0,0 +1,107 @@
+package env
+
+import (
+	"os"
+	"regexp"
+	"runtime"
+	"strings"
+)
+
+// GetEditor gets the configured editor by checking environmental
+// variables EDITOR and VISUAL
+func GetEditor() string {
+	var editor string
+	if os.Getenv("EDITOR") != "" {
+		editor = os.Getenv("EDITOR")
+	} else if os.Getenv("VISUAL") != "" {
+		editor = os.Getenv("VISUAL")
+	} /* else {
+		// TODO: maybe pick something based on the OS
+	} */
+
+	return editor
+}
+
+// GetConfigDir gets a config directory based from environmental variables + the app name
+//
+// On Windows, %APPDATA%\agedit is used
+//
+// On UNIX-like systems, $XDG_CONFIG_HOME/agedit is tried, if it isn't defined, $HOME/.config/agedit is used
+func GetConfigDir(appname string) string {
+	var configdir string
+	switch runtime.GOOS {
+	case "windows":
+		configdir = os.Getenv("APPDATA")
+	default:
+		fallthrough
+	case "darwin":
+		// TODO: figure out the proper Mac OS local directories
+		fallthrough
+	case "linux":
+		if confighome := os.Getenv("XDG_CONFIG_HOME"); confighome != "" {
+			configdir = confighome
+		} else {
+			configdir = make_path(os.Getenv("HOME"), ".config")
+		}
+	}
+
+	return make_path(configdir, appname)
+}
+
+// GetConfigDir gets a config directory based from environmental variables + the app name
+//
+// On Windows, %LOCALAPPDATA%\agedit is used
+//
+// On UNIX-like systems, $XDG_DATA_HOME/agedit is tried, if it isn't defined, $HOME/.local/share/agedit is used
+func GetDataDir(appname string) string {
+	var datadir string
+	switch runtime.GOOS {
+	case "windows":
+		datadir = os.Getenv("LOCALAPPDATA")
+	default:
+		fallthrough
+	case "darwin":
+		// TODO: also here
+		fallthrough
+	case "linux":
+		if datahome := os.Getenv("XDG_DATA_HOME"); datahome != "" {
+			datadir = datahome
+		} else {
+			datadir = make_path(os.Getenv("HOME"), "local", "share")
+		}
+	}
+
+	return make_path(datadir, appname)
+}
+
+// GetTempDirectory returns the systems temporary directory
+//
+// returns %TEMP% on Windows, /tmp on UNIX-like systems
+func GetTempDirectory() string {
+	switch runtime.GOOS {
+	case "windows":
+		return os.Getenv("TEMP")
+	default:
+		fallthrough
+	case "darwin":
+		fallthrough
+	case "linux":
+		return "/tmp"
+	}
+}
+
+func make_path(paths ...string) string {
+	sep := string(os.PathSeparator)
+	output := strings.Builder{}
+
+	// add / to the start if it's not already there and we're not on Windows
+	if match, err := regexp.Match("^\\w", []byte(paths[0])); err == nil && match && runtime.GOOS != "windows" {
+		output.WriteString(sep)
+	}
+
+	for _, path := range paths {
+		output.WriteString(path + sep)
+	}
+
+	return output.String()
+}

pkg/env/env_test.go

@@ -0,0 +1,30 @@
+package env
+
+import (
+	"os"
+	"testing"
+)
+
+var (
+	editors = []string{"hx", "nano", "vi", "vim", "nvim", "micro", "emacs", "ed"}
+)
+
+func clearEnvForNow() {
+	for _, item := range []string{"EDITOR", "VISUAL"} {
+		os.Setenv(item, "")
+	}
+}
+
+func TestEditorFromEnv(t *testing.T) {
+	for _, item := range []string{"EDITOR", "VISUAL"} {
+		clearEnvForNow()
+		for _, editor := range editors {
+			if err := os.Setenv(item, editor); err != nil {
+				t.Fatal(err)
+			}
+			if got := GetEditor(); got != editor {
+				t.Fatal("got", got, "but wanted", editor)
+			}
+		}
+	}
+}