Adding \getenv metacommand

Author: kenshaw

drivers/completer/completer.go

@@ -124,14 +124,15 @@ func NewDefaultCompleter(opts ...Option) readline.AutoCompleter {
 			`\?`,
 			`\a`,
 			`\begin`,
+			`\bind`,
 			`\c`,
-			`\connect`,
 			`\C`,
 			`\cd`,
 			`\commit`,
+			`\connect`,
 			`\conninfo`,
-			`\copyright`,
 			`\copy`,
+			`\copyright`,
 			`\d+`,
 			`\da+`,
 			`\da`,
@@ -172,6 +173,7 @@ func NewDefaultCompleter(opts ...Option) readline.AutoCompleter {
 			`\echo`,
 			`\f`,
 			`\g`,
+			`\getenv`,
 			`\gexec`,
 			`\gset`,
 			`\gx`,

metacmd/cmds.go

@@ -420,6 +420,29 @@ func init() {
 				return os.Setenv(n, v)
 			},
 		},
+		GetEnv: {
+			Section: SectionOperatingSystem,
+			Name:    "getenv",
+			Desc:    Desc{"fetch environment variable", "VARNAME ENVVAR"},
+			Process: func(p *Params) error {
+				n, err := p.Get(true)
+				switch {
+				case err != nil:
+					return err
+				case n == "":
+					return text.ErrMissingRequiredArgument
+				}
+				v, err := p.Get(true)
+				switch {
+				case err != nil:
+					return err
+				case v == "":
+					return text.ErrMissingRequiredArgument
+				}
+				value, _ := env.Getenv(v)
+				return env.Set(n, value)
+			},
+		},
 		Timing: {
 			Section: SectionOperatingSystem,
 			Name:    "timing",

metacmd/metacmd.go

@@ -68,6 +68,8 @@ const (
 	ChangeDir
 	// SetEnv is the system set environment variable meta command (\setenv).
 	SetEnv
+	// GetEnv is the system get environment variable meta command (\getenv).
+	GetEnv
 	// Shell is the system shell exec meta command (\!).
 	Shell
 	// Out is the switch output meta command (\o).