main: make configuration available when initializing commands

This, in principle, allows us to make use of configuration information
when we populate the Meta structure, though we won't actually make use
of that until a subsequent commit.

commands.go

@@ -25,15 +25,7 @@ const (
 	OutputPrefix = "o:"
 )
 
-func init() {
-	Ui = &cli.PrefixedUi{
-		AskPrefix:    OutputPrefix,
-		OutputPrefix: OutputPrefix,
-		InfoPrefix:   OutputPrefix,
-		ErrorPrefix:  ErrorPrefix,
-		Ui:           &cli.BasicUi{Writer: os.Stdout},
-	}
-
+func initCommands(config *Config) {
 	var inAutomation bool
 	if v := os.Getenv(runningInAutomationEnvName); v != "" {
 		inAutomation = true

main.go

@@ -96,6 +96,16 @@ func realMain() int {
 	return wrappedMain()
 }
 
+func init() {
+	Ui = &cli.PrefixedUi{
+		AskPrefix:    OutputPrefix,
+		OutputPrefix: OutputPrefix,
+		InfoPrefix:   OutputPrefix,
+		ErrorPrefix:  ErrorPrefix,
+		Ui:           &cli.BasicUi{Writer: os.Stdout},
+	}
+}
+
 func wrappedMain() int {
 	// We always need to close the DebugInfo before we exit.
 	defer terraform.CloseDebugInfo()
@@ -128,6 +138,11 @@ func wrappedMain() int {
 		config = *config.Merge(usrcfg)
 	}
 
+	// In tests, Commands may already be set to provide mock commands
+	if Commands == nil {
+		initCommands(&config)
+	}
+
 	// Run checkpoint
 	go runCheckpoint(&config)
 

main_test.go

@@ -18,9 +18,12 @@ func TestMain_cliArgsFromEnv(t *testing.T) {
 	defer func() { os.Args = oldArgs }()
 
 	// Setup test command and restore that
+	Commands = make(map[string]cli.CommandFactory)
+	defer func() {
+		Commands = nil
+	}()
 	testCommandName := "unit-test-cli-args"
 	testCommand := &testCommandCLI{}
-	defer func() { delete(Commands, testCommandName) }()
 	Commands[testCommandName] = func() (cli.Command, error) {
 		return testCommand, nil
 	}
@@ -150,6 +153,12 @@ func TestMain_cliArgsFromEnvAdvanced(t *testing.T) {
 	oldArgs := os.Args
 	defer func() { os.Args = oldArgs }()
 
+	// Setup test command and restore that
+	Commands = make(map[string]cli.CommandFactory)
+	defer func() {
+		Commands = nil
+	}()
+
 	cases := []struct {
 		Name     string
 		Command  string
@@ -230,7 +239,7 @@ func TestMain_cliArgsFromEnvAdvanced(t *testing.T) {
 			testCommand.Args = nil
 			exit := wrappedMain()
 			if (exit != 0) != tc.Err {
-				t.Fatalf("bad: %d", exit)
+				t.Fatalf("unexpected exit status %d; want 0", exit)
 			}
 			if tc.Err {
 				return