fix: Avoid running shell twice in coder agent (#5061)

mafredri · web-flow · commit e72927f3ab1a · 2022-11-14T14:01:22.000+02:00
The users login shell would be executed as:

	/bin/bash -c '/bin/bash -l'

This simplifies the command for login shells so that the executed
command is:

	/bin/bash -l
diff --git a/agent/agent.go b/agent/agent.go
@@ -561,25 +561,26 @@ func (a *agent) createCommand(ctx context.Context, rawCommand string, env []stri
 		return nil, xerrors.Errorf("metadata is the wrong type: %T", metadata)
 	}
 
+	// OpenSSH executes all commands with the users current shell.
+	// We replicate that behavior for IDE support.
+	caller := "-c"
+	if runtime.GOOS == "windows" {
+		caller = "/c"
+	}
+	args := []string{caller, rawCommand}
+
 	// gliderlabs/ssh returns a command slice of zero
 	// when a shell is requested.
-	command := rawCommand
-	if len(command) == 0 {
-		command = shell
+	if len(rawCommand) == 0 {
+		args = []string{}
 		if runtime.GOOS != "windows" {
 			// On Linux and macOS, we should start a login
 			// shell to consume juicy environment variables!
-			command += " -l"
+			args = append(args, "-l")
 		}
 	}
 
-	// OpenSSH executes all commands with the users current shell.
-	// We replicate that behavior for IDE support.
-	caller := "-c"
-	if runtime.GOOS == "windows" {
-		caller = "/c"
-	}
-	cmd := exec.CommandContext(ctx, shell, caller, command)
+	cmd := exec.CommandContext(ctx, shell, args...)
 	cmd.Dir = metadata.Directory
 	if cmd.Dir == "" {
 		// Default to $HOME if a directory is not set!
