only process aliases when non-existent command passed

cmd/gh/main.go

@@ -32,10 +32,18 @@ func main() {
 
 	stderr := utils.NewColorable(os.Stderr)
 
-	expandedArgs, err := command.ExpandAlias(os.Args)
-	if err != nil {
-		fmt.Fprintf(stderr, "failed to process aliases:  %s\n", err)
-		os.Exit(2)
+	expandedArgs := []string{}
+	if len(os.Args) > 0 {
+		expandedArgs = os.Args[1:]
+	}
+
+	cmd, _, err := command.RootCmd.Traverse(expandedArgs)
+	if err != nil || cmd == command.RootCmd {
+		expandedArgs, err = command.ExpandAlias(os.Args)
+		if err != nil {
+			fmt.Fprintf(stderr, "failed to process aliases:  %s\n", err)
+			os.Exit(2)
+		}
 	}
 
 	command.RootCmd.SetArgs(expandedArgs)

command/alias.go

@@ -11,7 +11,7 @@ import (
 
 // TODO
 // - [ ] DEBUG support
-// - [ ] give our commands precedence
+// - [x] give our commands precedence
 // - [x] prevent overriding existing gh command
 // - [x] allow overwriting alias
 // - [x] forward extra arguments