src: Add a commands debug flag

This commit allows setting the `commands` flag to the `debug` option, in
order to have the engine write on the *debug* buffer the commands that are
being executed, along with their arguments.

src/command_manager.cc

@@ -9,6 +9,7 @@
 #include "utils.hh"
 #include "optional.hh"
 #include "containers.hh"
+#include "buffer_utils.hh"
 
 #include <algorithm>
 
@@ -443,6 +444,16 @@ void CommandManager::execute_single_command(CommandParameters params,
     if (command_it == m_commands.end())
         throw command_not_found(params[0]);
 
+    const DebugFlags debug_flags = context.options()["debug"].get<DebugFlags>();
+    if (debug_flags & DebugFlags::Commands)
+    {
+        String repr_parameters;
+
+        for (auto repr_param : param_view)
+            repr_parameters += " " + repr_param;
+        write_to_debug_buffer(format("command {}{}", params[0], repr_parameters));
+    }
+
     try
     {
         ParametersParser parameter_parser(param_view,

src/option.hh

@@ -41,17 +41,19 @@ enum class DebugFlags
     Shell    = 1 << 1,
     Profile  = 1 << 2,
     Keys     = 1 << 3,
+    Commands = 1 << 4,
 };
 
 constexpr bool with_bit_ops(Meta::Type<DebugFlags>) { return true; }
 
-constexpr Array<EnumDesc<DebugFlags>, 4> enum_desc(Meta::Type<DebugFlags>)
+constexpr Array<EnumDesc<DebugFlags>, 5> enum_desc(Meta::Type<DebugFlags>)
 {
     return { {
         { DebugFlags::Hooks, "hooks" },
         { DebugFlags::Shell, "shell" },
         { DebugFlags::Profile, "profile" },
-        { DebugFlags::Keys, "keys" }
+        { DebugFlags::Keys, "keys" },
+        { DebugFlags::Commands, "commands" },
     } };
 }