Lua: Add function that returns the output of a process

Change-Id: I6863926a4da90adc89d96d47da1542c886b44040
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>

src/plugins/lua/bindings/qtcprocess.cpp

@@ -29,11 +29,22 @@ void addProcessModule()
                 p->setEnvironment(Environment::systemEnvironment());
 
                 QObject::connect(p, &Process::done, guard, [p, cb]() { cb(p->exitCode()); });
+            };
+
+        process["commandOutput_cb"] =
+            [guard
+             = pluginSpec->connectionGuard.get()](const QString &cmdline, const sol::function &cb) {
+                Process *p = new Process;
+                p->setCommand(CommandLine::fromUserInput((cmdline)));
+                p->setEnvironment(Environment::systemEnvironment());
+
+                QObject::connect(p, &Process::done, guard, [p, cb]() { cb(p->allOutput()); });
 
                 p->start();
             };
 
         process["runInTerminal"] = wrap(process["runInTerminal_cb"]);
+        process["commandOutput"] = wrap(process["commandOutput_cb"]);
 
         return process;
     });

src/plugins/lua/meta/process.lua

@@ -8,4 +8,10 @@ local process = {}
 ---@return number The exit code of the command
 function process.runInTerminal(cmd) end
 
+---@async
+---Runs a command and returns the output!
+---@param cmd string The command to run
+---@return string The output of the command
+function process.commandOutput(cmd) end
+
 return process