Add a Config::is_in_list() method

src/config/config.cpp

@@ -1,10 +1,12 @@
 #include <config/config.hpp>
 #include <utils/tolower.hpp>
+#include <utils/split.hpp>
 
-#include <iostream>
-#include <cstring>
-
+#include <algorithm>
 #include <cstdlib>
+#include <cstring>
+#include <iostream>
+#include <vector>
 
 using namespace std::string_literals;
 
@@ -40,6 +42,15 @@ int Config::get_int(const std::string& option, const int& def)
     return def;
 }
 
+bool Config::is_in_list(const std::string& option, const std::string& value)
+{
+  std::string res = Config::get(option, "");
+  if (res.empty())
+    return false;
+  std::vector<std::string> list = utils::split(res, ':');
+  return std::find(list.cbegin(), list.cend(), value) != list.cend();
+}
+
 void Config::set(const std::string& option, const std::string& value, bool save)
 {
   Config::values[option] = value;

src/config/config.hpp

@@ -45,6 +45,11 @@ public:
    */
   static int get_int(const std::string&, const int&);
   static bool get_bool(const std::string&, const bool);
+  /**
+   * Returns true if value is present in a colon-separated list, otherwise
+   * false.
+   */
+  static bool is_in_list(const std::string& option, const std::string& value);
   /**
    * Set a value for the given option. And write all the config
    * in the file from which it was read if save is true.