Do not include non-primitive option value in *SetOption hook filter

Only include the value for int/str/bool options, for the rest just
write '<option name>=...'.

This should reduce the cost of some patterns such as repeatedly adding
a value inside a list option.

It seems very unlikely that the actual value would be matched by
a hook regex string for non primitive types.

doc/pages/changelog.asciidoc

@@ -16,6 +16,10 @@ released versions.
 * `%val{...}` now expands to list of strings, `$kak_quoted_...` now work
   as expected with these.
 
+* `*SetOption` hooks filter string will contain a value only for options
+  of int/str/bool types to avoid performance issue with generating those
+  on more complex option types. 
+
 == Kakoune v2020.01.16
 
 * Expose history tree through `$kak_history` and

src/buffer.cc

@@ -685,7 +685,7 @@ void Buffer::on_option_changed(const Option& option)
             m_flags &= ~Flags::ReadOnly;
     }
     run_hook_in_own_context(Hook::BufSetOption,
-                            format("{}={}", option.name(), option.get_as_string(Quoting::Raw)));
+                            format("{}={}", option.name(), option.get_desc_string()));
 }
 
 void Buffer::run_hook_in_own_context(Hook hook, StringView param, String client_name)

src/option_manager.hh

@@ -55,6 +55,7 @@ public:
 
     virtual String get_as_string(Quoting quoting) const = 0;
     virtual Vector<String> get_as_strings() const = 0;
+    virtual String get_desc_string() const = 0;
     virtual void set_from_strings(ConstArrayView<String> strs) = 0;
     virtual void add_from_strings(ConstArrayView<String> strs) = 0;
     virtual void update(const Context& context) = 0;
@@ -154,6 +155,14 @@ public:
         return option_to_string(m_value, quoting);
     }
 
+    String get_desc_string() const override
+    {
+        if constexpr (std::is_same_v<int, T> or std::is_same_v<bool, T> or std::is_same_v<String, T>)
+            return option_to_string(m_value, Quoting::Raw);
+        else
+            return "...";
+    }
+
     void set_from_strings(ConstArrayView<String> strs) override
     {
         set(option_from_strings(Meta::Type<T>{}, strs));

src/scope.cc

@@ -19,7 +19,7 @@ void GlobalScope::on_option_changed(const Option& option)
 {
     Context empty_context{Context::EmptyContextFlag{}};
     hooks().run_hook(Hook::GlobalSetOption,
-                     format("{}={}", option.name(), option.get_as_string(Quoting::Raw)),
+                     format("{}={}", option.name(), option.get_desc_string()),
                      empty_context);
 }
 

src/window.cc

@@ -346,8 +346,7 @@ void Window::clear_display_buffer()
 
 void Window::on_option_changed(const Option& option)
 {
-    run_hook_in_own_context(Hook::WinSetOption, format("{}={}", option.name(),
-                                                   option.get_as_string(Quoting::Raw)));
+    run_hook_in_own_context(Hook::WinSetOption, format("{}={}", option.name(), option.get_desc_string()));
     // an highlighter might depend on the option, so we need to redraw
     force_redraw();
 }