Add object mode expansions

doc/pages/expansions.asciidoc

@@ -215,7 +215,7 @@ The following expansions are supported (with required context _in italics_):
     directory containing the user configuration
 
 *%val{count}*::
-    _in `map` command <keys> parameter_ +
+    _in `map` command <keys> parameter and `<a-;>` from object menu_ +
     current count when the mapping was triggered, defaults to 0 if no
     count given
 
@@ -262,14 +262,25 @@ The following expansions are supported (with required context _in italics_):
     _in buffer, window scope_ +
     `true` if the buffer has modifications not saved, otherwise `false`
 
+*%val{object_flags}*::
+    _for commands executed from the object menu's `<a-;>` only_ +
+    a pipe-separted list of words including `inner` if the user wants
+    an inner selection, `to_begin` if the user wants to select to the
+    beginning, and `to_end` if the user wants to select to the end
+
 *%val{register}*::
-    _in `map` command <keys> parameter_ +
+    _in `map` command <keys> parameter and `<a-;>` from the object menu_ +
     current register when the mapping was triggered
 
 *%val{runtime}*::
     directory containing the kak support files, determined from Kakoune's
     binary location
 
+*%val{select_mode}*::
+    _for commands executed from the object menu's `<a-;>` only_ +
+    `replace` if the new selection should replace the existing, `extend`
+    otherwise
+
 *%val{selection}*::
     _in window scope_ +
     content of the main selection

doc/pages/keys.asciidoc

@@ -682,8 +682,8 @@ in order to specify the wanted object:
     select user defined object, will prompt for open and close text
 
 *<a-;>*::
-    run a command in object context.  The expansions `%val{count}` and
-    `%val{register}` are available here.
+    run a command with additional expansions describing the selection
+    context (See <<expansions#,`:doc expansions`>>)
 
 == Prompt commands
 

src/normal.cc

@@ -9,6 +9,7 @@
 #include "commands.hh"
 #include "context.hh"
 #include "diff.hh"
+#include "enum.hh"
 #include "face_registry.hh"
 #include "file.hh"
 #include "flags.hh"
@@ -37,6 +38,14 @@ enum class SelectMode
     Append,
 };
 
+constexpr auto enum_desc(Meta::Type<SelectMode>)
+{
+    return make_array<EnumDesc<SelectMode>, 3>({
+        { SelectMode::Replace, "replace" },
+        { SelectMode::Extend, "extend" },
+        { SelectMode::Append, "append" },
+    });
+}
 void merge_selections(Selection& sel, const Selection& new_sel)
 {
     const bool forward = sel.cursor() >= sel.anchor();
@@ -437,7 +446,7 @@ void for_each_codepoint(Context& context, NormalParams)
     selections.insert(strings, InsertMode::Replace);
 }
 
-void command(Context& context, NormalParams params)
+void command(Context& context, EnvVarMap env_vars)
 {
     if (not CommandManager::has_instance())
         throw runtime_error{"commands are not supported"};
@@ -451,7 +460,7 @@ void command(Context& context, NormalParams params)
            StringView cmd_line, ByteCount pos) {
                return CommandManager::instance().complete(context, flags, cmd_line, pos);
         },
-        [params](StringView cmdline, PromptEvent event, Context& context) {
+        [env_vars = std::move(env_vars)](StringView cmdline, PromptEvent event, Context& context) {
             if (context.has_client())
             {
                 context.client().info_hide();
@@ -479,16 +488,21 @@ void command(Context& context, NormalParams params)
                 else if (not is_blank(cmdline[0]))
                     RegisterManager::instance()[':'].set(context, cmdline.str());
 
-                EnvVarMap env_vars = {
-                    { "count", to_string(params.count) },
-                    { "register", String{&params.reg, 1} }
-                };
                 CommandManager::instance().execute(
                     cmdline, context, { {}, env_vars });
             }
         });
 }
 
+void command(Context& context, NormalParams params)
+{
+    EnvVarMap env_vars = {
+        { "count", to_string(params.count) },
+        { "register", String{&params.reg, 1} }
+    };
+    command(context, std::move(env_vars));
+}
+
 BufferCoord apply_diff(Buffer& buffer, BufferCoord pos, StringView before, StringView after)
 {
     const auto lines_before = before | split_after<StringView>('\n') | gather<Vector<StringView>>();
@@ -1313,7 +1327,13 @@ void select_object(Context& context, NormalParams params)
 
         if (key == alt(';'))
         {
-            command(context, params);
+            EnvVarMap env_vars = {
+                { "count", to_string(params.count) },
+                { "register", String{&params.reg, 1} },
+                { "select_mode", option_to_string(mode) },
+                { "object_flags", option_to_string(flags) }
+            };
+            command(context, std::move(env_vars));
             return;
         }
 

src/selectors.hh

@@ -1,6 +1,7 @@
 #ifndef selectors_hh_INCLUDED
 #define selectors_hh_INCLUDED
 
+#include "enum.hh"
 #include "optional.hh"
 #include "meta.hh"
 #include "unicode.hh"
@@ -62,6 +63,15 @@ enum class ObjectFlags
 
 constexpr bool with_bit_ops(Meta::Type<ObjectFlags>) { return true; }
 
+constexpr auto enum_desc(Meta::Type<ObjectFlags>)
+{
+    return make_array<EnumDesc<ObjectFlags>, 3>({
+        { ObjectFlags::ToBegin, "to_begin" },
+        { ObjectFlags::ToEnd, "to_end" },
+        { ObjectFlags::Inner, "inner" },
+    });
+}
+
 template<WordType word_type>
 Optional<Selection>
 select_word(const Context& context, const Selection& selection,