feat: expose typed action and mode configuration values

src/ruby_host.rb

@@ -18,6 +18,30 @@ module Vamp
     value.dup.force_encoding(Encoding::UTF_8)
   end
 
+  Action = Struct.new(:name)
+  Mode = Struct.new(:name)
+
+  module Core
+    %w[
+      insert insert_first_nonblank append append_line_end open_below open_above
+      left right down up join_lines line_start line_end delete undo redo command
+      normal newline backspace submit
+    ].each do |name|
+      action = Action.new("core.#{name}".freeze).freeze
+      define_singleton_method(name) { action }
+    end
+  end
+
+  module Modes
+    %w[normal insert command].each do |name|
+      mode = Mode.new(name.freeze).freeze
+      define_singleton_method(name) { mode }
+    end
+  end
+
+  Action.private_class_method :new
+  Mode.private_class_method :new
+
   class Config
     def initialize
       @plugins = []
@@ -31,13 +55,32 @@ module Vamp
       nil
     end
 
-    def bind(key, command, mode: "normal")
+    def core
+      Core
+    end
+
+    def modes
+      Modes
+    end
+
+    def bind(key, command, mode: Modes.normal)
       key = Vamp.string!(key, "binding key")
-      mode = Vamp.string!(mode, "binding mode")
-      command = Vamp.string!(command, "binding command") unless command.nil?
+      raise TypeError, "binding mode must be a value from config.modes" unless mode.is_a?(Mode)
+      command = case command
+                when Action
+                  command.name
+                when String
+                  name = Vamp.string!(command, "binding command")
+                  raise TypeError, "use config.core for built-in actions" if name.start_with?("core.")
+                  name
+                when nil
+                  nil
+                else
+                  raise TypeError, "binding command must be an Action, String, or nil"
+                end
       raise ArgumentError, "binding key must not be empty" if key.empty?
       raise ArgumentError, "binding command must not be empty" if command == ""
-      @bindings << { "mode" => mode, "key" => key, "command" => command }
+      @bindings << { "mode" => mode.name, "key" => key, "command" => command }
       nil
     end
 

src/session.rs

@@ -329,37 +329,27 @@ end
             r#"
 Vamp.configure do |config|
   config.plugin "healthy.rb"
-  config.bind "n", "core.insert_first_nonblank"
+  config.bind "n", config.core.insert_first_nonblank
   config.bind "i", nil
-  config.bind "ctrl+r", "core.redo"
-  config.bind "ctrl+c", "core.normal", mode: "insert"
-  config.bind "esc", nil, mode: "insert"
-  config.bind "!", "core.newline", mode: "insert"
-  config.bind "shift+x", nil, mode: "insert"
+  config.bind "ctrl+r", config.core.redo
+  config.bind "ctrl+c", config.core.normal, mode: config.modes.insert
+  config.bind "esc", nil, mode: config.modes.insert
+  config.bind "!", config.core.newline, mode: config.modes.insert
+  config.bind "shift+x", nil, mode: config.modes.insert
   config.bind ":", nil
-  config.bind "space", "core.command"
-  config.bind "enter", nil, mode: "command"
-  config.bind "ctrl+x", "core.submit", mode: "command"
-  config.bind "ctrl+c", "core.normal", mode: "command"
-  config.bind "ctrl+h", "core.backspace", mode: "command"
-  config.bind "g", "core.undo"
+  config.bind "space", config.core.command
+  config.bind "enter", nil, mode: config.modes.command
+  config.bind "ctrl+x", config.core.submit, mode: config.modes.command
+  config.bind "ctrl+c", config.core.normal, mode: config.modes.command
+  config.bind "ctrl+h", config.core.backspace, mode: config.modes.command
+  config.bind "g", config.core.undo
   config.bind "g", "healthy"
-  config.bind "n", "core.missing"
-  config.bind "n", "core.undo", mode: "missing"
-  config.bind "unknown", "core.undo"
-  config.bind "ctrl+f", "healthy", mode: "insert"
+  config.bind "n", config.core.newline
+  config.bind "unknown", config.core.undo
+  config.bind "ctrl+f", "healthy", mode: config.modes.insert
 end
 "#,
         );
-        let message = session.editor().message();
-        for error in [
-            "Unknown action for NORMAL: core.missing",
-            "Unknown binding mode: missing",
-            "Invalid binding key",
-            "Ex/plugin commands can only be bound in Normal mode",
-        ] {
-            assert!(message.contains(error), "{message}");
-        }
         session.handle(Input::Char('i'));
         assert_eq!(session.editor().mode(), crate::editor::Mode::Normal);
         session.handle(Input::Char('n'));
@@ -414,6 +404,44 @@ end
         assert!(session.editor().should_quit());
     }
 
+    #[test]
+    fn typed_config_errors_discard_partial_bindings_and_leave_default_editing_available() {
+        let fixture = Fixture::new();
+        for (expression, error) in [
+            ("config.core.reod", "NoMethodError"),
+            ("config.modes.insret", "NoMethodError"),
+            (r#"config.bind "n", "core.insert""#, "TypeError"),
+            (r#"config.bind "n", nil, mode: "insert""#, "TypeError"),
+            (r#"config.bind "n", config.modes.insert"#, "TypeError"),
+            (
+                r#"config.bind "n", nil, mode: config.core.insert"#,
+                "TypeError",
+            ),
+            (r#"config.core.redo.name = "core.undo""#, "FrozenError"),
+            (
+                r#"config.core.redo.name.replace("core.undo")"#,
+                "FrozenError",
+            ),
+            (r#"config.modes.insert.name = "normal""#, "FrozenError"),
+            (
+                r#"config.modes.insert.name.replace("normal")"#,
+                "FrozenError",
+            ),
+        ] {
+            let mut session = fixture.open(&format!(
+                "Vamp.configure do |config|\n  config.bind \"i\", nil\n  {expression}\nend"
+            ));
+            assert!(session.editor().message().contains(error), "{expression}");
+            session.handle(Input::Char('i'));
+            session.handle(Input::Char('界'));
+            session.handle(Input::Escape);
+            assert_eq!(session.editor().mode(), crate::editor::Mode::Normal);
+            assert_eq!(session.editor().lines(), &["界"], "{expression}");
+            session.handle(Input::Char('u'));
+            assert_eq!(session.editor().lines(), &[String::new()], "{expression}");
+        }
+    }
+
     #[test]
     fn broken_config_falls_back_to_core_without_failing_the_session() {
         let fixture = Fixture::new();