Add step and delete commands

lib/irb/cmd/delete.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require_relative "debug"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Delete < Debug
+      def execute(*args)
+        super(pre_cmds: ["delete", *args].join(" "))
+      end
+    end
+  end
+
+  # :startdoc:
+end

lib/irb/cmd/step.rb

@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+require_relative "debug"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Step < Debug
+      def execute(*args)
+        # Run `next` first to move out of binding.irb
+        super(pre_cmds: "next", do_cmds: ["step", *args].join(" "))
+      end
+    end
+  end
+
+  # :startdoc:
+end

lib/irb/extend-command.rb

@@ -126,6 +126,14 @@ def irb_context
       [
         :irb_next, :Next, "cmd/next",
       ],
+      [
+        :irb_delete, :Delete, "cmd/delete",
+        [:delete, NO_OVERRIDE],
+      ],
+      [
+        :irb_step, :Step, "cmd/step",
+        [:step, NO_OVERRIDE],
+      ],
       [
         :irb_continue, :Continue, "cmd/continue",
         [:continue, NO_OVERRIDE],