control_d_handler: don't mutate eval_string within the handlercontrol-d-ruby-3-friendly

This is a preparational step for #1824
(Enabling `# frozen_string_literal: true` in `~/.pryc` crashes most operations)

Alternative to https://github.com/pry/pry/pull/2030
(config: delete the `control_d_handler` option)

We had to jump a few hoops to change how the handler works. The problem is that
mutation is the default expected behaviour. Therefore, we had to change its
API. There's no need to pass `eval_string` because `pry_instance` already has it
as an attribute.

`config.control_d_handler` is a proxy proc, to preserve backwards compatibility
with users of old signature (one known user is Pry Byebug). The handler will
emit a warning if the old signature is used.

1 files changed, 27 insertions, 0 deletions

diff --git a/lib/pry/config.rb b/lib/pry/config.rb
index 55718200..2ed3542a 100644
--- a/lib/pry/config.rb
+++ b/lib/pry/config.rb
@@ -261,6 +261,33 @@ class Pry
       @custom_attrs = @custom_attrs.dup
     end
 
+    def control_d_handler=(value)
+      proxy_proc =
+        if value.arity == 2
+          Pry::Warning.warn(
+            "control_d_handler's arity of 2 parameters was deprecated. Now it " \
+            'gets passed just 1 parameter (pry_instance). Please update your ' \
+            'handler'
+          )
+          proc do |*args|
+            if args.size == 2
+              value.call(args.first, args[1])
+            else
+              value.call(args.first.eval_string, args.first)
+            end
+          end
+        else
+          proc do |*args|
+            if args.size == 2
+              value.call(args[1])
+            else
+              value.call(args.first)
+            end
+          end
+        end
+      @control_d_handler = proxy_proc
+    end
+
     private
 
     def lazy_readline