Let's think of some hypothetical (close to practical) scenario example. Let's say I need a retrieval of fully-qualified name for a function at point.
In Emacs, I can start prototyping advising function in a scratch buffer changing the behavior of lsp--symbol-information (or related) function. I can try it out right there. I can easily debug, profile, enable and disable this feature without ever having to restart Emacs. Hell, I wouldn't even have to save it — it's all dynamic, all in-place, it's like playing a videogame.
In Neovim, I'd have to create/modify a Lua file. Find the right LSP handler to override. Write the override function. Reload the editor (losing my state), or source the file. There's no easy way to temporarily test without affecting my config. Sure, one can use Fennel for replicating REPL-driven development, but that still be limited compared to Emacs — no advice system; can't easily revert (no advice-remove like stuff); limited introspection; scope issues — need to manage original function references manually; harder discovery — no describe-function like stuff.
In VSCode to get something like that you'd need to create an entire extension project; write typescript/javascript; compile the extension; install it in VSCode; sometime reload VSCode; debug through the extension host; there's no "just try something" way.
Joyride is a game-changer for VSCode — one can use Clojure-based scripting directly, making it almost Emacs-like, yet still — no advising, can't change editor's core internals — they are not exposed to you, there's no true runtime modification of core behaviors.
So no, VSCode and Neovim do not meet the OP's criteria.
Let's think of some hypothetical (close to practical) scenario example. Let's say I need a retrieval of fully-qualified name for a function at point.
In Emacs, I can start prototyping advising function in a scratch buffer changing the behavior of lsp--symbol-information (or related) function. I can try it out right there. I can easily debug, profile, enable and disable this feature without ever having to restart Emacs. Hell, I wouldn't even have to save it — it's all dynamic, all in-place, it's like playing a videogame.
In Neovim, I'd have to create/modify a Lua file. Find the right LSP handler to override. Write the override function. Reload the editor (losing my state), or source the file. There's no easy way to temporarily test without affecting my config. Sure, one can use Fennel for replicating REPL-driven development, but that still be limited compared to Emacs — no advice system; can't easily revert (no advice-remove like stuff); limited introspection; scope issues — need to manage original function references manually; harder discovery — no describe-function like stuff.
In VSCode to get something like that you'd need to create an entire extension project; write typescript/javascript; compile the extension; install it in VSCode; sometime reload VSCode; debug through the extension host; there's no "just try something" way.
Joyride is a game-changer for VSCode — one can use Clojure-based scripting directly, making it almost Emacs-like, yet still — no advising, can't change editor's core internals — they are not exposed to you, there's no true runtime modification of core behaviors.
So no, VSCode and Neovim do not meet the OP's criteria.