Simplify markdown rendering of debugger exceptions

One of the most common use cases of the markdown
version is to feed it to LLMs and both code and
headers make it too verbose.

Author: josevalim

lib/plug/templates/debugger.md.eex

@@ -4,24 +4,6 @@ Exception:
 
     <%= String.replace(@formatted, "\n", "\n    ") %>
 
-Code:
-<%= for frame <- @frames do %>
-`<%= h frame.file %>`
-<%= if (snippet = frame.snippet) && snippet != [] do %>
-    <%= for {index, line, highlight} <- snippet do %><%= if highlight do %><%= h index %>>  <% else %><%= h index %>   <% end %><%= h String.trim_trailing(line) %>
-    <% end %><% else %>
-    No code available.
-<% end %><%= if frame.args do %>
-  Called with <%= length(frame.args) %> arguments
-
-  <%= for arg <- frame.args do %>* `<%= h inspect arg %>`
-  <% end %><% end %><%= if frame.clauses do %><% {min, max, clauses} = frame.clauses %>
-  Attempted function clauses (showing <%= min %> out of <%= max %>)
-
-    <%= for clause <- clauses do %> <%= clause %>
-    <% end %>
-<% end %><% end %>
-
 ## Connection details
 
 ### Params
@@ -33,10 +15,6 @@ Code:
   * URI: <%= url(@conn) %>
   * Query string: <%= @conn.query_string %>
 
-### Headers
-  <%= for {key, value} <- Enum.sort(@conn.req_headers) do %>
-  * <%= key %>: <%= value %><% end %>
-
 ### Session
 
     <%= inspect(@session) %>

test/plug/debugger_test.exs

@@ -402,22 +402,6 @@ defmodule Plug.DebuggerTest do
     assert conn.resp_body =~ "unsupported media type foo/bar"
   end
 
-  test "renders bad match attempted arguments" do
-    conn =
-      conn(:get, "/bad_match")
-      |> put_req_header("accept", "text/markdown")
-      |> put_resp_header("content-security-policy", "abcdef")
-
-    capture_log(fn -> assert_raise(FunctionClauseError, fn -> Router.call(conn, []) end) end)
-    {_status, _headers, body} = sent_resp(conn)
-
-    assert body =~ "# FunctionClauseError at GET /bad_match"
-    assert body =~ "Code:\n"
-    assert body =~ "  Called with 2 arguments"
-    assert body =~ "  * `:six`"
-    assert body =~ "  * `:one`"
-  end
-
   test "render actions when an implementation of `Plug.Exception` has it" do
     [%{label: action_label}] = Plug.Exception.actions(%ActionableError{})