From 2a0afcc5d0b7ecb47ff90cef2adddc2e48145230 Mon Sep 17 00:00:00 2001
From: Brian Cardarella <bcardarella@gmail.com>
Date: Tue, 23 Jul 2024 19:52:36 -0400
Subject: [PATCH] Add Sourceror.strip_meta/1 (#158)

* Add Sourceror.strip_meta/1

* mix format

---------

Co-authored-by: doorgan <dorgandash@gmail.com>
---
 lib/sourceror.ex        | 13 +++++++++++++
 test/sourceror_test.exs | 18 ++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/lib/sourceror.ex b/lib/sourceror.ex
index 51c1976..7b1aa7b 100644
--- a/lib/sourceror.ex
+++ b/lib/sourceror.ex
@@ -892,6 +892,19 @@ defmodule Sourceror do
     |> Enum.join()
   end
 
+  @doc """
+  A convenience utility function for stripping all meta data out of
+  a quoted expression. This is useful when debugging for readability of very large
+  ASTs.
+  """
+  @spec strip_meta(quoted :: Macro.t()) :: Macro.t()
+  def strip_meta(quoted) do
+    Macro.prewalk(quoted, [], fn
+      {name, _meta, args}, acc -> {{name, {}, args}, acc}
+      other, acc -> {other, acc}
+    end)
+  end
+
   defp do_patch_string(lines, [], seen, _), do: Enum.reverse(lines) ++ seen
 
   defp do_patch_string([], _, seen, _), do: seen
diff --git a/test/sourceror_test.exs b/test/sourceror_test.exs
index c11ff5c..2e53e7d 100644
--- a/test/sourceror_test.exs
+++ b/test/sourceror_test.exs
@@ -1226,4 +1226,22 @@ defmodule SourcerorTest do
              """
     end
   end
+
+  describe "strip_meta/1" do
+    test "will strip all meta data from AST" do
+      original = ~S"""
+      hello world do
+        :ok
+      end
+      """
+
+      quoted = Sourceror.parse_string!(original)
+
+      assert Sourceror.strip_meta(quoted) == {
+               {:hello, {},
+                [{:world, {}, nil}, [{{:__block__, {}, [:do]}, {:__block__, {}, [:ok]}}]]},
+               []
+             }
+    end
+  end
 end