Refactor to use the AST

Author: NJichev

lib/next_ls/extensions/credo_extension/code_action/remove_debugger.ex

@@ -2,32 +2,103 @@ defmodule NextLS.CredoExtension.CodeAction.RemoveDebugger do
   @moduledoc false
 
   alias GenLSP.Structures.CodeAction
+  alias GenLSP.Structures.Position
   alias GenLSP.Structures.Diagnostic
   alias GenLSP.Structures.Range
   alias GenLSP.Structures.TextEdit
   alias GenLSP.Structures.WorkspaceEdit
+  alias NextLS.ASTHelpers
+  alias NextLS.EditHelpers
+  alias Sourceror.Zipper, as: Z
+  @line_length 121
 
-  def new(diagnostic, _text, uri) do
-    %Diagnostic{range: %Range{start: start}} = diagnostic
-
-    [
-      %CodeAction{
-        title: "Remove debugger",
-        diagnostics: [diagnostic],
-        edit: %WorkspaceEdit{
-          changes: %{
-            uri => [
-              %TextEdit{
-                new_text: "",
-                range: %Range{
-                  start: %{start | character: 0},
-                  end: %{start | character: 0, line: start.line + 1}
+  def new(diagnostic, text, uri) do
+    %Diagnostic{range: range} = diagnostic
+
+    with {:ok, ast, comments} <- parse(text),
+         {:ok, defm} <- ASTHelpers.get_surrounding_module(ast, range.start) do
+      range = make_range(defm)
+      indent = EditHelpers.get_indent(text, range.start.line)
+      diagnostic.range.start
+      ast_without_debugger = remove_debugger(defm, diagnostic.range.start)
+
+      comments =
+        Enum.filter(comments, fn comment ->
+          comment.line > range.start.line && comment.line <= range.end.line
+        end)
+
+      to_algebra_opts = [comments: comments]
+      doc = Code.quoted_to_algebra(ast_without_debugger, to_algebra_opts)
+      formatted = doc |> Inspect.Algebra.format(@line_length) |> IO.iodata_to_binary()
+
+      [
+        %CodeAction{
+          title: "Remove debugger",
+          diagnostics: [diagnostic],
+          edit: %WorkspaceEdit{
+            changes: %{
+              uri => [
+                %TextEdit{
+                  new_text: EditHelpers.add_indent_to_edit(formatted, indent),
+                  range: range
                 }
-              }
-            ]
+              ]
+            }
           }
         }
-      }
-    ]
+      ]
+    else
+      {:error, message} ->
+        %GenLSP.ErrorResponse{code: ErrorCodes.parse_error(), message: inspect(message)}
+    end
+  end
+
+  defp remove_debugger(ast, position) do
+    pos = [line: position.line + 1, column: position.character + 1]
+    result =
+      ast
+      |> Z.zip()
+      |> Z.traverse(fn tree ->
+        node = Z.node(tree)
+        range = Sourceror.get_range(node)
+
+        if matches_debug?(node, pos) &&
+          Sourceror.compare_positions(range.start, pos) in [:lt, :eq] &&
+          Sourceror.compare_positions(range.end, pos) in [:gt, :eq] do
+          Z.remove(tree)
+        else
+          tree
+        end
+      end)
+      |> Z.node()
   end
+
+  defp parse(lines) do
+    lines
+    |> Enum.join("\n")
+    |> Spitfire.parse_with_comments(literal_encoder: &{:ok, {:__block__, &2, [&1]}})
+    |> case do
+      {:error, ast, comments, _errors} ->
+        {:ok, ast, comments}
+
+      other ->
+        other
+    end
+  end
+
+  defp make_range(original_ast) do
+    range = Sourceror.get_range(original_ast)
+
+    %Range{
+      start: %Position{line: range.start[:line] - 1, character: range.start[:column] - 1},
+      end: %Position{line: range.end[:line] - 1, character: range.end[:column] - 1}
+    }
+  end
+
+  defp matches_debug?({:|>, ctx, [_, {{:., ctx, [{:__aliases__, _, [:IO]}, f]}, _, _}]}, pos), do: pos[:line] == ctx[:line]
+  defp matches_debug?({:dbg, ctx, []}, pos), do: pos[:line] == ctx[:line]
+  defp matches_debug?({{:., ctx, [{:__aliases__, _, [:IO]}, f]}, _, _}, pos) when f in [:puts, :inspect], do: pos[:line] == ctx[:line]
+  defp matches_debug?({{:., ctx, [{:__aliases__, _, [:IEx]}, :pry]}, _, _}, pos), do: pos[:line] == ctx[:line]
+  defp matches_debug?({{:., ctx, [{:__aliases__, _, [:Mix]}, :env]}, _, _}, pos), do: pos[:line] == ctx[:line]
+  defp matches_debug?(_, _), do: false
 end

test/next_ls/extensions/credo_extension/remove_debugger_test.exs

@@ -13,19 +13,30 @@ defmodule NextLS.CredoExtension.CodeAction.RemoveDebuggerTest do
       String.split(
         """
         defmodule Test.Debug do
-          def hello() do
-            IO.inspect("foo")
+          def hello(arg) do
+            IO.inspect(arg, label: "DEBUG")
+            arg
           end
         end
         """,
         "\n"
       )
 
-    start = %Position{character: 0, line: 2}
+    expected_edit =
+      String.trim("""
+      defmodule Test.Debug do
+        def hello(arg) do
+          arg
+        end
+      end
+      """)
+
+
+    start = %Position{character: 4, line: 2}
 
     diagnostic = %GenLSP.Structures.Diagnostic{
-      data: %{"namespace" => "credo", "check" => "Elixir.Credo.Check.Warning.Dbg"},
-      message: "you must require Logger before invoking the macro Logger.info/1",
+      data: %{"namespace" => "credo", "check" => "Elixir.Credo.Check.Warning.IoInspect"},
+      message: "There should be no calls to `IO.inspect/2`",
       source: "Elixir",
       range: %GenLSP.Structures.Range{
         start: start,
@@ -44,8 +55,8 @@ defmodule NextLS.CredoExtension.CodeAction.RemoveDebuggerTest do
              changes: %{
                ^uri => [
                  %TextEdit{
-                   new_text: "",
-                   range: %Range{start: ^start, end: %{line: 3, character: 0}}
+                   new_text: expected_edit,
+                   range: %Range{start: %{line: 0, character: 0}, end: %{line: 5, character: 3}}
                  }
                ]
              }
@@ -66,14 +77,24 @@ defmodule NextLS.CredoExtension.CodeAction.RemoveDebuggerTest do
         String.split(
           """
           defmodule Test.Debug do
-            def hello() do
+            def hello(arg) do
               #{code}
+              arg
             end
           end
           """,
           "\n"
         )
 
+      expected_edit =
+        String.trim("""
+        defmodule Test.Debug do
+          def hello(arg) do
+            arg
+          end
+        end
+        """)
+
       start = %Position{character: 4, line: 2}
 
       diagnostic = %GenLSP.Structures.Diagnostic{
@@ -97,12 +118,125 @@ defmodule NextLS.CredoExtension.CodeAction.RemoveDebuggerTest do
                changes: %{
                  ^uri => [
                    %TextEdit{
-                     new_text: "",
-                     range: %Range{start: %{line: 2, character: 0}, end: %{line: 3, character: 0}}
+                     new_text: ^expected_edit,
+                     range: %Range{start: %{line: 0, character: 0}, end: %{line: 5, character: 3}}
                    }
                  ]
                }
              } = code_action.edit
     end
   end
+
+  test "works on multiple expressions on one line" do
+    text =
+      String.split(
+        """
+        defmodule Test.Debug do
+          def hello(arg) do
+            IO.inspect(arg, label: "DEBUG"); arg
+          end
+        end
+        """,
+        "\n"
+      )
+
+    expected_edit =
+      String.trim("""
+      defmodule Test.Debug do
+        def hello(arg) do
+          arg
+        end
+      end
+      """)
+
+
+    start = %Position{character: 4, line: 2}
+
+    diagnostic = %GenLSP.Structures.Diagnostic{
+      data: %{"namespace" => "credo", "check" => "Elixir.Credo.Check.Warning.IoInspect"},
+      message: "There should be no calls to `IO.inspect/2`",
+      source: "Elixir",
+      range: %GenLSP.Structures.Range{
+        start: start,
+        end: %{start | character: 999}
+      }
+    }
+
+    uri = "file:///home/owner/my_project/hello.ex"
+
+    assert [code_action] = RemoveDebugger.new(diagnostic, text, uri)
+    assert is_struct(code_action, CodeAction)
+    assert [diagnostic] == code_action.diagnostics
+    assert code_action.title == "Remove debugger"
+
+    assert %WorkspaceEdit{
+             changes: %{
+               ^uri => [
+                 %TextEdit{
+                   new_text: ^expected_edit,
+                   range: %Range{start: %{line: 0, character: 0}, end: %{line: 5, character: 3}}
+                 }
+               ]
+             }
+           } = code_action.edit
+  end
+
+  test "handles pipe calls" do
+    text =
+      String.split(
+        """
+        defmodule Test.Debug do
+          def hello(arg) do
+            arg
+            |> Enum.map(& &1 * &1)
+            |> IO.inspect(label: "FOO")
+            |> Enum.sum()
+          end
+        end
+        """,
+        "\n"
+      )
+
+    expected_edit =
+      String.trim("""
+      defmodule Test.Debug do
+        def hello(arg) do
+          arg
+          |> Enum.map(& &1 * &1)
+          |> Enum.sum()
+        end
+      end
+      """)
+
+
+    start = %Position{character: 10, line: 4}
+
+    diagnostic = %GenLSP.Structures.Diagnostic{
+      data: %{"namespace" => "credo", "check" => "Elixir.Credo.Check.Warning.IoInspect"},
+      message: "There should be no calls to `IO.inspect/2`",
+      source: "Elixir",
+      range: %GenLSP.Structures.Range{
+        start: start,
+        end: %{start | character: 999}
+      }
+    }
+
+    uri = "file:///home/owner/my_project/hello.ex"
+
+    assert [code_action] = RemoveDebugger.new(diagnostic, text, uri)
+    assert is_struct(code_action, CodeAction)
+    assert [diagnostic] == code_action.diagnostics
+    assert code_action.title == "Remove debugger"
+
+    assert %WorkspaceEdit{
+             changes: %{
+               ^uri => [
+                 %TextEdit{
+                   new_text: ^expected_edit,
+                   range: %Range{start: %{line: 0, character: 0}, end: %{line: 5, character: 3}}
+                 }
+               ]
+             }
+           } = code_action.edit
+  end
 end