feat(commands): from-pipe (#378)

Co-authored-by: Nikola Jichev <[email protected]>

lib/next_ls.ex

@@ -142,7 +142,8 @@ defmodule NextLS do
          document_formatting_provider: true,
          execute_command_provider: %GenLSP.Structures.ExecuteCommandOptions{
            commands: [
-             "to-pipe"
+             "to-pipe",
+             "from-pipe"
            ]
          },
          hover_provider: true,
@@ -618,14 +619,27 @@ defmodule NextLS do
       ) do
     reply =
       case command do
+        "from-pipe" ->
+          [arguments] = params.arguments
+
+          uri = arguments["uri"]
+          position = arguments["position"]
+          text = lsp.assigns.documents[uri]
+
+          NextLS.Commands.Pipe.from(%{
+            uri: uri,
+            text: text,
+            position: position
+          })
+
         "to-pipe" ->
           [arguments] = params.arguments
 
           uri = arguments["uri"]
           position = arguments["position"]
           text = lsp.assigns.documents[uri]
 
-          NextLS.Commands.ToPipe.run(%{
+          NextLS.Commands.Pipe.to(%{
             uri: uri,
             text: text,
             position: position

lib/next_ls/commands/to_pipe.ex → lib/next_ls/commands/pipe.ex

@@ -1,4 +1,4 @@
-defmodule NextLS.Commands.ToPipe do
+defmodule NextLS.Commands.Pipe do
   @moduledoc false
   import Schematic
 
@@ -18,7 +18,7 @@ defmodule NextLS.Commands.ToPipe do
     })
   end
 
-  def run(opts) do
+  def to(opts) do
     with {:ok, %{text: text, uri: uri, position: position}} <- unify(opts(), Map.new(opts)),
          {:ok, ast} = parse(text),
          {:ok, {t, m, [argument | rest]} = original} <- get_node(ast, position) do
@@ -46,6 +46,34 @@ defmodule NextLS.Commands.ToPipe do
     end
   end
 
+  def from(opts) do
+    with {:ok, %{text: text, uri: uri, position: position}} <- unify(opts(), Map.new(opts)),
+         {:ok, ast} = parse(text),
+         {:ok, {:|>, _m, [left, {right, _, args}]} = original} <- get_pipe_node(ast, position) do
+      range = make_range(original)
+      indent = EditHelpers.get_indent(text, range.start.line)
+      unpiped = {right, [], [left | args]}
+
+      %WorkspaceEdit{
+        changes: %{
+          uri => [
+            %TextEdit{
+              new_text:
+                EditHelpers.add_indent_to_edit(
+                  Macro.to_string(unpiped),
+                  indent
+                ),
+              range: range
+            }
+          ]
+        }
+      }
+    else
+      {:error, message} ->
+        %GenLSP.ErrorResponse{code: ErrorCodes.parse_error(), message: inspect(message)}
+    end
+  end
+
   defp parse(lines) do
     lines
     |> Enum.join("\n")
@@ -109,4 +137,35 @@ defmodule NextLS.Commands.ToPipe do
         {:ok, node}
     end
   end
+
+  def get_pipe_node(ast, pos) do
+    pos = [line: pos.line + 1, column: pos.character + 1]
+
+    result =
+      ast
+      |> Z.zip()
+      |> Z.traverse(nil, fn tree, acc ->
+        node = Z.node(tree)
+        range = Sourceror.get_range(node)
+
+        if not is_nil(range) and match?({:|>, _, _}, node) do
+          if Sourceror.compare_positions(range.start, pos) == :lt &&
+               Sourceror.compare_positions(range.end, pos) == :gt do
+            {tree, node}
+          else
+            {tree, acc}
+          end
+        else
+          {tree, acc}
+        end
+      end)
+
+    case result do
+      {_, nil} ->
+        {:error, "could not find a pipe operator at the cursor position"}
+
+      {_, {_t, _m, [_argument | _rest]} = node} ->
+        {:ok, node}
+    end
+  end
 end

lib/next_ls/document_symbol.ex

@@ -33,9 +33,7 @@ defmodule NextLS.DocumentSymbol do
           ast
       end
 
-    ast
-    |> walker(nil)
-    |> List.wrap()
+    List.wrap(walker(ast, nil))
   end
 
   defp walker([{{:__literal__, _, [:do]}, {_, _, _exprs} = ast}], mod) do

lib/next_ls/runtime/sidecar.ex

@@ -17,6 +17,7 @@ defmodule NextLS.Runtime.Sidecar do
   end
 
   def handle_info({:tracer, :dbg, term}, state) do
+    # credo:disable-for-next-line
     dbg(term)
 
     {:noreply, state}
@@ -82,6 +83,7 @@ defmodule NextLS.Runtime.Sidecar do
   end
 
   def handle_info({{:tracer, :dbg}, payload}, state) do
+    # credo:disable-for-next-line
     dbg(payload)
     {:noreply, state}
   end