feat(definition): local function (#78)

Author: mhanberg

Diff for: .github/workflows/ci.yaml

@@ -43,6 +43,9 @@ jobs:
           MIX_ENV: test
         run: mix compile
 
+      - name: remove tmp dir
+        run: rm -rf tmp
+
       - name: Run Tests
         run: mix test
 

Diff for: lib/next_ls.ex

@@ -21,6 +21,7 @@ defmodule NextLS do
     Initialize,
     Shutdown,
     TextDocumentDocumentSymbol,
+    TextDocumentDefinition,
     TextDocumentFormatting,
     WorkspaceSymbol
   }
@@ -45,6 +46,7 @@ defmodule NextLS do
   alias NextLS.DiagnosticCache
   alias NextLS.Runtime
   alias NextLS.SymbolTable
+  alias NextLS.Definition
 
   def start_link(args) do
     {args, opts} =
@@ -97,12 +99,43 @@ defmodule NextLS do
          },
          document_formatting_provider: true,
          workspace_symbol_provider: true,
-         document_symbol_provider: true
+         document_symbol_provider: true,
+         definition_provider: true
        },
        server_info: %{name: "NextLS"}
      }, assign(lsp, root_uri: root_uri)}
   end
 
+  def handle_request(%TextDocumentDefinition{params: %{text_document: %{uri: uri}, position: position}}, lsp) do
+    result =
+      case Definition.fetch(
+             URI.parse(uri).path,
+             {position.line + 1, position.character + 1},
+             :symbol_table,
+             :reference_table
+           ) do
+        nil ->
+          nil
+
+        [{file, line, column} | _] ->
+          %Location{
+            uri: "file://#{file}",
+            range: %Range{
+              start: %Position{
+                line: line - 1,
+                character: column - 1
+              },
+              end: %Position{
+                line: line - 1,
+                character: column - 1
+              }
+            }
+          }
+      end
+
+    {:reply, result, lsp}
+  end
+
   def handle_request(%TextDocumentDocumentSymbol{params: %{text_document: %{uri: uri}}}, lsp) do
     symbols =
       try do
@@ -343,6 +376,12 @@ defmodule NextLS do
     {:noreply, lsp}
   end
 
+  def handle_info({{:tracer, :local_function}, payload}, lsp) do
+    SymbolTable.put_reference(lsp.assigns.symbol_table, payload)
+    GenLSP.log(lsp, "[NextLS] Updated the reference table!")
+    {:noreply, lsp}
+  end
+
   def handle_info(:publish, lsp) do
     GenLSP.log(lsp, "[NextLS] Compiled!")
 

Diff for: lib/next_ls/definition.ex

@@ -0,0 +1,32 @@
+defmodule NextLS.Definition do
+  def fetch(file, {line, col}, dets_symbol_table, dets_ref_table) do
+    ref =
+      :dets.select(
+        dets_ref_table,
+        [
+          {{{:"$1", {{:"$2", :"$3"}, {:"$4", :"$5"}}}, :"$6"},
+           [
+             {:andalso,
+              {:andalso, {:andalso, {:andalso, {:==, :"$1", file}, {:"=<", :"$2", line}}, {:"=<", :"$3", col}},
+               {:"=<", line, :"$4"}}, {:"=<", col, :"$5"}}
+           ], [:"$6"]}
+        ]
+      )
+
+    :dets.traverse(dets_symbol_table, fn x -> {:continue, x} end)
+
+    case ref do
+      [ref] ->
+        :dets.select(
+          dets_symbol_table,
+          [
+            {{:_, %{line: :"$3", name: :"$2", module: :"$1", col: :"$4", file: :"$5"}},
+             [{:andalso, {:==, :"$1", ref.module}, {:==, :"$2", ref.func}}], [{{:"$5", :"$3", :"$4"}}]}
+          ]
+        )
+
+      _ ->
+        nil
+    end
+  end
+end

Diff for: lib/next_ls/symbol_table.ex

@@ -22,6 +22,9 @@ defmodule NextLS.SymbolTable do
   @spec put_symbols(pid() | atom(), list(tuple())) :: :ok
   def put_symbols(server, symbols), do: GenServer.cast(server, {:put_symbols, symbols})
 
+  @spec put_reference(pid() | atom(), map()) :: :ok
+  def put_reference(server, reference), do: GenServer.cast(server, {:put_reference, reference})
+
   @spec symbols(pid() | atom()) :: list(struct())
   def symbols(server), do: GenServer.call(server, :symbols)
 
@@ -42,7 +45,13 @@ defmodule NextLS.SymbolTable do
         type: :duplicate_bag
       )
 
-    {:ok, %{table: name}}
+    {:ok, ref_name} =
+      :dets.open_file(:reference_table,
+        file: Path.join(path, "reference_table.dets") |> String.to_charlist(),
+        type: :duplicate_bag
+      )
+
+    {:ok, %{table: name, reference_table: ref_name}}
   end
 
   def handle_call({:symbols, file}, _, state) do
@@ -74,10 +83,30 @@ defmodule NextLS.SymbolTable do
 
   def handle_call(:close, _, state) do
     :dets.close(state.table)
+    :dets.close(state.reference_table)
 
     {:reply, :ok, state}
   end
 
+  def handle_cast({:put_reference, reference}, state) do
+    %{
+      meta: meta,
+      func: func,
+      arity: _arity,
+      file: file,
+      module: _module
+    } = reference
+
+    range = {{meta[:line], meta[:column]}, {meta[:line], meta[:column] + String.length(to_string(func))}}
+
+    :dets.insert(state.reference_table, {
+      {file, range},
+      reference
+    })
+
+    {:noreply, state}
+  end
+
   def handle_cast({:put_symbols, symbols}, state) do
     %{
       module: mod,
@@ -120,6 +149,9 @@ defmodule NextLS.SymbolTable do
     end
 
     for {name, {:v1, type, _meta, clauses}} <- defs, {meta, _, _, _} <- clauses do
+      _ = foo()
+      _ = foo()
+
       :dets.insert(
         state.table,
         {mod,
@@ -136,4 +168,6 @@ defmodule NextLS.SymbolTable do
 
     {:noreply, state}
   end
+
+  def foo(), do: :ok
 end

Diff for: priv/monkey/_next_ls_private_compiler.ex

@@ -1,4 +1,33 @@
 defmodule NextLSPrivate.Tracer do
+  def trace(:start, env) do
+    :ok
+  end
+
+  def trace({:local_function, meta, func, arity}, env) do
+    parent = "NEXTLS_PARENT_PID" |> System.get_env() |> Base.decode64!() |> :erlang.binary_to_term()
+
+    module =
+      case Macro.Env.lookup_import(env, {func, arity}) do
+        [{_, module}] -> module
+        [] -> env.module
+      end
+
+    Process.send(
+      parent,
+      {{:tracer, :local_function},
+       %{
+         meta: meta,
+         func: func,
+         arity: arity,
+         file: env.file,
+         module: module
+       }},
+      []
+    )
+
+    :ok
+  end
+
   def trace({:on_module, bytecode, _}, env) do
     parent = "NEXTLS_PARENT_PID" |> System.get_env() |> Base.decode64!() |> :erlang.binary_to_term()
 
@@ -15,7 +44,14 @@ defmodule NextLSPrivate.Tracer do
 
     Process.send(
       parent,
-      {:tracer, %{file: env.file, module: env.module, module_line: line, struct: struct, defs: defs}},
+      {:tracer,
+       %{
+         file: env.file,
+         module: env.module,
+         module_line: line,
+         struct: struct,
+         defs: defs
+       }},
       []
     )
 

Diff for: test/next_ls/symbol_table_test.exs

@@ -5,6 +5,7 @@ defmodule NextLS.SymbolTableTest do
   alias NextLS.SymbolTable
 
   setup %{tmp_dir: dir} do
+    File.mkdir_p!(dir)
     pid = start_supervised!({SymbolTable, [path: dir]})
 
     Process.link(pid)