From 1037edf659b401be872034285318cf7fd0fe9508 Mon Sep 17 00:00:00 2001
From: Lukasz Samson <lukaszsamson@gmail.com>
Date: Mon, 3 Feb 2020 19:34:49 +0100
Subject: [PATCH] fix invalid vars suggestions in guards

---
 lib/elixir_sense/core/metadata_builder.ex     |  9 +++-
 .../core/metadata_builder_test.exs            | 49 ++++++++++++++++++-
 test/elixir_sense/suggestions_test.exs        | 16 ++++++
 3 files changed, 71 insertions(+), 3 deletions(-)

diff --git a/lib/elixir_sense/core/metadata_builder.ex b/lib/elixir_sense/core/metadata_builder.ex
index b1310ada..7238200e 100644
--- a/lib/elixir_sense/core/metadata_builder.ex
+++ b/lib/elixir_sense/core/metadata_builder.ex
@@ -237,7 +237,7 @@ defmodule ElixirSense.Core.MetadataBuilder do
     |> result(ast)
   end
 
-  defp pre_clause({_, [line: line, column: _column], _} = ast, state, lhs) do
+  defp pre_clause({_clause, [line: line, column: _column], _} = ast, state, lhs) do
     state
     |> new_alias_scope
     |> new_import_scope
@@ -408,7 +408,7 @@ defmodule ElixirSense.Core.MetadataBuilder do
           ]},
          state
        )
-       when def_name in [:defguard, :defguardp] do
+       when def_name in @defs do
     ast_without_params = {def_name, meta, [{name, add_no_call(meta2), []}, body]}
     pre_func(ast_without_params, state, %{line: line, col: column}, name, params)
   end
@@ -1017,6 +1017,11 @@ defmodule ElixirSense.Core.MetadataBuilder do
     {ast, [var_info | vars]}
   end
 
+  # drop right side of guard expression as guards cannot define vars
+  defp match_var({:when, _, [left, _right]}, vars) do
+    match_var(left, vars)
+  end
+
   defp match_var(ast, vars) do
     {ast, vars}
   end
diff --git a/test/elixir_sense/core/metadata_builder_test.exs b/test/elixir_sense/core/metadata_builder_test.exs
index 3093bd90..783b175f 100644
--- a/test/elixir_sense/core/metadata_builder_test.exs
+++ b/test/elixir_sense/core/metadata_builder_test.exs
@@ -121,7 +121,7 @@ defmodule ElixirSense.Core.MetadataBuilderTest do
       """
       defmodule MyModule do
         var_out1 = 1
-        def func(%{key1: par1, key2: [par2|[par3, _]]}, par4) do
+        def func(%{key1: par1, key2: [par2|[par3, _]]}, par4, _par5) do
           var_in1 = 1
           var_in2 = 1
           IO.puts ""
@@ -150,6 +150,53 @@ defmodule ElixirSense.Core.MetadataBuilderTest do
            ]
   end
 
+  test "guards do not define vars" do
+    state =
+      """
+      defmodule MyModule do
+        def func1(a) when is_integer(b) do
+          IO.puts("")
+        end
+        def func2(a) when is_integer(b) or is_list(c) do
+          IO.puts("")
+        end
+        def func3(a) when is_integer(b) when is_list(c) do
+          IO.puts("")
+        end
+
+        case x do
+          y when is_integer(z) ->
+            IO.puts("")
+        end
+
+        with x when is_integer(y) <- z do
+          IO.puts("")
+        end
+
+        def func3(a) when is_integer(b)
+      end
+      """
+      |> string_to_state
+
+    vars = state |> get_line_vars(3)
+    assert vars == [%VarInfo{is_definition: false, name: :a, positions: [{2, 13}], scope_id: 2}]
+
+    vars = state |> get_line_vars(6)
+    assert vars == [%VarInfo{is_definition: false, name: :a, positions: [{5, 13}], scope_id: 2}]
+
+    vars = state |> get_line_vars(9)
+    assert vars == [%VarInfo{is_definition: false, name: :a, positions: [{8, 13}], scope_id: 2}]
+
+    vars = state |> get_line_vars(14)
+    assert vars == [%VarInfo{is_definition: false, name: :y, positions: [{13, 5}], scope_id: 7}]
+
+    vars = state |> get_line_vars(18)
+    assert vars == [%VarInfo{is_definition: false, name: :x, positions: [{17, 8}], scope_id: 2}]
+
+    vars = state |> get_line_vars(21)
+    assert vars == [%VarInfo{is_definition: false, name: :a, positions: [{21, 13}], scope_id: 2}]
+  end
+
   test "rebinding vars" do
     state =
       """
diff --git a/test/elixir_sense/suggestions_test.exs b/test/elixir_sense/suggestions_test.exs
index 493995ad..467d7215 100644
--- a/test/elixir_sense/suggestions_test.exs
+++ b/test/elixir_sense/suggestions_test.exs
@@ -843,6 +843,22 @@ defmodule ElixirSense.SuggestionsTest do
            ]
   end
 
+  test "only list defined params in guard" do
+    buffer = """
+    defmodule MyServer do
+      def new(my_var) when is_integer(my
+    end
+    """
+
+    list =
+      ElixirSense.suggestions(buffer, 2, 37)
+      |> Enum.filter(fn s -> s.type == :variable end)
+
+    # TODO hint my_var instead of my
+
+    assert list == [%{name: "my_var", type: :variable}]
+  end
+
   test "lists attributes" do
     buffer = """
     defmodule MyModule do