Add a new EvaluatedObject container

This container is used to store values that have already been evaluated.
For instance, 79d5a3a783cf0b5a729e4e467508e955a0cca55f added support
for inferring `tuple()` call arguments, but as a result, the `elts` of a `Tuple`
can be objects not *references*. As a result, `Tuple.elts` can contain class objects
rather than references (names) to class object. The `EvaluatedObject` helps with that,
as we still have to call `.infer()` (albeit a no-op) to grab the inferred value of an element.

1 files changed, 19 insertions, 4 deletions

diff --git a/tests/unittest_inference.py b/tests/unittest_inference.py
index dd833e29..dfae1b8f 100644
--- a/tests/unittest_inference.py
+++ b/tests/unittest_inference.py
@@ -5171,10 +5171,25 @@ def test_builtin_inference_list_of_exceptions():
     inferred = next(node.infer())
     assert isinstance(inferred, nodes.Tuple)
     assert len(inferred.elts) == 2
-    assert isinstance(inferred.elts[0], nodes.ClassDef)
-    assert inferred.elts[0].name == "ValueError"
-    assert isinstance(inferred.elts[1], nodes.ClassDef)
-    assert inferred.elts[1].name == "TypeError"
+    assert isinstance(inferred.elts[0], nodes.EvaluatedObject)
+    assert isinstance(inferred.elts[0].value, nodes.ClassDef)
+    assert inferred.elts[0].value.name == "ValueError"
+    assert isinstance(inferred.elts[1], nodes.EvaluatedObject)
+    assert isinstance(inferred.elts[1].value, nodes.ClassDef)
+    assert inferred.elts[1].value.name == "TypeError"
+
+    # Test that inference of evaluated objects returns what is expected
+    first_elem = next(inferred.elts[0].infer())
+    assert isinstance(first_elem, nodes.ClassDef)
+    assert first_elem.name == "ValueError"
+
+    second_elem = next(inferred.elts[1].infer())
+    assert isinstance(second_elem, nodes.ClassDef)
+    assert second_elem.name == "TypeError"
+
+    # Test that as_string() also works
+    as_string = inferred.as_string()
+    assert as_string.strip() == "(ValueError, TypeError)"
 
 
 @test_utils.require_version(minver="3.6")