I can define and eval BNF definitions

tests/test_sheerka.py

@@ -1,12 +1,10 @@
-import ast
-
 import pytest
 import os
 from os import path
 import shutil
 
 from core.builtin_concepts import BuiltinConcepts, ReturnValueConcept
-from core.concept import Concept, PROPERTIES_TO_SERIALIZE
+from core.concept import Concept, PROPERTIES_TO_SERIALIZE, Property
 from core.sheerka import Sheerka, ExecutionContext
 from evaluators.MutipleSameSuccessEvaluator import MultipleSameSuccessEvaluator
 from parsers.ConceptLexerParser import Sequence, ZeroOrMore, StrMatch, OrderedChoice, Optional, ConceptMatch, \
@@ -63,12 +61,12 @@ def test_builtin_concepts_are_initialized():
 
 
 def test_builtin_concepts_can_be_updated():
-    sheerka = get_sheerka(root_folder, skip_builtins_in_db=False)
+    sheerka = get_sheerka(False, skip_builtins_in_db=False)
     loaded_sheerka = sheerka.get(BuiltinConcepts.SHEERKA)
     loaded_sheerka.metadata.desc = "I have a description"
     sheerka.sdp.modify("Test", sheerka.CONCEPTS_ENTRY, loaded_sheerka.key, loaded_sheerka)
 
-    sheerka = get_sheerka(root_folder)
+    sheerka = get_sheerka(False)
     loaded_sheerka = sheerka.get(BuiltinConcepts.SHEERKA)
 
     assert loaded_sheerka.metadata.desc == "I have a description"
@@ -593,9 +591,8 @@ def test_i_can_create_concept_with_bnf_definition():
 
     saved_definitions = sheerka.sdp.get_safe(sheerka.CONCEPTS_DEFINITIONS_ENTRY)
     expected_bnf = Sequence(
-        ConceptMatch("a"),
-        Optional(Sequence(StrMatch("plus"), ConceptMatch("plus"))),
-        rule_name="plus")
+        ConceptMatch("a", rule_name="a"),
+        Optional(Sequence(StrMatch("plus"), ConceptMatch("plus", rule_name="plus"))))
     assert saved_definitions[saved_concept] == expected_bnf
 
     new_concept = res[0].value.body
@@ -606,7 +603,53 @@ def test_i_can_create_concept_with_bnf_definition():
     assert "plus" in new_concept.props
 
 
-def get_sheerka(root="mem://", skip_builtins_in_db=True):
+def test_i_can_eval_bnf_definitions():
+    sheerka = get_sheerka()
+    concept_a = sheerka.eval("def concept a from bnf 'one' | 'two'")[0].body.body
+
+    res = sheerka.eval("one")
+
+    assert len(res) == 1
+    assert res[0].status
+    assert sheerka.isinstance(res[0].value, concept_a)
+
+
+def test_i_can_eval_bnf_definitions_with_variables():
+    sheerka = get_sheerka()
+    concept_a = sheerka.eval("def concept a from bnf 'one' | 'two'")[0].body.body
+    concept_b = sheerka.eval("def concept b from bnf a 'three'")[0].body.body
+
+    res = sheerka.eval("one three")
+
+    assert len(res) == 1
+    assert res[0].status
+    return_value = res[0].value
+
+    assert sheerka.isinstance(return_value, concept_b)
+    assert return_value.props["a"] == Property("a", concept_a)
+
+
+def test_i_can_eval_bnf_definitions_from_separate_instances():
+    """
+    Same test then before,
+    but make sure that the BNF are correctly persisted and loaded
+    """
+    sheerka = get_sheerka(False)
+    concept_a = sheerka.eval("def concept a from bnf 'one' | 'two'")[0].body.body
+
+    res = get_sheerka(False).eval("one")
+    assert len(res) == 1
+    assert res[0].status
+    assert sheerka.isinstance(res[0].value, concept_a)
+
+    res = get_sheerka(False).eval("two")
+    assert len(res) == 1
+    assert res[0].status
+    assert sheerka.isinstance(res[0].value, concept_a)
+
+
+def get_sheerka(use_dict=True, skip_builtins_in_db=True):
+    root = "mem://" if use_dict else root_folder
     sheerka = Sheerka(skip_builtins_in_db)
     sheerka.initialize(root)