Move and enhance python API grammar tests (#6538)

The existing test for python API grammar is moved to the right location, `yapf`ed, and changed according to the new style of python API tests. Additionally, minor changes are introduced in order to be an exact translation of https://github.com/cvc5/cvc5/blob/master/test/unit/api/grammar_black.cpp

1 files changed, 137 insertions, 0 deletions

diff --git a/test/python/unit/api/test_grammar.py b/test/python/unit/api/test_grammar.py
new file mode 100644
index 000000000..db567a6ba
--- /dev/null
+++ b/test/python/unit/api/test_grammar.py
@@ -0,0 +1,137 @@
+###############################################################################
+# Top contributors (to current version):
+#   Yoni Zohar, Makai Mann, Mudathir Mohamed
+#
+# This file is part of the cvc5 project.
+#
+# Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
+# in the top-level source directory and their institutional affiliations.
+# All rights reserved.  See the file COPYING in the top-level source
+# directory for licensing information.
+# #############################################################################
+#
+# Translated from test/unit/api/grammar_black.h
+##
+
+import pytest
+
+import pycvc5
+from pycvc5 import kinds, Term
+
+
+@pytest.fixture
+def solver():
+    return pycvc5.Solver()
+
+
+def test_add_rule(solver):
+    boolean = solver.getBooleanSort()
+    integer = solver.getIntegerSort()
+
+    null_term = Term(solver)
+    start = solver.mkVar(boolean)
+    nts = solver.mkVar(boolean)
+
+    # expecting no error
+    g = solver.mkSygusGrammar([], [start])
+
+    g.addRule(start, solver.mkBoolean(False))
+
+    # expecting errors
+    with pytest.raises(RuntimeError):
+        g.addRule(null_term, solver.mkBoolean(False))
+    with pytest.raises(RuntimeError):
+        g.addRule(start, null_term)
+    with pytest.raises(RuntimeError):
+        g.addRule(nts, solver.mkBoolean(False))
+    with pytest.raises(RuntimeError):
+        g.addRule(start, solver.mkInteger(0))
+    with pytest.raises(RuntimeError):
+        g.addRule(start, nts)
+
+    # expecting no errors
+    solver.synthFun("f", {}, boolean, g)
+
+    # expecting an error
+    with pytest.raises(RuntimeError):
+        g.addRule(start, solver.mkBoolean(False))
+
+
+def test_add_rules(solver):
+    boolean = solver.getBooleanSort()
+    integer = solver.getIntegerSort()
+
+    null_term = Term(solver)
+    start = solver.mkVar(boolean)
+    nts = solver.mkVar(boolean)
+
+    g = solver.mkSygusGrammar([], [start])
+
+    g.addRules(start, {solver.mkBoolean(False)})
+
+    #Expecting errors
+    with pytest.raises(RuntimeError):
+        g.addRules(null_term, [solver.mkBoolean(False)])
+    with pytest.raises(RuntimeError):
+        g.addRules(start, [null_term])
+    with pytest.raises(RuntimeError):
+        g.addRules(nts, [solver.mkBoolean(False)])
+    with pytest.raises(RuntimeError):
+        g.addRules(start, [solver.mkInteger(0)])
+    with pytest.raises(RuntimeError):
+        g.addRules(start, [nts])
+    #Expecting no errors
+    solver.synthFun("f", {}, boolean, g)
+
+    #Expecting an error
+    with pytest.raises(RuntimeError):
+        g.addRules(start, solver.mkBoolean(False))
+
+
+def test_add_any_constant(solver):
+    boolean = solver.getBooleanSort()
+
+    null_term = Term(solver)
+    start = solver.mkVar(boolean)
+    nts = solver.mkVar(boolean)
+
+    g = solver.mkSygusGrammar({}, {start})
+
+    g.addAnyConstant(start)
+    g.addAnyConstant(start)
+
+    with pytest.raises(RuntimeError):
+        g.addAnyConstant(null_term)
+    with pytest.raises(RuntimeError):
+        g.addAnyConstant(nts)
+
+    solver.synthFun("f", {}, boolean, g)
+
+    with pytest.raises(RuntimeError):
+        g.addAnyConstant(start)
+
+
+def test_add_any_variable(solver):
+    boolean = solver.getBooleanSort()
+
+    null_term = Term(solver)
+    x = solver.mkVar(boolean)
+    start = solver.mkVar(boolean)
+    nts = solver.mkVar(boolean)
+
+    g1 = solver.mkSygusGrammar({x}, {start})
+    g2 = solver.mkSygusGrammar({}, {start})
+
+    g1.addAnyVariable(start)
+    g1.addAnyVariable(start)
+    g2.addAnyVariable(start)
+
+    with pytest.raises(RuntimeError):
+        g1.addAnyVariable(null_term)
+    with pytest.raises(RuntimeError):
+        g1.addAnyVariable(nts)
+
+    solver.synthFun("f", {}, boolean, g1)
+
+    with pytest.raises(RuntimeError):
+        g1.addAnyVariable(start)