From 1cb6af74d71309241374867435024efb8c63779c Mon Sep 17 00:00:00 2001
From: Evgeny Skvortsov <71790359+EvgSkv@users.noreply.github.com>
Date: Wed, 15 Jan 2025 19:37:32 -0800
Subject: [PATCH] Make propositional implication to always be available.

---
 .../propositional_implication_test.l          | 34 +++++++++++++++++++
 .../propositional_implication_test.txt        |  6 ++++
 integration_tests/run_tests.py                |  2 ++
 parser_py/parse.py                            |  6 ++--
 4 files changed, 45 insertions(+), 3 deletions(-)
 create mode 100644 integration_tests/propositional_implication_test.l
 create mode 100644 integration_tests/propositional_implication_test.txt

diff --git a/integration_tests/propositional_implication_test.l b/integration_tests/propositional_implication_test.l
new file mode 100644
index 0000000..2998f9d
--- /dev/null
+++ b/integration_tests/propositional_implication_test.l
@@ -0,0 +1,34 @@
+#
+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Testing propositional implication.
+
+Bird("duck");
+Bird("sparrow");
+
+Animal("dog");
+
+Dragon("wyvern");
+
+Flies("duck");
+Flies("sparrow");
+Flies("wyvern");
+
+WhoFiles("animal") :- Animal(x) => Flies(x);
+WhoFiles("bird") :- Bird(x) => Flies(x);
+WhoFiles("dragon") :- Dragon(x) => Flies(x);
+
+@OrderBy(Test, "col0");
+Test(x) :- WhoFiles(x);
diff --git a/integration_tests/propositional_implication_test.txt b/integration_tests/propositional_implication_test.txt
new file mode 100644
index 0000000..bb0c904
--- /dev/null
+++ b/integration_tests/propositional_implication_test.txt
@@ -0,0 +1,6 @@
++--------+
+| col0   |
++--------+
+| bird   |
+| dragon |
++--------+
\ No newline at end of file
diff --git a/integration_tests/run_tests.py b/integration_tests/run_tests.py
index 6e2e586..2248458 100755
--- a/integration_tests/run_tests.py
+++ b/integration_tests/run_tests.py
@@ -65,6 +65,8 @@ def RunAll(test_presto=False, test_trino=False):
     RunTest("dialects/trino/joins_test")
     RunTest("dialects/trino/joins_test")
 
+  RunTest("propositional_implication_test")
+
   RunTest("duckdb_negation_test")
   RunTest("duckdb_is_default")
 
diff --git a/parser_py/parse.py b/parser_py/parse.py
index d69cbd5..63ac57d 100755
--- a/parser_py/parse.py
+++ b/parser_py/parse.py
@@ -942,9 +942,9 @@ def ParseProposition(s):
     c = ParsePropositionalEquivalence(s)
     if c:
       return {'conjunction': {'conjunct': [c]}}
-    c = ParsePropositionalImplication(s)
-    if c:
-      return {'conjunction': {'conjunct': [c]}}
+  c = ParsePropositionalImplication(s)
+  if c:
+    return {'conjunction': {'conjunct': [c]}}
 
   c = ParseImplication(s)
   if c: