[SMTChecker] Variables are merged after branches (ite variables)

1 files changed, 39 insertions, 8 deletions

diff --git a/test/libsolidity/SMTChecker.cpp b/test/libsolidity/SMTChecker.cpp
index 3a65aa43..2a1609cc 100644
--- a/test/libsolidity/SMTChecker.cpp
+++ b/test/libsolidity/SMTChecker.cpp
@@ -168,9 +168,9 @@ BOOST_AUTO_TEST_CASE(function_call_does_not_clear_local_vars)
 	CHECK_SUCCESS_NO_WARNINGS(text);
 }
 
-BOOST_AUTO_TEST_CASE(branches_clear_variables)
+BOOST_AUTO_TEST_CASE(branches_merge_variables)
 {
-	// Only clears accessed variables
+	// Branch does not touch variable a
 	string text = R"(
 		contract C {
 			function f(uint x) public pure {
@@ -182,7 +182,7 @@ BOOST_AUTO_TEST_CASE(branches_clear_variables)
 		}
 	)";
 	CHECK_SUCCESS_NO_WARNINGS(text);
-	// It is just a plain clear and will not combine branches.
+	// Positive branch touches variable a, but assertion should still hold.
 	text = R"(
 	contract C {
 			function f(uint x) public pure {
@@ -194,8 +194,8 @@ BOOST_AUTO_TEST_CASE(branches_clear_variables)
 			}
 		}
 	)";
-	CHECK_WARNING(text, "Assertion violation happens here");
-	// Clear also works on the else branch
+	CHECK_SUCCESS_NO_WARNINGS(text);
+	// Negative branch touches variable a, but assertion should still hold.
 	text = R"(
 		contract C {
 			function f(uint x) public pure {
@@ -208,8 +208,8 @@ BOOST_AUTO_TEST_CASE(branches_clear_variables)
 			}
 		}
 	)";
-	CHECK_WARNING(text, "Assertion violation happens here");
-	// Variable is not cleared, if it is only read.
+	CHECK_SUCCESS_NO_WARNINGS(text);
+	// Variable is not merged, if it is only read.
 	text = R"(
 		contract C {
 			function f(uint x) public pure {
@@ -224,6 +224,36 @@ BOOST_AUTO_TEST_CASE(branches_clear_variables)
 		}
 	)";
 	CHECK_SUCCESS_NO_WARNINGS(text);
+	// Variable is reset in both branches
+	text = R"(
+		contract C {
+			function f(uint x) public pure {
+				uint a = 2;
+				if (x > 10) {
+					a = 3;
+				} else {
+					a = 3;
+				}
+				assert(a == 3);
+			}
+		}
+	)";
+	CHECK_SUCCESS_NO_WARNINGS(text);
+	// Variable is reset in both branches
+	text = R"(
+		contract C {
+			function f(uint x) public pure {
+				uint a = 2;
+				if (x > 10) {
+					a = 3;
+				} else {
+					a = 4;
+				}
+				assert(a >= 3);
+			}
+		}
+	)";
+	CHECK_SUCCESS_NO_WARNINGS(text);
 }
 
 BOOST_AUTO_TEST_CASE(branches_assert_condition)
@@ -262,7 +292,7 @@ BOOST_AUTO_TEST_CASE(branches_assert_condition)
 	CHECK_SUCCESS_NO_WARNINGS(text);
 }
 
-BOOST_AUTO_TEST_CASE(ways_to_clear_variables)
+BOOST_AUTO_TEST_CASE(ways_to_merge_variables)
 {
 	string text = R"(
 		contract C {
@@ -275,6 +305,7 @@ BOOST_AUTO_TEST_CASE(ways_to_clear_variables)
 			}
 		}
 	)";
+	CHECK_WARNING(text, "Assertion violation happens here");
 	text = R"(
 		contract C {
 			function f(uint x) public pure {