Merge pull request #67264 from rintaro/parameter-pack-precedence-test

[Parse] Add an executable test for parameter pack pasing

Author: rintaro

test/Parse/type_parameter_packs_executable.swift

@@ -0,0 +1,19 @@
+// REQUIRES: executable_test
+// RUN: %target-run-simple-swift
+
+import StdlibUnittest
+
+var suite = TestSuite("ParameterPackTestSuite")
+
+suite.test("operator precedence") {
+  // Test 'a * each b + c' is parsed and operator-folded as '(a * (each b)) + c'
+  func _test<each T: Numeric>(args arg: repeat each T) -> (repeat each T) {
+    (repeat 2 * each arg + 3)
+  }
+
+  let result = _test(args: 12, 12.3)
+  expectEqual(result.0, 2 * 12 + 3)
+  expectEqual(result.1, 2 * 12.3 + 3)
+}
+
+runAllTests()