[lldb] Disable auto fix-its when evaluating expressions in the test suite

Summary:
Currently the test suite runs with enabled automatically applied Clang fix-its for expressions.
This is causing that sometimes incorrect expressions in tests are still evaluated even though they
are actually incorrect. Let's disable this feature in the test suite so that we know when expressions
are wrong and leave the fix-it testing to the dedicated tests for that feature.

Also updates the `lang/cpp/operators/` test as it seems Clang needs the `struct` keywords
before C and would otherwise fail without fixits.

Reviewers: jingham, JDevlieghere, shafik

Reviewed By: JDevlieghere, shafik

Subscribers: shafik, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D74957

lldb/packages/Python/lldbsuite/test/lldbtest.py

@@ -692,6 +692,10 @@ class Base(unittest2.TestCase):
             # differ in the debug info, which is not being hashed.
             "settings set symbols.enable-external-lookup false",
 
+            # Disable fix-its by default so that incorrect expressions in tests don't
+            # pass just because Clang thinks it has a fix-it.
+            "settings set target.auto-apply-fixits false",
+
             # Testsuite runs in parallel and the host can have also other load.
             "settings set plugin.process.gdb-remote.packet-timeout 60",
 
@@ -2394,7 +2398,16 @@ FileCheck output:
         self.assertTrue(expr.strip() == expr, "Expression contains trailing/leading whitespace: '" + expr + "'")
 
         frame = self.frame()
-        eval_result = frame.EvaluateExpression(expr)
+        options = lldb.SBExpressionOptions()
+
+        # Disable fix-its that tests don't pass by accident.
+        options.SetAutoApplyFixIts(False)
+
+        # Set the usual default options for normal expressions.
+        options.SetIgnoreBreakpoints(True)
+        options.SetLanguage(frame.GuessLanguage())
+
+        eval_result = frame.EvaluateExpression(expr, options)
 
         if error_msg:
             self.assertFalse(eval_result.IsValid(), "Unexpected success with result: '" + str(eval_result) + "'")

lldb/test/API/lang/cpp/operators/main.cpp

@@ -171,7 +171,7 @@ int main(int argc, char **argv) {
   //% self.expect("expr static_cast<long>(c)", endstr=" 12\n")
   //% self.expect("expr c.operatorint()", endstr=" 13\n")
   //% self.expect("expr c.operatornew()", endstr=" 14\n")
-  //% self.expect("expr (new C)->custom_new", endstr=" true\n")
+  //% self.expect("expr (new struct C)->custom_new", endstr=" true\n")
   //% self.expect("expr (new struct C[1])->custom_new", endstr=" true\n")
   //% self.expect("expr delete c2; side_effect", endstr=" = 1\n")
   //% self.expect("expr delete[] c3; side_effect", endstr=" = 2\n")

lldb/test/Shell/lit-lldb-init.in

@@ -3,3 +3,4 @@ settings set symbols.enable-external-lookup false
 settings set plugin.process.gdb-remote.packet-timeout 60
 settings set interpreter.echo-comment-commands false
 settings set symbols.clang-modules-cache-path "@LLDB_TEST_MODULE_CACHE_LLDB@"
+settings set target.auto-apply-fixits false