[lldb][test] Move std::function from libcxx to generic directory (#147701)

This just moves the test from `libcxx` to `generic`. There are currently
no `std::function` formatters for libstdc++ so I didn't add a test-case
for it.

Split out from llvm/llvm-project#146740

Author: Michael137

lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/function/Makefile renamed to lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/function/Makefile

@@ -1,5 +1,3 @@
 CXX_SOURCES := main.cpp
-CXXFLAGS_EXTRAS := -std=c++11
-USE_LIBCPP := 1
 
 include Makefile.rules

lldb/test/API/functionalities/data-formatter/data-formatter-stl/libcxx/function/TestLibCxxFunction.py renamed to lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/function/TestDataFormatterStdFunction.py

@@ -2,14 +2,13 @@
 Test lldb data formatter subsystem.
 """
 
-
 import lldb
 from lldbsuite.test.decorators import *
 from lldbsuite.test.lldbtest import *
 from lldbsuite.test import lldbutil
 
 
-class LibCxxFunctionTestCase(TestBase):
+class StdFunctionTestCase(TestBase):
     # Run frame var for a variable twice. Verify we do not hit the cache
     # the first time but do the second time.
     def run_frame_var_check_cache_use(
@@ -34,10 +33,8 @@ def run_frame_var_check_cache_use(
             substrs=["lldb_private::CompileUnit::FindFunction"],
         )
 
-    @add_test_categories(["libc++"])
-    def test(self):
-        """Test that std::function as defined by libc++ is correctly printed by LLDB"""
-        self.build()
+    def do_test(self):
+        """Test that std::function is correctly printed by LLDB"""
         self.runCmd("file " + self.getBuildArtifact("a.out"), CURRENT_EXECUTABLE_SET)
 
         bkpt = self.target().FindBreakpointByID(
@@ -56,20 +53,20 @@ def test(self):
         )
 
         self.run_frame_var_check_cache_use(
-            "foo2_f", "Lambda in File main.cpp at Line 22"
+            "foo2_f", "Lambda in File main.cpp at Line 16"
         )
 
         lldbutil.continue_to_breakpoint(self.process(), bkpt)
 
         self.run_frame_var_check_cache_use(
-            "add_num2_f", "Lambda in File main.cpp at Line 13"
+            "add_num2_f", "Lambda in File main.cpp at Line 9"
         )
 
         lldbutil.continue_to_breakpoint(self.process(), bkpt)
 
-        self.run_frame_var_check_cache_use("f2", "Lambda in File main.cpp at Line 35")
+        self.run_frame_var_check_cache_use("f2", "Lambda in File main.cpp at Line 26")
         self.run_frame_var_check_cache_use(
-            "f3", "Lambda in File main.cpp at Line 39", True
+            "f3", "Lambda in File main.cpp at Line 30", True
         )
         # TODO reenable this case when std::function formatter supports
         # general callable object case.
@@ -82,3 +79,8 @@ def test(self):
         self.expect(
             "frame variable f5", substrs=["f5 =  Function = Bar::add_num(int) const"]
         )
+
+    @add_test_categories(["libc++"])
+    def test_libcxx(self):
+        self.build(dictionary={"USE_LIBCPP": 1})
+        self.do_test()

lldb/test/API/functionalities/data-formatter/data-formatter-stl/generic/function/main.cpp

@@ -0,0 +1,43 @@
+#include <functional>
+
+int foo(int x, int y) { return x + y - 1; }
+
+struct Bar {
+  int operator()() { return 66; }
+  int add_num(int i) const { return i + 3; }
+  int add_num2(int i) {
+    std::function<int(int)> add_num2_f = [](int x) { return x + 1; };
+
+    return add_num2_f(i); // Set break point at this line.
+  }
+};
+
+int foo2() {
+  auto f = [](int x) { return x + 1; };
+
+  std::function<int(int)> foo2_f = f;
+
+  return foo2_f(10); // Set break point at this line.
+}
+
+int main(int argc, char *argv[]) {
+  int acc = 42;
+  std::function<int(int, int)> f1 = foo;
+  std::function<int(int)> f2 = [acc, f1](int x) -> int {
+    return x + f1(acc, x);
+  };
+
+  auto f = [](int x, int y) { return x + y; };
+  auto g = [](int x, int y) { return x * y; };
+  std::function<int(int, int)> f3 = argc % 2 ? f : g;
+
+  Bar bar1;
+  std::function<int()> f4(bar1);
+  std::function<int(const Bar &, int)> f5 = &Bar::add_num;
+
+  int foo2_result = foo2();
+  int bar_add_num2_result = bar1.add_num2(10);
+
+  return f1(acc, acc) + f2(acc) + f3(acc + 1, acc + 2) + f4() +
+         f5(bar1, 10); // Set break point at this line.
+}