From 6f456024c37424d9c8cc1cea07126a28f246588d Mon Sep 17 00:00:00 2001
From: Adrian Vogelsgesang <avogelsgesang@salesforce.com>
Date: Wed, 21 Aug 2024 08:25:57 +0200
Subject: [PATCH] [lldb-dap] Mark hidden frames as "subtle" (#105457)

This commit takes advantage of the recently introduced
`SBFrame::IsHidden` to show those hidden frames as "subtle" frames in
the UI. E.g., VS Code hides those stack frames by default, and renders
them as grayed out frames, in case the user decides to show them in the
stack trace
---
 .../lldb-dap/stackTrace/subtleFrames/Makefile |  3 ++
 .../subtleFrames/TestDAP_subtleFrames.py      | 29 +++++++++++++++++++
 .../lldb-dap/stackTrace/subtleFrames/main.cpp | 13 +++++++++
 lldb/tools/lldb-dap/JSONUtils.cpp             |  3 ++
 4 files changed, 48 insertions(+)
 create mode 100644 lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/Makefile
 create mode 100644 lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/TestDAP_subtleFrames.py
 create mode 100644 lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/main.cpp

diff --git a/lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/Makefile b/lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/Makefile
new file mode 100644
index 00000000000000..99998b20bcb050
--- /dev/null
+++ b/lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/Makefile
@@ -0,0 +1,3 @@
+CXX_SOURCES := main.cpp
+
+include Makefile.rules
diff --git a/lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/TestDAP_subtleFrames.py b/lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/TestDAP_subtleFrames.py
new file mode 100644
index 00000000000000..1e41e841e39bc8
--- /dev/null
+++ b/lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/TestDAP_subtleFrames.py
@@ -0,0 +1,29 @@
+"""
+Test lldb-dap stack trace response
+"""
+
+
+import dap_server
+from lldbsuite.test.decorators import *
+
+import lldbdap_testcase
+from lldbsuite.test.lldbtest import *
+
+
+class TestDAP_subtleFrames(lldbdap_testcase.DAPTestCaseBase):
+    @add_test_categories(["libc++"])
+    def test_subtleFrames(self):
+        """
+        Internal stack frames (such as the ones used by `std::function`) are marked as "subtle".
+        """
+        program = self.getBuildArtifact("a.out")
+        self.build_and_launch(program)
+        source = "main.cpp"
+        self.set_source_breakpoints(source, [line_number(source, "BREAK HERE")])
+        self.continue_to_next_stop()
+
+        frames = self.get_stackFrames()
+        for f in frames:
+            if "__function" in f["name"]:
+                self.assertEqual(f["presentationHint"], "subtle")
+        self.assertTrue(any(f.get("presentationHint") == "subtle" for f in frames))
diff --git a/lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/main.cpp b/lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/main.cpp
new file mode 100644
index 00000000000000..71944528441e38
--- /dev/null
+++ b/lldb/test/API/tools/lldb-dap/stackTrace/subtleFrames/main.cpp
@@ -0,0 +1,13 @@
+#include <functional>
+#include <iostream>
+
+void greet() {
+  // BREAK HERE
+  std::cout << "Hello\n";
+}
+
+int main() {
+  std::function<void()> func{greet};
+  func();
+  return 0;
+}
diff --git a/lldb/tools/lldb-dap/JSONUtils.cpp b/lldb/tools/lldb-dap/JSONUtils.cpp
index a8b85f55939e17..c080fd395b7288 100644
--- a/lldb/tools/lldb-dap/JSONUtils.cpp
+++ b/lldb/tools/lldb-dap/JSONUtils.cpp
@@ -763,6 +763,9 @@ llvm::json::Value CreateStackFrame(lldb::SBFrame &frame) {
     object.try_emplace("instructionPointerReference", formatted_addr);
   }
 
+  if (frame.IsArtificial() || frame.IsHidden())
+    object.try_emplace("presentationHint", "subtle");
+
   return llvm::json::Value(std::move(object));
 }