TestEngine: fixed issue with capture tool accessing erroneous stack data.

Author: ocornut

docs/CHANGELOG.txt

@@ -5,6 +5,9 @@ CHANGELOG
    Those changes are not all listed here.
 ** For a while this is going to ONLY INCLUDE BREAKING CHANGES.
 
+2025/04/24:
+- TestEngine: fixed crash/issue in capture tool.
+
 2025/03/17:
 - TestEngine: *BREAKING* reworked ImGuiTestEngine_GetResult() as ImGuiTestEngine_GetResultSummary()
   outputting a structure where we can add more fields.

imgui_test_engine/imgui_capture_tool.cpp

@@ -206,6 +206,7 @@ void ImGuiCaptureContext::PreRender()
     if (IsCapturing())
     {
         const ImGuiCaptureArgs* args = _CaptureArgs;
+        IM_ASSERT(args != NULL);
         g.IO.MouseDrawCursor = !(args->InFlags & ImGuiCaptureFlags_HideMouseCursor);
     }
 }
@@ -618,6 +619,7 @@ void ImGuiCaptureContext::EndVideoCapture()
     IM_ASSERT(_VideoRecording == true);
 
     _VideoRecording = false;
+    _CaptureArgs = nullptr;
 }
 
 bool ImGuiCaptureContext::IsCapturingVideo()

imgui_test_engine/imgui_te_engine.cpp

@@ -1639,6 +1639,7 @@ void ImGuiTestEngine_RunTest(ImGuiTestEngine* engine, ImGuiTestContext* parent_c
             test_output->EndTime = test_output->StartTime;
         ctx->Test = nullptr;
         ctx->TestOutput = nullptr;
+        ctx->CaptureArgs = nullptr;
         return;
     }
 
@@ -1921,6 +1922,11 @@ void ImGuiTestEngine_RunTest(ImGuiTestEngine* engine, ImGuiTestContext* parent_c
         }
     }
 
+    // 'ctx' at this point is either a local variable or shared with parent.
+    //ctx->Test = nullptr;
+    //ctx->TestOutput = nullptr;
+    //ctx->CaptureArgs = nullptr;
+
     IM_ASSERT(engine->TestContext == ctx);
     engine->TestContext = parent_ctx;
 }