UE 5.7: blocks_genprojfiles_vscode.bat fails — launch.json no longer written to .vscode/ (moved into .code-workspace)

[rennsport-007]

Bug report

• Project AirSim Version/#commit: main branch, cloned July 2026
• autopilot version: N/A
• OS Version: Windows 10.0.26200.8457

What's the issue you encountered?

Running unreal\Blocks\blocks_genprojfiles_vscode.bat on a clean checkout with UE 5.7 fails at the final Python step with a FileNotFoundError because .vscode\launch.json is never created.

Root cause: UE 5.7 changed VSCodeProjectFileGenerator.cs (Engine\Source\Programs\UnrealBuildTool\ProjectFiles\VisualStudioCode\VSCodeProjectFileGenerator.cs) so that WriteTasks() and WriteLaunch() now write directly into the "tasks" and "launch" keys of the generated .code-workspace file, instead of writing standalone .vscode\tasks.json / .vscode\launch.json files (the behavior in UE 5.2 and earlier). Relevant snippet from UE 5.7's generator:
WorkspaceFile.BeginObject("tasks");
WriteTasks(WorkspaceFile, ProjectData);
WorkspaceFile.EndObject();
WorkspaceFile.BeginObject("launch");
WriteLaunch(WorkspaceFile, ProjectData, Logger);
WorkspaceFile.EndObject();
...
WorkspaceFile.Write(FileReference.Combine(PrimaryProjectPath, WorkspaceName + ".code-workspace"));

Since blocks_genprojfiles_vscode.bat's for /f rename loop and tools\update_blocks_vscode.py both assume a standalone .vscode\launch.json exists (matching UE ≤5.2 behavior), both fail on a clean UE 5.7 setup — even though the repo's own docs list UE 5.7 as officially supported.

Settings

N/A

How can the issue be reproduced?

1. Set UE_ROOT to a UE 5.7 install (5.7.4 in my case)
2. Clone repo, run unreal\Blocks\blocks_genprojfiles_vscode.bat (no sim libs need to be built first — reproduces either way)
3. UBT reports Result: Succeeded and generates Blocks.code-workspace, c_cpp_properties.json, and compileCommands_*.json inside .vscode\
4. .vscode\launch.json is never created
5. Script fails with the error below

Include full error message in text form

1 file(s) moved.

The system cannot find the file .vscode\launch.json.
The system cannot find the file specified.
Traceback (most recent call last):
File "...\unreal\Blocks....\tools\update_blocks_vscode.py", line 87, in
main()
File "...\unreal\Blocks....\tools\update_blocks_vscode.py", line 82, in main
update_launch_json(vscode_dir)
File "...\unreal\Blocks....\tools\update_blocks_vscode.py", line 43, in update_launch_json
launch = json.loads(launch_path.read_text(encoding="utf-8"))
FileNotFoundError: [Errno 2] No such file or directory: '...\unreal\Blocks.vscode\launch.json'

Suggested fix

Before the existing for /f rename loop in blocks_genprojfiles_vscode.bat, extract the "launch" section out of the generated .code-workspace file into a standalone .vscode\launch.json (written without a UTF-8 BOM, since Python's default utf-8 decoder throws on one):

if not exist .vscode mkdir .vscode
powershell -NoProfile -Command "$ws = Get-Content -Raw '.\Blocks.code-workspace' | ConvertFrom-Json; $json = $ws.launch | ConvertTo-Json -Depth 10; [System.IO.File]::WriteAllText((Join-Path (Get-Location) '.vscode\launch.json'), $json, [System.Text.UTF8Encoding]::new($false))"

Additionally, tools\update_blocks_vscode.py line 43 should decode with utf-8-sig instead of utf-8, as a defensive measure against BOM-prefixed JSON from any source:

launch = json.loads(launch_path.read_text(encoding="utf-8-sig"))