Initial, working but only with viewport height adjusted a little bit

python/pybug_runtime.py

@@ -0,0 +1,114 @@
+import bdb
+import json
+import sys
+from types import FrameType
+
+
+class PyBugBridgeDebugger(bdb.Bdb):
+    def __init__(self):
+        super().__init__()
+        self.waiting = False
+
+    def send(self, msg: dict):
+        sys.stdout.write(json.dumps(msg) + "\n")
+        sys.stdout.flush()
+
+    def recv(self) -> dict:
+        return json.loads(sys.stdin.readline())
+
+    def user_line(self, frame: FrameType):
+        # print("TRACE:", frame.f_code.co_filename, frame.f_lineno)
+        self.send(
+            {
+                "event": "stopped",
+                "file": frame.f_code.co_filename,
+                "line": frame.f_lineno,
+            }
+        )
+
+        self.interaction_loop(frame)
+
+    def interaction_loop(self, frame: FrameType):
+        while True:
+            cmd = self.recv()
+
+            match cmd["cmd"]:
+                case "continue":
+                    return self.set_continue()
+                case "step":
+                    return self.set_step()
+                case "next":
+                    return self.set_next(frame)
+                case "locals":
+                    self.send(
+                        {
+                            "request_id": cmd["request_id"],
+                            "event": "locals",
+                            "vars": {k: repr(v) for k, v in frame.f_locals.items()},
+                        }
+                    )
+                case "eval":
+                    try:
+                        result = eval(cmd["expr"], frame.f_globals, frame.f_locals)
+                        self.send(
+                            {
+                                "request_id": cmd["request_id"],
+                                "event": "eval",
+                                "status": "ok",
+                                "value": repr(result),
+                            }
+                        )
+                    except Exception as e:
+                        self.send(
+                            {
+                                "request_id": cmd["request_id"],
+                                "event": "eval",
+                                "status": "error",
+                                "value": str(e),
+                            }
+                        )
+                case "break":
+                    err = self.set_break(cmd["file"], cmd["line"])
+                    if err:
+                        self.send(
+                            {
+                                "request_id": cmd["request_id"],
+                                "event": "break",
+                                "status": "error",
+                                "error": err,
+                            }
+                        )
+                    else:
+                        self.send(
+                            {
+                                "request_id": cmd["request_id"],
+                                "event": "break",
+                                "status": "ok",
+                            }
+                        )
+
+
+def main():
+    if len(sys.argv) < 2:
+        print("Usage: pydbug_runtime <script.py>")
+
+    script = sys.argv[1]
+    sys.argv = sys.argv[1:]
+
+    dbg = PyBugBridgeDebugger()
+
+    with open(script, "rb") as f:
+        code = compile(f.read(), script, "exec")
+
+    globals_dict = {
+        "__name__": "__main__",
+        "__file__": script,
+        "__package__": None,
+    }
+
+    dbg.set_step()
+    dbg.run(code, globals_dict, {})
+
+
+if __name__ == "__main__":
+    main()