Add deterministic inference for eagle parity test (#30026)

python/sglang/test/kits/spec_server_kits.py

@@ -161,6 +161,11 @@ class SpecParityKit:
                 "--dtype",
                 cls.dtype,
                 *(["--trust-remote-code"] if cls.trust_remote_code else []),
+                *(
+                    ["--enable-deterministic-inference"]
+                    if cls.enable_deterministic_inference
+                    else []
+                ),
             ],
         )
         try:

python/sglang/test/server_fixtures/spec_eagle_fixture.py

@@ -69,6 +69,7 @@ class SpecEagleServerBase(CustomTestCase):
     # Launch with --enable-return-hidden-states so SpecHiddenStatesKit can probe
     # per-request hidden states; per-request gated, so other requests don't pay.
     enable_return_hidden_states = False
+    enable_deterministic_inference = False
 
     # -- extras --
     # env_overrides: (env_var_obj, value) pairs applied only around launch.
@@ -109,6 +110,8 @@ class SpecEagleServerBase(CustomTestCase):
             args.append("--trust-remote-code")
         if cls.enable_return_hidden_states:
             args.append("--enable-return-hidden-states")
+        if cls.enable_deterministic_inference:
+            args.append("--enable-deterministic-inference")
         if cls.cuda_graph_max_bs_decode is not None:
             args += ["--cuda-graph-max-bs-decode", str(cls.cuda_graph_max_bs_decode)]
         args += [str(a) for a in cls.extra_args]