Remove checks for `None` for fields which should never be `None` (#17985)

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

vllm/config.py

@@ -4282,25 +4282,22 @@ class VllmConfig:
             self.model_config.verify_dual_chunk_attention_config(
                 self.load_config)
 
-        if self.cache_config is not None:
-            self.cache_config.verify_with_parallel_config(self.parallel_config)
+        self.cache_config.verify_with_parallel_config(self.parallel_config)
 
-        if self.lora_config:
+        if self.lora_config is not None:
             self.lora_config.verify_with_cache_config(self.cache_config)
             self.lora_config.verify_with_model_config(self.model_config)
             self.lora_config.verify_lora_support()
-        if self.prompt_adapter_config:
+        if self.prompt_adapter_config is not None:
             self.prompt_adapter_config.verify_with_model_config(
                 self.model_config)
 
-        if self.quant_config is None and \
-            self.model_config is not None and self.load_config is not None:
+        if self.quant_config is None and self.model_config is not None:
             self.quant_config = VllmConfig._get_quantization_config(
                 self.model_config, self.load_config)
 
         from vllm.platforms import current_platform
-        if self.scheduler_config is not None and \
-            self.model_config is not None and \
+        if self.model_config is not None and \
             self.scheduler_config.chunked_prefill_enabled and \
             self.model_config.dtype == torch.float32 and \
             current_platform.get_device_capability() == (7, 5):
@@ -4335,8 +4332,7 @@ class VllmConfig:
 
         self._set_cudagraph_sizes()
 
-        if self.cache_config is not None and \
-            self.cache_config.cpu_offload_gb > 0 and \
+        if self.cache_config.cpu_offload_gb > 0 and \
             self.compilation_config.level != CompilationLevel.NO_COMPILATION \
                 and not envs.VLLM_USE_V1:
             logger.warning(
@@ -4358,16 +4354,16 @@ class VllmConfig:
                 "full_cuda_graph is not supported with "
                 "cascade attention. Disabling cascade attention.")
             self.model_config.disable_cascade_attn = True
-            if self.cache_config is not None:
-                self.cache_config.enable_prefix_caching = False
+            self.cache_config.enable_prefix_caching = False
 
-        if (self.kv_events_config
+        if (self.kv_events_config is not None
                 and self.kv_events_config.enable_kv_cache_events
                 and not self.cache_config.enable_prefix_caching):
             logger.warning(
                 "KV cache events are on, but prefix caching is not enabled."
                 "Use --enable-prefix-caching to enable.")
-        if (self.kv_events_config and self.kv_events_config.publisher != "null"
+        if (self.kv_events_config is not None
+                and self.kv_events_config.publisher != "null"
                 and not self.kv_events_config.enable_kv_cache_events):
             logger.warning("KV cache events are disabled,"
                            "but the scheduler is configured to publish them."