Add single-call measurement for prepared investigation prompts

tests/test_prompt_probe.py

@@ -0,0 +1,36 @@
+import copy
+import pytest
+from viano_bug_analysis.prompt_probe import prepare
+from viano_bug_analysis.minimal_prompt_test import measure
+from viano_bug_analysis.llm import LLMError
+from test_minimal_prompt_test import provider
+
+
+def request():return {'prompt_version':'fixture','messages':[{'role':'system','content':'Test instructions'},
+    {'role':'user','content':'Test context'}], 'output_schema':{'type':'object','required':['query'],
+    'properties':{'query':{'const':'database.schema'}},'additionalProperties':False}}
+
+
+def test_native_schema_sent_once_without_wrapper_or_tools():
+    r=request();before=copy.deepcopy(r);case=prepare(provider(),r)
+    payload=case['payload']
+    assert set(payload)=={'systemInstruction','contents','generationConfig'}
+    assert payload['contents'][0]['parts'][0]['text']=='Test context'
+    assert payload['generationConfig']['responseJsonSchema']==r['output_schema']
+    assert payload['generationConfig']['thinkingConfig']=={'thinkingLevel':'low'}
+    assert r==before
+
+
+def test_validates_the_prepared_schema_not_the_minimal_test_schema():
+    case=prepare(provider(),request())
+    def post(*args):return {'candidates':[{'finishReason':'STOP','content':{'parts':[{'text':'{"query":"database.schema"}'}]}}],
+        'usageMetadata':{'promptTokenCount':200,'candidatesTokenCount':8,'thoughtsTokenCount':30}}
+    result=measure(provider(),case,10000,post)
+    assert result['status']=='SUCCESS' and result['schema_valid']
+    assert result['usage']['input_tokens']==200
+
+
+@pytest.mark.parametrize('field,value',[('messages',[]),('messages',[{'role':'user','content':'x'}])])
+def test_rejects_invalid_envelopes(field,value):
+    r=request();r[field]=value
+    with pytest.raises(LLMError):prepare(provider(),r)