[eric] browser: unit and end-to-end loop tests for the new browser behaviors

backend/tests/test_browser_validator.py

@@ -0,0 +1,64 @@
+"""Aux-LLM stuck-adjudication for the browser sub-agent."""
+
+import asyncio
+
+from backend.apps.agents.browser.browser_validator import adjudicate_stuck, _extract_text
+
+
+class _Block:
+    def __init__(self, type_, text=""):
+        self.type = type_
+        self.text = text
+
+
+class _Resp:
+    def __init__(self, blocks):
+        self.content = blocks
+
+
+class _FakeClient:
+    """Minimal Anthropic-shaped client: client.messages.create(...)."""
+
+    def __init__(self, resp=None, raise_exc=None):
+        self._resp = resp
+        self._raise = raise_exc
+        self.calls = []
+        self.messages = self
+
+    async def create(self, **kwargs):
+        self.calls.append(kwargs)
+        if self._raise:
+            raise self._raise
+        return self._resp
+
+
+def test_returns_extracted_guidance_and_assembles_prompt():
+    fc = _FakeClient(resp=_Resp([_Block("text", "Press Tab then Enter to focus the field.")]))
+    out = asyncio.run(adjudicate_stuck(fc, "cheap-model", "share the doc", "- click -> not found", "the page"))
+    assert out == "Press Tab then Enter to focus the field."
+    call = fc.calls[0]
+    assert call["model"] == "cheap-model"
+    assert call["max_tokens"] == 300
+    prompt = call["messages"][0]["content"]
+    assert "share the doc" in prompt
+    assert "not found" in prompt
+
+
+def test_swallows_provider_error_and_returns_empty():
+    fc = _FakeClient(raise_exc=RuntimeError("429 rate limited"))
+    out = asyncio.run(adjudicate_stuck(fc, "m", "g", "r", "p"))
+    assert out == ""
+
+
+def test_extract_text_joins_text_blocks_and_ignores_others():
+    resp = _Resp([_Block("text", "First."), _Block("tool_use"), _Block("text", "Second.")])
+    assert _extract_text(resp) == "First. Second."
+
+
+def test_handles_empty_inputs_without_crashing():
+    fc = _FakeClient(resp=_Resp([_Block("text", "ok")]))
+    out = asyncio.run(adjudicate_stuck(fc, "m", "", "", ""))
+    assert out == "ok"
+    # placeholders keep the prompt well-formed
+    prompt = fc.calls[0]["messages"][0]["content"]
+    assert "(unknown)" in prompt and "(none)" in prompt and "(empty)" in prompt