Add tests for job-log excerpting

Covers the three call sites that show a job stream to a model: get_job_details,
_format_job_context (which re-slices an already-excerpted value down to 500
characters of head), and the get_job_errors tool result.

test/unit/app/managers/test_AgentOperationsManager.py

@@ -2,6 +2,7 @@ from unittest import mock
 
 import pytest
 
+from galaxy.agents.base import JOB_LOG_EXCERPT_CHARS
 from galaxy.agents.operations import AgentOperationsManager
 from galaxy.schema.fields import Security
 from .base import BaseTestCase
@@ -157,6 +158,61 @@ class TestAgentOperationsManagerWithMockedServices(BaseTestCase):
         assert result["collection"]["elements_truncated"] is True
         assert result["collection"]["total_elements"] == 10
 
+    def test_get_job_errors_keeps_both_ends_of_a_long_log(self):
+        """The failure is at the tail, so a head slice would drop the useful part."""
+        job = mock.MagicMock()
+        job.stderr = "HEAD_MARKER\n" + ("noise\n" * 5000) + "TAIL_MARKER: out of memory"
+        job.stdout = "short stdout"
+        job.info = "short info"
+        job.tool_id = "ngm"
+        job.tool_version = "1.0"
+        job.state = "error"
+        job.exit_code = 137
+        job.id = 42
+
+        hda = mock.MagicMock()
+        hda.creating_job = job
+
+        with (
+            mock.patch.object(self.agent_ops.hda_manager, "get_accessible", return_value=hda),
+            mock.patch.object(self.trans.security, "decode_id", return_value=123),
+            mock.patch.object(self.trans.security, "encode_id", return_value="enc42"),
+        ):
+            result = self.agent_ops.get_job_errors("encoded_dataset_id")
+
+        assert len(result["stderr"]) <= JOB_LOG_EXCERPT_CHARS
+        assert "HEAD_MARKER" in result["stderr"]
+        assert "TAIL_MARKER" in result["stderr"]
+        assert result["truncated"] is True
+        # Streams that fit are passed through untouched.
+        assert result["stdout"] == "short stdout"
+        assert result["info"] == "short info"
+
+    def test_get_job_errors_counts_info_toward_the_truncated_flag(self):
+        """Job.info is a TrimmedString(255), but that only trims on the way to the DB."""
+        job = mock.MagicMock()
+        job.stderr = "short stderr"
+        job.stdout = "short stdout"
+        job.info = "I" * 50000
+        job.tool_id = "ngm"
+        job.tool_version = "1.0"
+        job.state = "error"
+        job.exit_code = 1
+        job.id = 42
+
+        hda = mock.MagicMock()
+        hda.creating_job = job
+
+        with (
+            mock.patch.object(self.agent_ops.hda_manager, "get_accessible", return_value=hda),
+            mock.patch.object(self.trans.security, "decode_id", return_value=123),
+            mock.patch.object(self.trans.security, "encode_id", return_value="enc42"),
+        ):
+            result = self.agent_ops.get_job_errors("encoded_dataset_id")
+
+        assert len(result["info"]) <= JOB_LOG_EXCERPT_CHARS
+        assert result["truncated"] is True
+
     def test_get_workflow_details_with_version(self):
         mock_workflow = mock.MagicMock()
 

test/unit/app/test_agents.py

@@ -551,6 +551,38 @@ class TestAgentUnitMocked:
         assert response.metadata["query_truncated"] is True
         assert response.metadata["original_query_length"] == 40000
 
+    def test_format_job_context_does_not_reslice_an_excerpted_log(self):
+        """get_job_details already budgeted this stream; slicing again drops its tail.
+
+        The old 500-char head slice made that budget dead code -- only the first few
+        lines of a failing tool's banner ever reached the model.
+        """
+        agent = ErrorAnalysisAgent(self.deps)
+        stderr = "HEAD_MARKER" + ("x" * 1500) + "TAIL_MARKER"
+
+        rendered = agent._format_job_context({"tool_id": "ngm", "state": "error", "stderr": stderr})
+
+        assert "HEAD_MARKER" in rendered
+        assert "TAIL_MARKER" in rendered
+
+    @pytest.mark.asyncio
+    async def test_get_job_details_keeps_the_tail_of_a_long_stderr(self):
+        """A head slice here would drop the traceback before the prompt is ever built."""
+        agent = ErrorAnalysisAgent(self.deps)
+        job = mock.MagicMock()
+        job.stderr = "HEAD_MARKER\n" + ("noise\n" * 5000) + "TAIL_MARKER: killed"
+        job.stdout = ""
+        job.id = 42
+
+        self.deps.job_manager = mock.Mock()
+        self.deps.job_manager.get_accessible_job.return_value = job
+
+        details = await agent.get_job_details(42)
+
+        assert len(details["stderr"]) <= agents_base.JOB_LOG_EXCERPT_CHARS
+        assert "HEAD_MARKER" in details["stderr"]
+        assert "TAIL_MARKER" in details["stderr"]
+
     @pytest.mark.asyncio
     async def test_error_analysis_trims_oversized_stderr_instead_of_rejecting(self):
         """A huge stderr dump gets trimmed and analyzed rather than refused for length.