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TEST FAILURE ANALYSIS claude

Documentation for TEST_FAILURE_ANALYSIS_claude from the Dspex repository.

Looking at the test errors, I can see several design flaws underlying the failures:

1. Session Tracking Initialization Issue

The tests are failing because they expect specific session counts, but the SessionPoolV2 module has an initialization problem:

# In SessionPoolV2.execute_in_session/4
track_session(session_id)

# But track_session expects an ETS table that might not exist
def track_session(session_id) do
  ensure_session_table()
  # ...
end

Design Flaw: The session tracking table creation is not guaranteed to happen before usage, and multiple processes might try to create it simultaneously.

2. Health Check Configuration Mismatch

The tests expect 2 nodes in simulation mode but get 3:

# Test expects: health_data.nodes_total == 2
# Actual: 3

Design Flaw: The node counting logic doesn’t properly distinguish between simulated and real nodes. The health check operation seems to be including the local node in the count even in simulation mode.

3. Process List Operation Inconsistency

# Test expects: length(process_data.nodes_queried) == 2
# Actual: 3

Design Flaw: Similar to the health check issue, the process list operation is querying more nodes than expected, suggesting the simulation mode isn’t properly isolating operations.

4. Mode Switching Logic Problem

# Test expects: length(updated_status.nodes) == 3
# Actual: 1

Design Flaw: The mode switching between single-node and multi-node operation isn’t working correctly. The tool manager isn’t properly transitioning between modes based on cluster state.

5. Node Discovery in Simulation Mode

The node_not_found error suggests:

{:error, :node_not_found}

Design Flaw: The node info operation is trying to query nodes that don’t exist in simulation mode, indicating the simulation isn’t properly mocking node existence.

6. Process Distribution Calculation

# Test expects: map_size(process_dist) == 4
# Actual: 1

Design Flaw: The process distribution calculation in simulation mode isn’t creating the expected distribution across simulated nodes.

7. Real Node Tests Failing Due to Distribution

** (ErlangError) Erlang error: :not_alive

Design Flaw: The tests are trying to start distributed Erlang nodes without the VM being in distributed mode. The test setup doesn’t properly handle the case where distribution isn’t available.

8. Deprecated Function Warning

warning: :slave.start_link/2 is deprecated. It will be removed in OTP 29. Use the 'peer' module instead

Design Flaw: Using deprecated APIs that will break in future Erlang/OTP versions.

Root Causes Summary:

  1. Race Conditions: Multiple processes trying to initialize shared resources (ETS tables) without proper synchronization.

  2. Unclear Separation of Concerns: The simulation mode isn’t clearly separated from real mode, causing operations to leak between contexts.

  3. Implicit State Dependencies: The code assumes certain state (like node names, ETS tables) exists without ensuring it’s initialized.

  4. Hardcoded Assumptions: The tests have hardcoded expectations about node counts and behavior that don’t match the actual implementation.

  5. Missing Abstraction Layer: There’s no clear abstraction between simulated and real distributed operations, leading to confusion about which mode is active.

  6. Environment Dependencies: The code doesn’t properly handle cases where the Erlang VM isn’t started in distributed mode.

  1. Initialize ETS tables in a supervised process to avoid race conditions
  2. Create clear interfaces for simulated vs. real operations
  3. Use dependency injection for node discovery and counting
  4. Replace deprecated :slave module with :peer
  5. Add proper guards for distributed mode operations
  6. Implement proper mode isolation to prevent cross-mode interference