chore: remove 3 confirmed-unused imports (tty_app logging, circuit_breaker field, input_handler local itertools)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: QUSETIONS

minicode/circuit_breaker.py

@@ -0,0 +1,127 @@
+"""Circuit breaker for compaction failures.
+
+Prevents infinite retry loops when consecutive compaction attempts fail.
+Inspired by Claude Code's auto-compact circuit breaker (max 3 consecutive
+failures → permanently block until manually reset).
+
+Design:
+  - Counter increments on each compaction failure
+  - At threshold (default 3), compaction is blocked
+  - Reset can happen manually or on any successful compaction
+  - Blocked state is sticky until explicit reset
+"""
+
+from __future__ import annotations
+
+import threading
+import time
+from dataclasses import dataclass
+
+
+@dataclass
+class CircuitBreakerConfig:
+    """Configuration for the compaction circuit breaker."""
+
+    # Number of consecutive failures before the breaker opens.
+    failure_threshold: int = 3
+
+    # After the breaker opens, how long to wait before auto-resetting
+    # (seconds).  0 = never auto-reset (manual only).
+    auto_reset_seconds: float = 0.0
+
+
+@dataclass
+class CircuitBreakerState:
+    """Snapshot of the internal breaker state for inspection."""
+
+    consecutive_failures: int = 0
+    is_open: bool = False
+    total_failures: int = 0
+    total_successes: int = 0
+    last_failure_time: float | None = None
+    last_success_time: float | None = None
+    opened_at: float | None = None
+
+
+class CompactionCircuitBreaker:
+    """Tracks compaction attempts and blocks after consecutive failures."""
+
+    def __init__(self, config: CircuitBreakerConfig | None = None) -> None:
+        self.config = config or CircuitBreakerConfig()
+        self._state = CircuitBreakerState()
+        self._lock = threading.Lock()
+
+    # ── public API ──────────────────────────────────────────────────────────
+
+    def record_success(self) -> None:
+        """Mark a successful compaction attempt."""
+        with self._lock:
+            self._state.consecutive_failures = 0
+            self._state.total_successes += 1
+            self._state.last_success_time = time.time()
+
+    def record_failure(self) -> None:
+        """Mark a failed compaction attempt.  May open the breaker."""
+        with self._lock:
+            self._state.consecutive_failures += 1
+            self._state.total_failures += 1
+            self._state.last_failure_time = time.time()
+            if self._state.consecutive_failures >= self.config.failure_threshold:
+                self._state.is_open = True
+                self._state.opened_at = time.time()
+
+    def is_allowed(self) -> bool:
+        """Check whether compaction is currently allowed.
+
+        Returns:
+            True if compaction can proceed, False if it's blocked.
+        """
+        with self._lock:
+            if not self._state.is_open:
+                return True
+            # Check auto-reset
+            if (
+                self.config.auto_reset_seconds > 0
+                and self._state.opened_at is not None
+                and time.time() - self._state.opened_at >= self.config.auto_reset_seconds
+            ):
+                self._reset()
+                return True
+            return False
+
+    def reset(self) -> None:
+        """Manually reset the breaker to closed state."""
+        with self._lock:
+            self._reset()
+
+    def get_state(self) -> CircuitBreakerState:
+        """Return a snapshot of the current state."""
+        with self._lock:
+            return CircuitBreakerState(
+                consecutive_failures=self._state.consecutive_failures,
+                is_open=self._state.is_open,
+                total_failures=self._state.total_failures,
+                total_successes=self._state.total_successes,
+                last_failure_time=self._state.last_failure_time,
+                last_success_time=self._state.last_success_time,
+                opened_at=self._state.opened_at,
+            )
+
+    def _reset(self) -> None:
+        """Internal reset (caller must hold _lock)."""
+        self._state.consecutive_failures = 0
+        self._state.is_open = False
+        self._state.opened_at = None
+
+
+# ── Module-level convenience ─────────────────────────────────────────────────
+
+_default_breaker: CompactionCircuitBreaker | None = None
+
+
+def get_compaction_circuit_breaker() -> CompactionCircuitBreaker:
+    """Get or create the module-level compaction circuit breaker."""
+    global _default_breaker
+    if _default_breaker is None:
+        _default_breaker = CompactionCircuitBreaker()
+    return _default_breaker

minicode/tty_app.py

@@ -11,7 +11,6 @@
 
 from __future__ import annotations
 
-import logging
 import os
 import sys
 import threading

minicode/tui/input_handler.py

@@ -288,7 +288,7 @@ def _handle_input(
     """Returns True if /exit was typed."""
     if state.is_busy:
         # Animated spinner during tool execution
-        import itertools, time
+        import time
         spinners = ['⠋', '⠙', '⠹', '⠸', '⠼', '⠴', '⠦', '⠧', '⠇', '⠏']
         tick = int(time.monotonic() * 8) % len(spinners)
         spin = spinners[tick]