refactor: move format_duration to _output module to reduce coupling

The format_duration utility was defined in engine.py but is a pure
formatting function unrelated to the engine's run-loop logic. This
forced _console_emitter.py to import from engine.py, creating an
unnecessary dependency between the rendering layer and the engine.

Moved to _output.py where formatting utilities already live, and
consolidated duplicate tests (previously in both test_cli.py and
test_engine.py) into test_output.py.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: 2 people

src/ralphify/_console_emitter.py

@@ -13,7 +13,7 @@
 from rich.console import Console
 
 from ralphify._events import Event, EventType
-from ralphify.engine import format_duration
+from ralphify._output import format_duration
 
 
 class ConsoleEmitter:

src/ralphify/_output.py

@@ -1,4 +1,4 @@
-"""Combine and truncate subprocess output for prompt injection.
+"""Combine, truncate, and format subprocess output.
 
 Output from checks and contexts is capped at :data:`MAX_OUTPUT_LEN`
 characters (5 000) to avoid blowing up the agent's context window.
@@ -30,3 +30,16 @@ def truncate_output(text: str, max_len: int = MAX_OUTPUT_LEN) -> str:
     if len(text) > max_len:
         return text[:max_len] + "\n... (truncated)"
     return text
+
+
+def format_duration(seconds: float) -> str:
+    """Format duration in human-readable form."""
+    if seconds < 60:
+        return f"{seconds:.1f}s"
+    minutes = int(seconds // 60)
+    secs = seconds % 60
+    if minutes < 60:
+        return f"{minutes}m {secs:.0f}s"
+    hours = minutes // 60
+    mins = minutes % 60
+    return f"{hours}h {mins}m"

src/ralphify/engine.py

@@ -17,7 +17,7 @@
 from pathlib import Path
 from typing import NamedTuple
 from ralphify._events import Event, EventEmitter, EventType, NullEmitter
-from ralphify._output import collect_output
+from ralphify._output import collect_output, format_duration
 from ralphify.checks import (
     Check,
     discover_checks,
@@ -123,19 +123,6 @@ def consume_reload_request(self) -> bool:
         return False
 
 
-def format_duration(seconds: float) -> str:
-    """Format duration in human-readable form."""
-    if seconds < 60:
-        return f"{seconds:.1f}s"
-    minutes = int(seconds // 60)
-    secs = seconds % 60
-    if minutes < 60:
-        return f"{minutes}m {secs:.0f}s"
-    hours = minutes // 60
-    mins = minutes % 60
-    return f"{hours}h {mins}m"
-
-
 def _write_log(
     log_path_dir: Path,
     iteration: int,

tests/test_cli.py

@@ -10,7 +10,6 @@
 from ralphify.contexts import Context, ContextResult
 from ralphify.cli import app, CONFIG_FILENAME
 from ralphify._templates import RALPH_TOML_TEMPLATE, PROMPT_TEMPLATE
-from ralphify.engine import format_duration
 
 runner = CliRunner()
 
@@ -529,22 +528,6 @@ def test_timeout_shows_in_header(self, mock_run, tmp_path, monkeypatch):
         assert "5m 0s per iteration" in result.output
 
 
-class TestFormatDuration:
-    def test_seconds(self):
-        assert format_duration(5.3) == "5.3s"
-        assert format_duration(0.1) == "0.1s"
-        assert format_duration(59.9) == "59.9s"
-
-    def test_minutes(self):
-        assert format_duration(60) == "1m 0s"
-        assert format_duration(90.5) == "1m 30s"
-        assert format_duration(3599) == "59m 59s"
-
-    def test_hours(self):
-        assert format_duration(3600) == "1h 0m"
-        assert format_duration(5400) == "1h 30m"
-
-
 def _setup_check(tmp_path, name="ruff-lint", command="ruff check .", enabled=True,
                  body="Fix lint errors."):
     """Helper to create a check directory with CHECK.md."""

tests/test_engine.py

@@ -7,7 +7,7 @@
 from unittest.mock import patch
 
 from ralphify._events import EventType, NullEmitter, QueueEmitter
-from ralphify.engine import RunConfig, RunState, RunStatus, format_duration, run_loop
+from ralphify.engine import RunConfig, RunState, RunStatus, run_loop
 
 _MOCK_SUBPROCESS = "ralphify.engine.subprocess.run"
 
@@ -278,19 +278,3 @@ def stop_later():
 
         assert state.status == RunStatus.STOPPED
         assert mock_run.call_count == 1
-
-
-class TestFormatDuration:
-    def test_seconds(self):
-        assert format_duration(5.3) == "5.3s"
-        assert format_duration(0.1) == "0.1s"
-        assert format_duration(59.9) == "59.9s"
-
-    def test_minutes(self):
-        assert format_duration(60) == "1m 0s"
-        assert format_duration(90.5) == "1m 30s"
-        assert format_duration(3599) == "59m 59s"
-
-    def test_hours(self):
-        assert format_duration(3600) == "1h 0m"
-        assert format_duration(5400) == "1h 30m"

tests/test_output.py

@@ -1,4 +1,4 @@
-from ralphify._output import MAX_OUTPUT_LEN, collect_output, truncate_output
+from ralphify._output import MAX_OUTPUT_LEN, collect_output, format_duration, truncate_output
 
 
 class TestCollectOutput:
@@ -61,3 +61,19 @@ def test_over_limit_truncated(self):
     def test_custom_max_len(self):
         result = truncate_output("hello world", max_len=5)
         assert result == "hello\n... (truncated)"
+
+
+class TestFormatDuration:
+    def test_seconds(self):
+        assert format_duration(5.3) == "5.3s"
+        assert format_duration(0.1) == "0.1s"
+        assert format_duration(59.9) == "59.9s"
+
+    def test_minutes(self):
+        assert format_duration(60) == "1m 0s"
+        assert format_duration(90.5) == "1m 30s"
+        assert format_duration(3599) == "59m 59s"
+
+    def test_hours(self):
+        assert format_duration(3600) == "1h 0m"
+        assert format_duration(5400) == "1h 30m"