fix(cli): accurate attempt count, elif, stdout on success in exit summary

- m = n + k (exported + failed) instead of total_candidates; avoids
  misleading counts for incremental no-ops and --since last date-filtered
  sessions
- Use elif so mutual exclusion of exit-1/exit-2 is explicit
- Route summary to stdout when k==0 (clean success), stderr when k>0;
  prevents cron monitors treating clean exports as failures
- Add test_since_last_early_return_exits_one_on_failure: validates
  actual exit code 1 without mocking _exit_bulk_export
- Use explicit base/test-project instead of next(base.iterdir())
- Add comment on sys.exit branches and --session doc note in docstring

Author: clean6378-max-it

scripts/export.py

@@ -15,6 +15,7 @@
   0 — all sessions exported successfully (or nothing to export, no errors)
   1 — total failure (no sessions exported; one or more errors)
   2 — partial failure (some sessions exported, some failed)
+  (exit codes apply to bulk export only; --session single-export always exits 0)
 """
 
 import argparse
@@ -400,15 +401,21 @@ def _aggregate_stats(base_dir: str, project_filter: str, fmt: str):
 
 
 def _exit_bulk_export(result: BulkExportResult) -> None:
-    """Map bulk-export counts to process exit code (CLI wrapper only)."""
+    """Map bulk-export counts to process exit code (CLI wrapper only).
+
+    Prints a summary to stderr on any failure, stdout on clean success.
+    Raises SystemExit(1) for total failure, SystemExit(2) for partial.
+    """
     n = result.exported_session_count
-    m = result.total_candidates
     k = result.failure_count
+    # "attempted" = exported + failed; excludes untitled/excluded/mtime-skipped
+    m = n + k
     if n > 0 or k > 0:
-        print(f"Exported {n} of {m} sessions ({k} failed)", file=sys.stderr)
-    if n == 0 and k > 0:
+        dest = sys.stderr if k > 0 else sys.stdout
+        print(f"Exported {n} of {m} sessions ({k} failed)", file=dest)
+    if n == 0 and k > 0:   # total failure
         sys.exit(1)
-    if k > 0:
+    elif k > 0:             # partial failure
         sys.exit(2)
 
 

tests/test_cli_export_exit_codes.py

@@ -57,16 +57,17 @@ def test_cli_export_clean_exits_zero(tmp_path):
     ])
     assert proc.returncode == 0, proc.stderr
     assert list(out_dir.rglob("*.md"))
-    if proc.stderr.strip():
-        assert "failed" not in proc.stderr.lower() or "0 failed" in proc.stderr
+    # Success summary must go to stdout, not stderr
+    assert "Exported" not in proc.stderr
+    assert "Exported 1 of 1 sessions (0 failed)" in proc.stdout
 
 
 def test_cli_export_partial_failure_exits_two(
     tmp_path, monkeypatch, capsys
 ):
     """One session exports; a second fails parse (simulated corrupt file)."""
     base = _seed_base_dir(tmp_path)
-    project_dir = next(base.iterdir())
+    project_dir = base / "test-project"
     bad = project_dir / "session_bad.jsonl"
     bad.write_text('{"type": "user"}\n', encoding="utf-8")
     out_dir = tmp_path / "out"
@@ -134,6 +135,34 @@ def _track_exit(result: BulkExportResult) -> None:
     assert "Exported" not in captured.err
 
 
+def test_since_last_early_return_exits_one_on_failure(
+    tmp_path, monkeypatch, capsys
+):
+    """Since-last early-return with failure_count>0 must produce real exit code 1."""
+    fake_result = BulkExportResult(latest_day=None, failure_count=1)
+
+    monkeypatch.setattr(export, "run_bulk_export", lambda **kwargs: fake_result)
+    monkeypatch.setattr(export, "list_projects", lambda base: [{"name": "p", "path": "/p"}])
+
+    args = types.SimpleNamespace(
+        base_dir=str(tmp_path),
+        out=str(tmp_path / "out"),
+        since="last",
+        no_zip=True,
+        project=None,
+        format="md",
+        session=None,
+        exclude_rules=None,
+    )
+
+    with pytest.raises(SystemExit) as exc_info:
+        export.cmd_export(args)
+
+    assert exc_info.value.code == 1
+    captured = capsys.readouterr()
+    assert "Exported 0 of 1 sessions (1 failed)" in captured.err
+
+
 def test_cli_export_incremental_noop_no_stderr_summary(tmp_path):
     """Second incremental run after state is saved: exit 0, no stderr summary."""
     base = _seed_base_dir(tmp_path)