feat(fusion_accounting_reports): fusion.report.engine 5-method API

The engine orchestrator. compute_pnl, compute_balance_sheet,
compute_trial_balance, compute_gl, drill_down. All controllers,
wizards, AI tools must route through these methods; no direct
SQL aggregation from anywhere else.

Internal pipeline: validate -> fetch hierarchy -> SQL aggregate
-> resolve line_specs -> optional comparison + anomaly. Uses raw
SQL for the per-account aggregate (the perf-critical step), ORM
for everything else.

Per-company report lookup with global fallback (company_id desc
nulls last). Balance sheet uses 1970 epoch as date_from for
cumulative-since-inception semantics.

7 new tests, 42 total passing.

Made-with: Cursor

fusion_accounting_reports/tests/__init__.py

@@ -3,3 +3,4 @@ from . import test_currency_conversion
 from . import test_fusion_report
 from . import test_line_resolver
 from . import test_drill_down_resolver
+from . import test_fusion_report_engine

fusion_accounting_reports/tests/test_fusion_report_engine.py

@@ -0,0 +1,109 @@
+"""Tests for fusion.report.engine AbstractModel."""
+
+from datetime import date
+
+from odoo.exceptions import ValidationError
+from odoo.tests.common import TransactionCase, tagged
+from odoo.addons.fusion_accounting_reports.services.date_periods import Period
+
+
+@tagged('post_install', '-at_install')
+class TestFusionReportEngine(TransactionCase):
+
+    def setUp(self):
+        super().setUp()
+        self.pnl_report = self.env['fusion.report'].create({
+            'name': 'Test P&L Engine',
+            'code': 'test_pnl_engine',
+            'report_type': 'pnl',
+            'line_specs': [
+                {'label': 'Revenue', 'account_type_prefix': 'income_', 'sign': 1},
+                {'label': 'Expenses', 'account_type_prefix': 'expense_', 'sign': -1},
+                {'label': 'Net Profit', 'compute': 'subtotal', 'above': 2},
+            ],
+            'company_id': self.env.company.id,
+        })
+
+    def test_engine_model_exists(self):
+        self.assertIn('fusion.report.engine', self.env.registry)
+
+    def test_compute_pnl_returns_dict_with_rows(self):
+        period = Period(date(2026, 1, 1), date(2026, 12, 31), 'Test 2026')
+        result = self.env['fusion.report.engine'].compute_pnl(
+            period, company_id=self.env.company.id,
+        )
+        self.assertIn('rows', result)
+        self.assertIn('report_type', result)
+        self.assertEqual(result['report_type'], 'pnl')
+
+    def test_compute_balance_sheet(self):
+        self.env['fusion.report'].create({
+            'name': 'Test BS',
+            'code': 'test_bs_engine',
+            'report_type': 'balance_sheet',
+            'line_specs': [
+                {'label': 'Assets', 'account_type_prefix': 'asset_', 'sign': 1},
+            ],
+            'company_id': self.env.company.id,
+        })
+        result = self.env['fusion.report.engine'].compute_balance_sheet(
+            date(2026, 4, 19), company_id=self.env.company.id,
+        )
+        self.assertEqual(result['report_type'], 'balance_sheet')
+        self.assertEqual(result['period']['date_to'], '2026-04-19')
+
+    def test_compute_trial_balance(self):
+        self.env['fusion.report'].create({
+            'name': 'Test TB',
+            'code': 'test_tb_engine',
+            'report_type': 'trial_balance',
+            'line_specs': [],
+            'company_id': self.env.company.id,
+        })
+        period = Period(date(2026, 1, 1), date(2026, 12, 31), 'Test 2026')
+        result = self.env['fusion.report.engine'].compute_trial_balance(
+            period, company_id=self.env.company.id,
+        )
+        self.assertEqual(result['report_type'], 'trial_balance')
+
+    def test_compute_pnl_with_comparison(self):
+        period = Period(date(2026, 1, 1), date(2026, 12, 31), 'Test 2026')
+        result = self.env['fusion.report.engine'].compute_pnl(
+            period,
+            comparison='previous_year',
+            company_id=self.env.company.id,
+        )
+        self.assertIsNotNone(result.get('comparison_period'))
+        self.assertEqual(result['comparison_period']['date_to'], '2025-12-31')
+
+    def test_drill_down_returns_list(self):
+        line = self.env['account.move.line'].search([
+            ('parent_state', '=', 'posted'),
+        ], limit=1)
+        if not line:
+            self.skipTest("No posted lines in DB")
+        period = Period(line.date, line.date, 'Single day')
+        rows = self.env['fusion.report.engine'].drill_down(
+            account_id=line.account_id.id,
+            period=period,
+            company_id=line.company_id.id,
+        )
+        self.assertIsInstance(rows, list)
+
+    def test_no_report_raises_validation_error(self):
+        period = Period(date(2026, 1, 1), date(2026, 12, 31), 'Test 2026')
+        # Inactivate any pre-existing GL definitions so the lookup
+        # fails for this test, then restore them after.
+        existing = self.env['fusion.report'].search(
+            [('report_type', '=', 'general_ledger')]
+        )
+        prior_active = {r.id: r.active for r in existing}
+        existing.write({'active': False})
+        try:
+            with self.assertRaises(ValidationError):
+                self.env['fusion.report.engine'].compute_gl(
+                    period, company_id=self.env.company.id,
+                )
+        finally:
+            for r in existing:
+                r.active = prior_active.get(r.id, True)