fix(salary): distinguish absent indexes from suppression (#584)

* fix(salary): distinguish absent indexes from suppression

* docs(changelog): record fix for #584

tests/test_salary_count_only_cli.py

@@ -0,0 +1,71 @@
+"""Count-only workbook categories do not imply a suppressed salary index."""
+import json
+import shutil
+import subprocess
+import sys
+import unittest
+from pathlib import Path
+from tempfile import TemporaryDirectory
+
+try:
+    import openpyxl
+except ImportError:
+    openpyxl = None
+
+REPO = Path(__file__).resolve().parent.parent
+
+
+class CountOnlySalaryCLI(unittest.TestCase):
+    def setUp(self):
+        directory = TemporaryDirectory()
+        self.addCleanup(directory.cleanup)
+        self.root = Path(directory.name)
+        shutil.copyfile(REPO / "salary_lookup.py", self.root / "salary_lookup.py")
+
+    def lookup(self):
+        result = subprocess.run(
+            [sys.executable, str(self.root / "salary_lookup.py"), "Acme Corp"],
+            capture_output=True, text=True, encoding="utf-8",
+        )
+        self.assertEqual(result.returncode, 0, result.stderr)
+        return result.stdout
+
+    def convert(self, headers, row):
+        workbook = self.root / "salary.xlsx"
+        book = openpyxl.Workbook()
+        try:
+            book.active.append(headers)
+            book.active.append(row)
+            book.save(workbook)
+        finally:
+            book.close()
+        result = subprocess.run(
+            [sys.executable, str(REPO / "tools/convert_salary_excel.py"), str(workbook),
+             "--output", str(self.root / "salary_data.json")],
+            capture_output=True, text=True, encoding="utf-8",
+        )
+        self.assertEqual(result.returncode, 0, result.stderr)
+
+    @unittest.skipUnless(openpyxl, "requires optional openpyxl (installed in CI)")
+    def test_count_only_workbook_does_not_claim_privacy_suppression(self):
+        self.convert(["Company", "Count"], ["Acme Corp", 500])
+        output = self.lookup()
+        self.assertRegex(output, r"Count\s+500\s+-")
+        self.assertNotIn("N/A", output)
+        self.assertNotIn("privacy", output)
+
+    @unittest.skipUnless(openpyxl, "requires optional openpyxl (installed in CI)")
+    def test_paired_numeric_index_control(self):
+        self.convert(["Company", "Count", "Index"], ["Acme Corp", 500, 108.5])
+        output = self.lookup()
+        self.assertIn("108.5", output)
+        self.assertIn("+8.5%", output)
+        self.assertNotIn("privacy", output)
+
+    def test_explicit_null_index_keeps_the_existing_suppression_marker(self):
+        (self.root / "salary_data.json").write_text(json.dumps({"companies": [{
+            "company": "Acme Corp", "categories": {"small_team": {"count": 3, "index": None}},
+        }]}), encoding="utf-8")
+        output = self.lookup()
+        self.assertIn("N/A*", output)
+        self.assertIn("Too few employees to publish (privacy)", output)