fix: the check names files it cannot supply

--check counted the required files the list leaves out and named none, then said all files were up to date. A Recalbox user asking why Caesar III would not start learned nothing, though the list names c3.555. The count line no longer calls a file not found unsafe.

install.ps1

@@ -8,7 +8,7 @@ param(
 
 $ErrorActionPreference = "Stop"
 $defaultInstallUrl = "https://raw.githubusercontent.com/Abdess/retrobios/main/install.py"
-$defaultInstallSha256 = "bc7e519f5bc6dbbc062a0ac29558dbe6862299e6d511b97c048f52ce2db5fba3"
+$defaultInstallSha256 = "26f2b2fc61c828de3eceec4cc6ba90d10801b3c97a88531adf9b8307a3866e2e"
 $maximumInstallerBytes = 2MB
 $installerExit = 0
 $installer = if ($PSScriptRoot) { Join-Path $PSScriptRoot "install.py" } else { $null }

install.py

@@ -2816,6 +2816,22 @@ def _omission_lines(count: int, entries: list[dict]) -> list[str]:
     return lines
 
 
+def _absent_required(omitted: list[dict], bios_path: Path) -> list[str]:
+    """Required files the manifest leaves out that the user has not placed."""
+    names = set()
+    for entry in omitted:
+        dest = entry.get("dest") or entry.get("name", "")
+        if not entry.get("required", True) or not dest:
+            continue
+        try:
+            placed = _destination_path(bios_path, dest).is_file()
+        except ValueError:
+            placed = False  # a path climbing out of the folder is never one we read
+        if not placed:
+            names.add(dest)
+    return sorted(names)
+
+
 # Asked before, in an interactive run: past this size a download is worth a
 # second thought, and --system, --core or --region can make it smaller.
 CONFIRM_FROM_BYTES = 1024 * 1024 * 1024
@@ -3960,8 +3976,8 @@ def _install(args: argparse.Namespace, real_stdout: TextIO) -> None:
                 for reason, count in sorted(reasons.items())
             )
             print(
-                f"  Safety notice: {len(omitted_files)} unavailable or unsafe "
-                f"entries omitted ({required_omitted} required; {reason_summary})."
+                f"  Not installable: {_plural(len(omitted_files), 'file')} "
+                f"({required_omitted} required, {reason_summary})."
             )
             total_omitted += len(omitted_files)
             omitted_seen.extend(omitted_files)
@@ -4016,6 +4032,14 @@ def _install(args: argparse.Namespace, real_stdout: TextIO) -> None:
                 check_pending += len(to_download)
             else:
                 print("\n  All files up to date.")
+            absent = _absent_required(omitted_files, bios_path)
+            if absent:
+                # The collection cannot supply these, so they leave the exit
+                # code alone, but a user asking why a game will not start
+                # needs their names.
+                print(f"  Not in the collection and absent here, needed to start "
+                      f"an emulator: {', '.join(absent[:10])}"
+                      + (f" and {len(absent) - 10} more" if len(absent) > 10 else ""))
             for entry in data_dirs:
                 _root, needed, present = data_directory_state(entry, bios_path)
                 if needed:

install.sh

@@ -18,7 +18,7 @@ esac
 TEMP_INSTALLER=""
 TEMP_DIRECTORY=""
 DEFAULT_INSTALL_URL="https://raw.githubusercontent.com/Abdess/retrobios/main/install.py"
-DEFAULT_INSTALL_SHA256="bc7e519f5bc6dbbc062a0ac29558dbe6862299e6d511b97c048f52ce2db5fba3"
+DEFAULT_INSTALL_SHA256="26f2b2fc61c828de3eceec4cc6ba90d10801b3c97a88531adf9b8307a3866e2e"
 MAX_INSTALLER_BYTES=2097152
 
 cleanup() {

tests/test_install.py

@@ -2808,6 +2808,50 @@ class AResumedCopyIsNotSpeed(unittest.TestCase):
 
 
 
+class ACheckNamesWhatTheCollectionLacks(unittest.TestCase):
+    """--check counted the required files the manifest leaves out and named
+    none, then said all files were up to date: on Recalbox, c3.555 stayed
+    unnamed for a user asking why Caesar III would not start."""
+
+    def test_recalbox_caesar3(self):
+        import shutil  # noqa: PLC0415
+        import subprocess  # noqa: PLC0415
+
+        manifest = json.loads((REPO_ROOT / "install" / "recalbox.json").read_text())
+        lacking = sorted(
+            e["dest"] for e in manifest.get("omitted_files", [])
+            if e.get("required") and e.get("system") == "caesar3"
+        )
+        if not lacking:
+            self.skipTest("the Recalbox manifest omits no required caesar3 file")
+        handler = functools.partial(
+            http.server.SimpleHTTPRequestHandler, directory=str(REPO_ROOT)
+        )
+        handler.log_message = lambda *args: None
+        httpd = http.server.ThreadingHTTPServer(("127.0.0.1", 0), handler)
+        threading.Thread(target=httpd.serve_forever, daemon=True).start()
+        self.addCleanup(httpd.server_close)
+        self.addCleanup(httpd.shutdown)
+        (REPO_ROOT / "tmp").mkdir(exist_ok=True)
+        home = Path(tempfile.mkdtemp(dir=str(REPO_ROOT / "tmp")))
+        self.addCleanup(shutil.rmtree, home, True)
+        env = {
+            **os.environ, "HOME": str(home), "RETROBIOS_OS": "linux",
+            "RETROBIOS_BASE_URL": f"http://127.0.0.1:{httpd.server_address[1]}",
+        }
+        proc = subprocess.run(
+            [sys.executable, "-I", "install.py", "--platform", "recalbox",
+             "--no-input", "--dest", str(home / "bios"), "--check"],
+            cwd=REPO_ROOT, env=env, capture_output=True, text=True, timeout=300,
+            check=False,
+        )
+        self.assertNotIn("Traceback", proc.stderr)
+        for dest in lacking:
+            self.assertIn(dest, proc.stdout)
+        self.assertNotIn("unsafe", proc.stdout)
+
+
+
 class ThePagesQuoteTheBootstrapsOwnWords(unittest.TestCase):
     """The installer page and the FAQ quoted "install.py SHA-256 mismatch",
     a message the bootstraps no longer print."""

wiki/installer.md

@@ -111,8 +111,10 @@ Checking existing files...
 ```
 
 When the manifest leaves entries out (a file the collection cannot supply, or
-one that failed a safety check), a `Safety notice:` line under the index count
-says how many and why.
+one that failed its hash check), a `Not installable:` line under the index count
+says how many and why. `--check` also names the required ones missing from the
+folder. They do not change its exit code, since no run of the installer can
+fetch them.
 
 ## Choosing what to install