fix: name a sign-in page sent for the file list

install.ps1

@@ -16,7 +16,7 @@
     # and Invoke-WebRequest throws on a cut transfer before the hash is read:
     # the site's build rewrites this line there (scripts/sitebootstrap.py).
     $mismatchAdvice = "The download was most likely cut short: try again. Within minutes of an update of this project the two files can come from caches of different ages. Waiting five minutes settles that."
-    $defaultInstallSha256 = "ca1c3c0d721787ee0fd9ab750839893d64f9313885dde6c1f88c5174d4281ce0"
+    $defaultInstallSha256 = "5255181d018ce7020a619c6a31419da0dde862626bc57347cd0299a099e64f11"
     $maximumInstallerBytes = 2MB
     $installerExit = 0
     $installer = if ($PSScriptRoot) { Join-Path $PSScriptRoot "install.py" } else { $null }

install.py

@@ -4056,9 +4056,20 @@ def fetch_manifest(plat: str) -> dict:
     try:
         return _validate_manifest(_fetch_json(url, MAX_MANIFEST_BYTES, "file list"), plat)
     except ValueError as exc:
+        words = f"the file list is not valid: {exc}"
+        if isinstance(exc.__cause__, (json.JSONDecodeError, UnicodeDecodeError)):
+            # The parser's "Expecting value: line 1 column 1" told no one
+            # anything, where the full screen names the usual cause.
+            words = ("what arrived is not a file list: a Wi-Fi sign-in page or a cut "
+                     "download looks like this")
         EVENTS.emit("error", stage="manifest", reason="invalid", platform=plat,
-                    message=f"the file list is not valid: {exc}")
-        print(f"  The file list for {plat} is not valid: {exc}", file=sys.stderr)
+                    message=words)
+        print(f"  For {display_name(plat)}, {words}.", file=sys.stderr)
+        if words.startswith("what arrived"):
+            for line in _address_lines(url):
+                print(line, file=sys.stderr)
+            print("  Check the connection (sign in to the Wi-Fi if it asks), then run the "
+                  "same command again.", file=sys.stderr)
         sys.exit(1)
     except urllib.error.HTTPError as exc:
         EVENTS.emit(

install.sh

@@ -23,7 +23,7 @@ DEFAULT_INSTALL_URL="https://raw.githubusercontent.com/Abdess/retrobios/main/ins
 # curl or wget stop on a cut transfer before the hash is read: the site's
 # build rewrites this line there (scripts/sitebootstrap.py).
 MISMATCH_ADVICE="The download was most likely cut short: try again. Within minutes of an update of this project the two files can come from caches of different ages. Waiting five minutes settles that."
-DEFAULT_INSTALL_SHA256="ca1c3c0d721787ee0fd9ab750839893d64f9313885dde6c1f88c5174d4281ce0"
+DEFAULT_INSTALL_SHA256="5255181d018ce7020a619c6a31419da0dde862626bc57347cd0299a099e64f11"
 MAX_INSTALLER_BYTES=2097152
 
 cleanup() {

install/launchers/index.json

@@ -27,8 +27,8 @@
         {
           "dest": "roms/ports/retrobios/install.py",
           "repo_path": "install.py",
-          "size": 1083967,
-          "sha256": "ca1c3c0d721787ee0fd9ab750839893d64f9313885dde6c1f88c5174d4281ce0",
+          "size": 1084625,
+          "sha256": "5255181d018ce7020a619c6a31419da0dde862626bc57347cd0299a099e64f11",
           "executable": false
         },
         {
@@ -71,8 +71,8 @@
     "muos": {
       "archive": {
         "dest": "ARCHIVE/RetroBIOS.muxapp",
-        "size": 1137594,
-        "sha256": "433caee0f48148c8c25122e3cfa4a6d4577160a2b4ddcf2267415ebd21beb843"
+        "size": 1138252,
+        "sha256": "bc75188e7d115aa35066fba281deb2bec5ce07553ebdbe2d8444d0dbdfc5d41d"
       },
       "members": [
         {
@@ -92,8 +92,8 @@
         {
           "name": "RetroBIOS/install.py",
           "repo_path": "install.py",
-          "size": 1083967,
-          "sha256": "ca1c3c0d721787ee0fd9ab750839893d64f9313885dde6c1f88c5174d4281ce0",
+          "size": 1084625,
+          "sha256": "5255181d018ce7020a619c6a31419da0dde862626bc57347cd0299a099e64f11",
           "executable": false
         },
         {
@@ -166,8 +166,8 @@
         {
           "dest": ".config/modules/retrobios/install.py",
           "repo_path": "install.py",
-          "size": 1083967,
-          "sha256": "ca1c3c0d721787ee0fd9ab750839893d64f9313885dde6c1f88c5174d4281ce0",
+          "size": 1084625,
+          "sha256": "5255181d018ce7020a619c6a31419da0dde862626bc57347cd0299a099e64f11",
           "executable": false
         },
         {

tests/test_install.py

@@ -2404,6 +2404,22 @@ class FileListsAreRetried(unittest.TestCase):
         self.assertIs(result, missing)
         self.assertEqual(len(calls), 1)
 
+    def test_a_sign_in_page_is_named(self):
+        """A Wi-Fi sign-in page read as "invalid file list: Expecting value:
+        line 1 column 1 (char 0)", with no cause and no next step."""
+        page = io.BytesIO(b"<html>Sign in to Hotel WiFi</html>")
+        page.headers = {}
+        err = io.StringIO()
+        with unittest.mock.patch.object(
+                install.urllib.request, "urlopen",
+                lambda url, timeout=None: contextlib.nullcontext(page)), \
+                contextlib.redirect_stderr(err), self.assertRaises(SystemExit):
+            install.fetch_manifest("retroarch")
+        said = err.getvalue()
+        self.assertIn("a Wi-Fi sign-in page or a cut download looks like this", said)
+        self.assertIn("run the same command again", said)
+        self.assertNotIn("Expecting value", said)
+
     def test_three_failures_end_with_advice(self):
         import urllib.error