Find the files a real upgrade leaves behind

"Scan existing files" sat disabled on an installation with a library of
144 of them, and the hourly backfill would have found none either. Both
looked for `scan_note = 'before_scanning'`, and no file on any upgraded
installation carries it: the migration gives `scan_status` its default
and writes no note, and the v1 import inserts rows the same way. The
feature was inert on exactly the libraries it exists for.

A file with no reason beside its "not scanned" is now what it plainly
is — one nothing has ever looked at — through File::neverScanned(),
which the backfill, the counts and the badge all ask. Reported as
"Uploaded before virus scanning was switched on" rather than as a bare
"Not scanned", which is the one badge somebody would have had to come
and ask about.

Found on the real screen, not by a test. The tests now cover the shape
an upgrade actually produces.

app/Modules/Files/Console/ScanFilesCommand.php

@@ -57,13 +57,7 @@ class ScanFilesCommand extends Command
             // run, since that is how often this command runs.
             $limit = $config->existingScanRatePerMinute() * 60;
 
-            $old = $this->dispatchFor(
-                File::query()
-                    ->where('scan_status', ScanStatus::NotScanned)
-                    ->where('scan_note', NotScannedReason::BeforeScanning->value),
-                $limit,
-                rescan: true,
-            );
+            $old = $this->dispatchFor(File::query()->neverScanned(), $limit, rescan: true);
 
             $this->info("Queued {$old} file(s) that had never been scanned.");
         }

app/Modules/Files/Http/Controllers/FoldersController.php

@@ -220,7 +220,12 @@ class FoldersController extends Controller
             return null;
         }
 
-        $note = $file->scan_note;
+        // A file from before the scanner existed carries no reason — see
+        // File::scopeNeverScanned — and "Not scanned" with no explanation
+        // is the one badge somebody would have to come and ask about.
+        $note = $file->scan_note ?? ($file->scan_status === ScanStatus::NotScanned
+            ? NotScannedReason::BeforeScanning->value
+            : null);
 
         return [
             'status' => $file->scan_status->value,

app/Modules/Files/Http/Controllers/VirusScanningSettingsController.php

@@ -211,10 +211,7 @@ class VirusScanningSettingsController extends Controller
                 ScanStatus::Infected->value,
                 ScanStatus::UnscannableBlocked->value,
             ])->count(),
-            'never_scanned' => File::query()
-                ->where('scan_status', ScanStatus::NotScanned)
-                ->where('scan_note', NotScannedReason::BeforeScanning->value)
-                ->count(),
+            'never_scanned' => File::query()->neverScanned()->count(),
             'let_through' => File::query()
                 ->where('scan_status', ScanStatus::NotScanned)
                 ->whereIn('scan_note', [

app/Modules/Files/Models/File.php

@@ -10,6 +10,7 @@ use App\Modules\Audit\ActivityLog;
 use App\Modules\Files\Access\SharingIdentity;
 use App\Modules\Files\DownloadLimitScope;
 use App\Modules\Files\FileDiskCleanup;
+use App\Modules\Files\Scanning\NotScannedReason;
 use App\Modules\Files\Scanning\ScanStatus;
 use App\Modules\Files\Versions\FileVersions;
 use App\Modules\Groups\Models\Group;
@@ -311,6 +312,27 @@ class File extends Model
         });
     }
 
+    /**
+     * Files nothing has ever looked at.
+     *
+     * Two ways to be one, and the second is the common one: a file stored
+     * while scanning was off carries the reason, and a file that predates
+     * the scanner entirely carries none at all — the migration gives the
+     * column its default and writes no note, and the v1 import inserts
+     * rows the same way. Reading only the reason missed every file on
+     * every real installation, which is exactly the set "Scan existing
+     * files" exists for.
+     *
+     * @param  Builder<File>  $query
+     */
+    public function scopeNeverScanned(Builder $query): void
+    {
+        $query->where('scan_status', ScanStatus::NotScanned)
+            ->where(fn (Builder $inner) => $inner
+                ->whereNull('scan_note')
+                ->orWhere('scan_note', NotScannedReason::BeforeScanning->value));
+    }
+
     /**
      * @param  Builder<File>  $query
      */

tests/Feature/Files/VirusScanningSettingsTest.php

@@ -35,6 +35,11 @@ beforeEach(function () {
 test('the screen shows what is configured and what is outstanding', function () {
     File::factory()->create(['scan_status' => ScanStatus::NotScanned, 'scan_note' => NotScannedReason::ScannerUnavailable->value]);
     File::factory()->create(['scan_status' => ScanStatus::NotScanned, 'scan_note' => NotScannedReason::BeforeScanning->value]);
+    // The shape every upgraded installation is actually in: the status
+    // from the column default, and no reason beside it. Counted, or the
+    // "Scan existing files" button sits disabled on a library of
+    // thousands.
+    File::factory()->create(['scan_status' => ScanStatus::NotScanned, 'scan_note' => null]);
     File::factory()->create(['scan_status' => ScanStatus::Infected, 'scan_note' => 'X']);
 
     $this->actingAs($this->admin)->get('/system/settings/virus-scanning')->assertInertia(
@@ -42,7 +47,7 @@ test('the screen shows what is configured and what is outstanding', function ()
             ->component('system/settings/virus-scanning')
             ->where('managed', false)
             ->where('counts.let_through', 1)
-            ->where('counts.never_scanned', 1)
+            ->where('counts.never_scanned', 2)
             ->where('counts.quarantined', 1),
     );
 });

tests/Feature/Files/VirusScanningTest.php

@@ -441,3 +441,38 @@ test('the activity log names the file it quarantined', function () {
     expect($line)->toContain('Contrato firmado')
         ->toContain('Eicar-Test-Signature');
 });
+
+test('a library from before the scanner is what "scan existing files" actually finds', function () {
+    // The migration gives the column its default and writes no reason, so
+    // every file on every upgraded installation has scan_note = null. A
+    // backfill that looked for the reason found none of them — the whole
+    // feature was inert on exactly the libraries it exists for.
+    $old = File::factory()->create(['scan_status' => ScanStatus::NotScanned, 'scan_note' => null]);
+    $stated = File::factory()->create([
+        'scan_status' => ScanStatus::NotScanned,
+        'scan_note' => NotScannedReason::BeforeScanning->value,
+    ]);
+    $letThrough = File::factory()->create([
+        'scan_status' => ScanStatus::NotScanned,
+        'scan_note' => NotScannedReason::ScannerUnavailable->value,
+    ]);
+
+    $found = File::query()->neverScanned()->pluck('id')->all();
+
+    expect($found)->toContain($old->id)
+        ->toContain($stated->id)
+        // Not this one: it was offered to a scanner that could not answer,
+        // and the hourly sweep already re-scans those.
+        ->not->toContain($letThrough->id);
+});
+
+test('the backfill queues those files', function () {
+    fakeScanner(ScanVerdict::clean());
+    $old = scannableFile(['scan_status' => ScanStatus::NotScanned, 'scan_note' => null]);
+
+    Illuminate\Support\Facades\Queue::fake();
+
+    $this->artisan('projectsend:scan-files', ['--existing' => true])->assertSuccessful();
+
+    Illuminate\Support\Facades\Queue::assertPushed(ScanFileJob::class, fn (ScanFileJob $job): bool => $job->fileId === $old->id);
+});