bug symfony#58983 [Translation] [Bridge][Lokalise] Fix empty keys array in PUT, DELETE requests causing Lokalise API error (DominicLuidold)

This PR was squashed before being merged into the 5.4 branch.

Discussion
----------

[Translation] [Bridge][Lokalise] Fix empty keys array in PUT, DELETE requests causing Lokalise API error

| Q             | A
| ------------- | ---
| Branch?       | 5.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        | /
| License       | MIT

This PR fixes two cases where an empty `keys` array is passed to a `PUT`/`DELETE` request, resulting in a Lokalise API error.

The empty arrays are the result of a `Symfony\Component\Translation\TranslatorBag` containing one or more `Symfony\Component\Translation\MessageCatalogue` _without any_ messages getting passed into the `Symfony\Component\Translation\Bridge\Lokalise\LokaliseProvider` (which is expected behaviour, see [here](https://github.com/symfony/symfony/blob/7.3/src/Symfony/Component/Translation/Command/TranslationPushCommand.php#L153) and below).

This is the case if either
* `bin/console translation:push lokalise`
* `bin/console translation:push lokalise --delete-missing`

is called when both the local translations as well as the translations on Lokalise match 1:1 for a given translation domain.

This will fix the following erros that might be observed while running the mentioned commands:

<details>
<summary>Before/after for <code>translation:push lokalise</code></summary>

**Before:**
```console
$ bin/console translation:push lokalise --domains=validators

ERROR     [app] Unable to get keys ids from Lokalise: "{"error":{"message":"`filter_filenames` parameter has invalid values","code":400}}".

 [OK] All local translations has been sent to "lokalise" (for "de, en, fr, it" locale(s), and "validators"
      domain(s)).
```

**After:**
```console
$ bin/console translation:push lokalise --domains=validators

 [OK] All local translations has been sent to "lokalise" (for "de, en, fr, it" locale(s), and "validators"
      domain(s)).
```

</details>

<details>
<summary>Before/after for <code>translation:push lokalise --delete-missing</code></summary>

**Before:**
```console
$ bin/console translation:push lokalise --domains=validators --delete-missing

In LokaliseProvider.php line 135:

  Unable to delete keys from Lokalise: "{"error":{"message":"`keys` parameter is not valid","code":400}}".

translation:push [--force] [--delete-missing] [--domains [DOMAINS]] [--locales [LOCALES]] [--] [<provider>]
```

**After:**
```console
$ bin/console translation:push lokalise --domains=validators --delete-missing

 [OK] Missing translations on "lokalise" has been deleted (for "de, en, fr, it" locale(s), and "validators"
      domain(s)).

 [OK] All local translations has been sent to "lokalise" (for "de, en, fr, it" locale(s), and "validators"
      domain(s)).
```

</details>

Commits
-------

2e51808 [Translation] [Bridge][Lokalise] Fix empty keys array in PUT, DELETE requests causing Lokalise API error

Author: nicolas-grekas

src/Symfony/Component/Translation/Bridge/Lokalise/LokaliseProvider.php

@@ -129,6 +129,10 @@ public function delete(TranslatorBagInterface $translatorBag): void
             $keysIds += $this->getKeysIds($keysToDelete, $domain);
         }
 
+        if (!$keysIds) {
+            return;
+        }
+
         $response = $this->client->request('DELETE', 'keys', [
             'json' => ['keys' => array_values($keysIds)],
         ]);
@@ -261,6 +265,10 @@ private function updateTranslations(array $keysByDomain, TranslatorBagInterface
             }
         }
 
+        if (!$keysToUpdate) {
+            return;
+        }
+
         $response = $this->client->request('PUT', 'keys', [
             'json' => ['keys' => $keysToUpdate],
         ]);

src/Symfony/Component/Translation/Bridge/Lokalise/Tests/LokaliseProviderTest.php

@@ -249,6 +249,56 @@ public function testCompleteWriteProcess()
         $this->assertTrue($updateProcessed, 'Translations update was not called.');
     }
 
+    public function testUpdateProcessWhenLocalTranslationsMatchLokaliseTranslations()
+    {
+        $getLanguagesResponse = function (string $method, string $url): ResponseInterface {
+            $this->assertSame('GET', $method);
+            $this->assertSame('https://api.lokalise.com/api2/projects/PROJECT_ID/languages', $url);
+
+            return new MockResponse(json_encode([
+                'languages' => [
+                    ['lang_iso' => 'en'],
+                    ['lang_iso' => 'fr'],
+                ],
+            ]));
+        };
+
+        $failOnPutRequest = function (string $method, string $url, array $options = []): void {
+            $this->assertSame('PUT', $method);
+            $this->assertSame('https://api.lokalise.com/api2/projects/PROJECT_ID/keys', $url);
+            $this->assertSame(json_encode(['keys' => []]), $options['body']);
+
+            $this->fail('PUT request is invalid: an empty `keys` array was provided, resulting in a Lokalise API error');
+        };
+
+        $mockHttpClient = (new MockHttpClient([
+            $getLanguagesResponse,
+            $failOnPutRequest,
+        ]))->withOptions([
+            'base_uri' => 'https://api.lokalise.com/api2/projects/PROJECT_ID/',
+            'headers' => ['X-Api-Token' => 'API_KEY'],
+        ]);
+
+        $provider = self::createProvider(
+            $mockHttpClient,
+            $this->getLoader(),
+            $this->getLogger(),
+            $this->getDefaultLocale(),
+            'api.lokalise.com'
+        );
+
+        // TranslatorBag with catalogues that do not store any message to mimic the behaviour of
+        // Symfony\Component\Translation\Command\TranslationPushCommand when local translations and Lokalise
+        // translations match without any changes in both translation sets
+        $translatorBag = new TranslatorBag();
+        $translatorBag->addCatalogue(new MessageCatalogue('en', []));
+        $translatorBag->addCatalogue(new MessageCatalogue('fr', []));
+
+        $provider->write($translatorBag);
+
+        $this->assertSame(1, $mockHttpClient->getRequestsCount());
+    }
+
     public function testWriteGetLanguageServerError()
     {
         $getLanguagesResponse = function (string $method, string $url, array $options = []): ResponseInterface {
@@ -721,6 +771,38 @@ public function testDeleteProcess()
         $provider->delete($translatorBag);
     }
 
+    public function testDeleteProcessWhenLocalTranslationsMatchLokaliseTranslations()
+    {
+        $failOnDeleteRequest = function (string $method, string $url, array $options = []): void {
+            $this->assertSame('DELETE', $method);
+            $this->assertSame('https://api.lokalise.com/api2/projects/PROJECT_ID/keys', $url);
+            $this->assertSame(json_encode(['keys' => []]), $options['body']);
+
+            $this->fail('DELETE request is invalid: an empty `keys` array was provided, resulting in a Lokalise API error');
+        };
+
+        // TranslatorBag with catalogues that do not store any message to mimic the behaviour of
+        // Symfony\Component\Translation\Command\TranslationPushCommand when local translations and Lokalise
+        // translations match without any changes in both translation sets
+        $translatorBag = new TranslatorBag();
+        $translatorBag->addCatalogue(new MessageCatalogue('en', []));
+        $translatorBag->addCatalogue(new MessageCatalogue('fr', []));
+
+        $mockHttpClient = new MockHttpClient([$failOnDeleteRequest], 'https://api.lokalise.com/api2/projects/PROJECT_ID/');
+
+        $provider = self::createProvider(
+            $mockHttpClient,
+            $this->getLoader(),
+            $this->getLogger(),
+            $this->getDefaultLocale(),
+            'api.lokalise.com'
+        );
+
+        $provider->delete($translatorBag);
+
+        $this->assertSame(0, $mockHttpClient->getRequestsCount());
+    }
+
     public static function getResponsesForOneLocaleAndOneDomain(): \Generator
     {
         $arrayLoader = new ArrayLoader();