Add function existence check before opcache_invalidate call (#192)

The code is updated to check for the existence of the
`opcache_invalidate` function before calling it. This change eliminates
potential errors for environments where `opcache_invalidate` might not
be available.

.github/workflows/main.yml

@@ -184,9 +184,8 @@ jobs:
           cd ./build/composer-test
           composer init --no-interaction --name="test/test"
           composer require jbzoo/csv-blueprint
-          ./vendor/bin/csv-blueprint || true
-          ./vendor/bin/csv-blueprint $CMD_VALIDATE $VALID_TEST || true
-          ./vendor/bin/csv-blueprint $CMD_VALIDATE $INVALID_TEST || true
+          ./vendor/bin/csv-blueprint
+          ./vendor/bin/csv-blueprint validate-csv --ansi -vvv --csv="../../tests/fixtures/batch/*.csv" --schema="../../tests/schemas/demo_valid.yml"
 
 
   verify-phar-binary:

src/Commands/AbstractValidate.php

@@ -139,7 +139,7 @@ protected function findFiles(string $option, bool $throwException = true): array
         $filenames = \array_values(Utils::findFiles($patterns));
 
         // Hackish. Clear cache for schema files because we have aggressive opcode caching.
-        if ($option === 'schema') {
+        if ($option === 'schema' && \function_exists('opcache_invalidate')) {
             foreach ($filenames as $filename) {
                 \opcache_invalidate((string)$filename->getRealPath(), true);
             }