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-- Composer version 1.8.5
-- Laravel version 5.8
-- PHP version 7.3.0
-- Fileinfo support ativo
-- GD Support ativo / Version bundled (2.1.0 compatible)
-- Imagick PHP extension não instalada

php composer.phar require intervention/image
Add config/app.php $providers: InterventionImageImageServiceProvider::class
Add config/app.php $alias: 'Image' => InterventionImageFacadesImage::class

$ php artisan vendor:publish --provider="InterventionImageImageServiceProviderLaravel5"

[waservice@web7081 portal]$ php artisan vendor:publish --provider="InterventionImageImageServiceProviderLaravel5"

In ProviderRepository.php line 208:
Class 'InterventionImageImageServiceProvider' not found

[waservice@web7081 ~]$ php composer.phar dump-autoload
Generated autoload files containing 0 classes

[waservice@web7081 ~]$ php composer.phar dump-autoload -o
Generated optimized autoload files containing 156 classes

"require": {
   "php": "^7.1.3",
   "fideloper/proxy": "^4.0",
   "laravel/framework": "5.8.*",
   "laravel/tinker": "^1.0",
   "intervention/image": "dev-master"
},

[waservice@web7081 ~]$ php composer.phar update
Loading composer repositories with package information
Updating dependencies (including require-dev)
Nothing to install or update
Generating autoload files

[waservice@web7081 ~]$ php composer.phar install
Loading composer repositories with package information
Installing dependencies (including require-dev) from lock file
Nothing to install or update
Generating autoload files

[waservice@web7081 ~]$ php composer.phar require intervention/image
Using version ^2.4 for intervention/image
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Nothing to install or update
Generating autoload files