Running phpcs --standard=Drupal,DrupalPractice --extensions=php,module,inc,install,test,profile,theme,css,info,txt,md,yml,twig shows the following warnings/errors, which should be fixed.
FILE: ./countries_field.info.yml
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FOUND 0 ERRORS AND 1 WARNING AFFECTING 1 LINE
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1 | WARNING | "core_version_requirement" property is missing in the
| | info.yml file
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FILE: ./src/Continents.php
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FOUND 1 ERROR AND 5 WARNINGS AFFECTING 5 LINES
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9 | WARNING | The class short comment should describe what the
| | class does and not simply repeat the class name
23 | WARNING | \Drupal calls should be avoided in classes, use
| | dependency injection instead
51 | WARNING | t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait
| | and $this->t() instead
51 | WARNING | Only string literals should be passed to t() where
| | possible
96 | WARNING | \Drupal calls should be avoided in classes, use
| | dependency injection instead
105 | ERROR | Public method name "Continents::getDBStructure" is
| | not in lowerCamel format
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FILE: ./src/Controller/CountryController.php
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FOUND 0 ERRORS AND 1 WARNING AFFECTING 1 LINE
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11 | WARNING | The class short comment should describe what the
| | class does and not simply repeat the class name
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FILE: ./src/Countries.php
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FOUND 2 ERRORS AND 7 WARNINGS AFFECTING 6 LINES
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9 | WARNING | The class short comment should describe what the
| | class does and not simply repeat the class name
23 | WARNING | \Drupal calls should be avoided in classes, use
| | dependency injection instead
2042 | WARNING | t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait
| | and $this->t() instead
2042 | WARNING | Only string literals should be passed to t() where
| | possible
2130 | WARNING | \Drupal calls should be avoided in classes, use
| | dependency injection instead
2131 | WARNING | t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait
| | and $this->t() instead
2131 | WARNING | Translatable strings must not begin or end with
| | white spaces, use placeholders with t() for
| | variables
2131 | ERROR | Concatenating translatable strings is not allowed,
| | use placeholders instead and only one string
| | literal
2139 | ERROR | Public method name "Countries::getDBStructure" is
| | not in lowerCamel format
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FILE: ./src/Plugin/Field/FieldFormatter/ContinentDefaultFormatter.php
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FOUND 0 ERRORS AND 1 WARNING AFFECTING 1 LINE
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27 | WARNING | \Drupal calls should be avoided in classes, use
| | dependency injection instead
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FILE: ./src/Plugin/Field/FieldFormatter/CountryDefaultFormatter.php
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FOUND 0 ERRORS AND 1 WARNING AFFECTING 1 LINE
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27 | WARNING | \Drupal calls should be avoided in classes, use
| | dependency injection instead
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FILE: ./src/Plugin/Field/FieldType/ContinentField.php
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FOUND 1 ERROR AND 1 WARNING AFFECTING 2 LINES
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7 | ERROR | [x] Use statements should be sorted alphabetically.
| | The first wrong one is
| | Drupal\Core\Field\FieldStorageDefinitionInterface.
71 | WARNING | [ ] t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait
| | and $this->t() instead
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PHPCBF CAN FIX THE 1 MARKED SNIFF VIOLATIONS AUTOMATICALLY
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FILE: ./src/Plugin/Field/FieldType/CountryField.php
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FOUND 1 ERROR AND 1 WARNING AFFECTING 2 LINES
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7 | ERROR | [x] Use statements should be sorted alphabetically.
| | The first wrong one is
| | Drupal\Core\Field\FieldStorageDefinitionInterface.
71 | WARNING | [ ] t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait
| | and $this->t() instead
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PHPCBF CAN FIX THE 1 MARKED SNIFF VIOLATIONS AUTOMATICALLY
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FILE: ./src/Plugin/Field/FieldWidget/ContinentAjaxWidget.php
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FOUND 1 ERROR AND 2 WARNINGS AFFECTING 3 LINES
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23 | ERROR | [x] @inheritDoc found. Did you mean {@inheritDoc}?
26 | WARNING | [ ] \Drupal calls should be avoided in classes, use
| | dependency injection instead
34 | WARNING | [ ] t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait
| | and $this->t() instead
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PHPCBF CAN FIX THE 1 MARKED SNIFF VIOLATIONS AUTOMATICALLY
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FILE: ./src/Plugin/Field/FieldWidget/ContinentDefaultWidget.php
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FOUND 1 ERROR AND 2 WARNINGS AFFECTING 3 LINES
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23 | ERROR | [x] @inheritDoc found. Did you mean {@inheritDoc}?
26 | WARNING | [ ] \Drupal calls should be avoided in classes, use
| | dependency injection instead
33 | WARNING | [ ] t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait
| | and $this->t() instead
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PHPCBF CAN FIX THE 1 MARKED SNIFF VIOLATIONS AUTOMATICALLY
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FILE: ./src/Plugin/Field/FieldWidget/CountryContinentWidget.php
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FOUND 2 ERRORS AND 5 WARNINGS AFFECTING 7 LINES
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34 | ERROR | [x] @inheritDoc found. Did you mean {@inheritDoc}?
46 | ERROR | [x] @inheritDoc found. Did you mean {@inheritDoc}?
59 | WARNING | [ ] t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait
| | and $this->t() instead
71 | WARNING | [ ] t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait
| | and $this->t() instead
84 | WARNING | [ ] \Drupal calls should be avoided in classes, use
| | dependency injection instead
93 | WARNING | [ ] \Drupal calls should be avoided in classes, use
| | dependency injection instead
100 | WARNING | [ ] Unused private method getFieldName()
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PHPCBF CAN FIX THE 2 MARKED SNIFF VIOLATIONS AUTOMATICALLY
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FILE: ./src/Plugin/Field/FieldWidget/CountryDefaultWidget.php
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FOUND 0 ERRORS AND 3 WARNINGS AFFECTING 3 LINES
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39 | WARNING | t() calls should be avoided in classes, use
| | \Drupal\Core\StringTranslation\StringTranslationTrait
| | and $this->t() instead
52 | WARNING | \Drupal calls should be avoided in classes, use
| | dependency injection instead
70 | WARNING | \Drupal calls should be avoided in classes, use
| | dependency injection instead
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Time: 262ms; Memory: 18MB