Turn LinterTrait into an abstract class BaseLinter

Author: Atry

src/Linters/LinterTrait.hack renamed to src/Linters/BaseLinter.hack

@@ -12,9 +12,8 @@ namespace Facebook\HHAST;
 use type Facebook\HHAST\File;
 use namespace HH\Lib\{C, Str};
 
-<<__ConsistentConstruct>>
-trait LinterTrait {
-  require implements Linter;
+<<__ConsistentConstruct, __Sealed(SingleRuleLinter::class, HHClientLinter::class)>>
+abstract class BaseLinter implements Linter {
 
   public static function shouldLintFile(File $_): bool {
     return true;

src/Linters/HHClientLinter.hack

@@ -15,8 +15,7 @@ use namespace HH\Lib\{C, Str, Vec};
 /**
  * A linter as a proxy invoking `hh_client --lint`.
  */
-final class HHClientLinter implements Linter {
-  use LinterTrait;
+final class HHClientLinter extends BaseLinter {
   use SuppressibleTrait;
 
   const type TConfig = shape();
@@ -63,13 +62,13 @@ final class HHClientLinter implements Linter {
       |> Vec\map(
         $$,
         $error ==> new HHClientLintError(
-          $this->file,
+          $this->getFile(),
           $error,
           $this::blameCode($file_lines, $error),
         ),
       )
       |> Vec\filter($$, $error ==> {
-        if ($error->getLintRule()->isSuppressedForFile($this->file)) {
+        if ($error->getLintRule()->isSuppressedForFile($this->getFile())) {
           return false;
         }
         $range = $error->getRange();
@@ -78,12 +77,12 @@ final class HHClientLinter implements Linter {
         }
         list(list($line_number, $_), $_) = $range;
         $previous_line_number = $line_number - 1;
-        if ($this->isSuppressedForLine($this->file, $previous_line_number)) {
+        if ($this->isSuppressedForLine($this->getFile(), $previous_line_number)) {
           return false;
         }
         if (
           $error->getLintRule()
-            ->isSuppressedForLine($this->file, $previous_line_number)
+            ->isSuppressedForLine($this->getFile(), $previous_line_number)
         ) {
           return false;
         }

src/Linters/Linter.hack

@@ -15,7 +15,7 @@ namespace Facebook\HHAST;
  * Problems found by a Linter could associated with different LintRules,
  * especially when the Linter is a proxy calling other linting tools.
  */
-<<__Sealed(SingleRuleLinter::class, HHClientLinter::class)>>
+<<__Sealed(BaseLinter::class)>>
 interface Linter {
   <<__Reifiable>>
   abstract const type TConfig;

src/Linters/SingleRuleLinter.hack

@@ -12,8 +12,7 @@ namespace Facebook\HHAST;
 /**
  * A linter that applies a single lint rule.
  */
-abstract class SingleRuleLinter implements LintRule, Linter {
-  use LinterTrait;
+abstract class SingleRuleLinter extends BaseLinter implements LintRule {
   use SuppressibleTrait;
 
   final public function getName(): string {