Remove the "preg_quote()" lint rule and update the "__CLASS__" lint rule

Summary:
Depends on D21031. Ref T11968. This clears some lint with the word "Future", but is just a minor cleanup patch not really related to the main goal in that task.

We currently warn on `preg_quote()` with no second parameter, but this is valid and correct:

```
preg_match('('.preg_quote($x).')', ...)
```

This is the modern recommended style for this sort of expression, so the warning is often a false positive; drop it.

The "__CLASS__" warning looks for hard-coded class names in strings, but currently looks for them as a word anywhere in the string.

This is often a false positive and sometimes makes error messages or exceptions untranslatable. For example, translators can't do anything with this:

> Filesystem path "%s" does not exist.

...if it's written as:

> %s path "%s" does not exist.

...just because it happens to appear in the class "Filesystem". Some other classes, including "Future", suffer from this.

Even when the detection is correct, it's clunky and a mistake here (failing to update the class name in an error message) is unlikely to ever do any real damage.

Test Plan: Ran unit tests and `arc lint`.

Maniphest Tasks: T11968

Differential Revision: https://secure.phabricator.com/D21032

src/__phutil_library_map__.php

@@ -357,8 +357,6 @@ phutil_register_library_map(array(
     'ArcanistPhutilXHPASTLinterStandard' => 'lint/linter/standards/phutil/ArcanistPhutilXHPASTLinterStandard.php',
     'ArcanistPlusOperatorOnStringsXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistPlusOperatorOnStringsXHPASTLinterRule.php',
     'ArcanistPlusOperatorOnStringsXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistPlusOperatorOnStringsXHPASTLinterRuleTestCase.php',
-    'ArcanistPregQuoteMisuseXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistPregQuoteMisuseXHPASTLinterRule.php',
-    'ArcanistPregQuoteMisuseXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistPregQuoteMisuseXHPASTLinterRuleTestCase.php',
     'ArcanistProjectConfigurationSource' => 'config/source/ArcanistProjectConfigurationSource.php',
     'ArcanistPrompt' => 'toolset/ArcanistPrompt.php',
     'ArcanistPublicPropertyXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistPublicPropertyXHPASTLinterRule.php',
@@ -1299,8 +1297,6 @@ phutil_register_library_map(array(
     'ArcanistPhutilXHPASTLinterStandard' => 'ArcanistLinterStandard',
     'ArcanistPlusOperatorOnStringsXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
     'ArcanistPlusOperatorOnStringsXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
-    'ArcanistPregQuoteMisuseXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
-    'ArcanistPregQuoteMisuseXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
     'ArcanistProjectConfigurationSource' => 'ArcanistWorkingCopyConfigurationSource',
     'ArcanistPrompt' => 'Phobject',
     'ArcanistPublicPropertyXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',

src/lint/linter/xhpast/rules/ArcanistClassNameLiteralXHPASTLinterRule.php

@@ -34,7 +34,20 @@ final class ArcanistClassNameLiteralXHPASTLinterRule
           $replacement = '__CLASS__';
         }
 
-        $regex = '/\b'.preg_quote($class_name, '/').'\b/';
+        // NOTE: We're only warning when the entire string content is the
+        // class name. It's okay to hard-code the class name as part of a
+        // longer string, like an error or exception message.
+
+        // Sometimes the class name (like "Filesystem") is also a valid part
+        // of the message, which makes this warning a false positive.
+
+        // Even when we're generating a true positive by detecting a class
+        // name in part of a longer string, the cost of an error message
+        // being out-of-date is generally very small (mild confusion, but
+        // no incorrect beahavior) and using "__CLASS__" in errors is often
+        // clunky.
+
+        $regex = '(^'.preg_quote($class_name).'$)';
         if (!preg_match($regex, $contents)) {
           continue;
         }
@@ -42,8 +55,7 @@ final class ArcanistClassNameLiteralXHPASTLinterRule
         $this->raiseLintAtNode(
           $string,
           pht(
-            "Don't hard-code class names, use `%s` instead.",
-            '__CLASS__'),
+            'Prefer "__CLASS__" over hard-coded class names.'),
           $replacement);
       }
     }

src/lint/linter/xhpast/rules/ArcanistPregQuoteMisuseXHPASTLinterRule.php

@@ -1,42 +0,0 @@
-<?php
-
-/**
- * @{function:preg_quote} takes two arguments, but the second one is optional
- * because it is possible to use `()`, `[]` or `{}` as regular expression
- * delimiters. If you don't pass a second argument, you're probably going to
- * get something wrong.
- */
-final class ArcanistPregQuoteMisuseXHPASTLinterRule
-  extends ArcanistXHPASTLinterRule {
-
-  const ID = 14;
-
-  public function getLintName() {
-    return pht('Misuse of `%s`', 'preg_quote');
-  }
-
-  public function getLintSeverity() {
-    return ArcanistLintSeverity::SEVERITY_ADVICE;
-  }
-
-  public function process(XHPASTNode $root) {
-    $function_calls = $this->getFunctionCalls($root, array('preg_quote'));
-
-    foreach ($function_calls as $call) {
-      $parameter_list = $call->getChildOfType(1, 'n_CALL_PARAMETER_LIST');
-      if (count($parameter_list->getChildren()) !== 2) {
-        $this->raiseLintAtNode(
-          $call,
-          pht(
-            'If you use pattern delimiters that require escaping '.
-            '(such as `%s`, but not `%s`) then you should pass two '.
-            'arguments to %s, so that %s knows which delimiter to escape.',
-            '//',
-            '()',
-            'preg_quote',
-            'preg_quote'));
-      }
-    }
-  }
-
-}

src/lint/linter/xhpast/rules/__tests__/ArcanistPregQuoteMisuseXHPASTLinterRuleTestCase.php

@@ -1,10 +0,0 @@
-<?php
-
-final class ArcanistPregQuoteMisuseXHPASTLinterRuleTestCase
-  extends ArcanistXHPASTLinterRuleTestCase {
-
-  public function testLinter() {
-    $this->executeTestsInDirectory(dirname(__FILE__).'/preg_quote-misuse/');
-  }
-
-}

src/lint/linter/xhpast/rules/__tests__/class-name-literal/class-name-literal.lint-test

@@ -6,10 +6,15 @@ class MyClass {
   }
 
   public function someOtherMethod() {
-    $x = 'MyClass is awesome';
+    $x = 'MyClass';
     $y = 'MyClassIsAwesome';
+    $z = 'MyClass is awesome';
     return __CLASS__;
   }
+
+  public function throwAnException() {
+    throw new Exception('MyClass is throwing an exception!');
+  }
 }
 
 $c = new class {
@@ -29,10 +34,15 @@ class MyClass {
   }
 
   public function someOtherMethod() {
-    $x = 'MyClass is awesome';
+    $x = __CLASS__;
     $y = 'MyClassIsAwesome';
+    $z = 'MyClass is awesome';
     return __CLASS__;
   }
+
+  public function throwAnException() {
+    throw new Exception('MyClass is throwing an exception!');
+  }
 }
 
 $c = new class {

src/lint/linter/xhpast/rules/__tests__/preg_quote-misuse/preg_quote-misuse.lint-test

@@ -1,11 +0,0 @@
-<?php
-
-function foo($bar) {
-  preg_quote($bar);
-  preg_quote($bar, '/');
-  preg_Quote('moo');
-  preg_quote('moo', '/');
-}
-~~~~~~~~~~
-advice:4:3:XHP14:Misuse of `preg_quote`
-advice:6:3:XHP14:Misuse of `preg_quote`