Add a "binary integer casing" linter rule

Summary: Adds a linter rule which ensures that binary integers are written in lowercase (i.e. `0b1` instead of `0B1`).

Test Plan: Added test cases.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: Korvin

Differential Revision: https://secure.phabricator.com/D14644

src/__phutil_library_map__.php

@@ -32,6 +32,8 @@ phutil_register_library_map(array(
     'ArcanistBaseXHPASTLinter' => 'lint/linter/ArcanistBaseXHPASTLinter.php',
     'ArcanistBinaryExpressionSpacingXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistBinaryExpressionSpacingXHPASTLinterRule.php',
     'ArcanistBinaryExpressionSpacingXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistBinaryExpressionSpacingXHPASTLinterRuleTestCase.php',
+    'ArcanistBinaryNumericScalarCasingXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistBinaryNumericScalarCasingXHPASTLinterRule.php',
+    'ArcanistBinaryNumericScalarCasingXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistBinaryNumericScalarCasingXHPASTLinterRuleTestCase.php',
     'ArcanistBlacklistedFunctionXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistBlacklistedFunctionXHPASTLinterRule.php',
     'ArcanistBlacklistedFunctionXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistBlacklistedFunctionXHPASTLinterRuleTestCase.php',
     'ArcanistBookmarkWorkflow' => 'workflow/ArcanistBookmarkWorkflow.php',
@@ -434,6 +436,8 @@ phutil_register_library_map(array(
     'ArcanistBaseXHPASTLinter' => 'ArcanistFutureLinter',
     'ArcanistBinaryExpressionSpacingXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
     'ArcanistBinaryExpressionSpacingXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
+    'ArcanistBinaryNumericScalarCasingXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
+    'ArcanistBinaryNumericScalarCasingXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
     'ArcanistBlacklistedFunctionXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
     'ArcanistBlacklistedFunctionXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
     'ArcanistBookmarkWorkflow' => 'ArcanistFeatureWorkflow',

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

@@ -0,0 +1,49 @@
+<?php
+
+final class ArcanistBinaryNumericScalarCasingXHPASTLinterRule
+  extends ArcanistXHPASTLinterRule {
+
+  const ID = 131;
+
+  public function getLintName() {
+    return pht('Binary Integer Casing');
+  }
+
+  public function getLintSeverity() {
+    return ArcanistLintSeverity::SEVERITY_WARNING;
+  }
+
+  public function process(XHPASTNode $root) {
+    $binaries = $this->getBinaryNumericScalars($root);
+
+    foreach ($binaries as $binary) {
+      $value = substr($binary->getConcreteString(), 2);
+
+      if (!preg_match('/^0b[01]+$/', $binary->getConcreteString())) {
+        $this->raiseLintAtNode(
+          $binary,
+          pht(
+            'For consistency, write binary integers with a leading `%s`.',
+            '0b'),
+          '0b'.$value);
+      }
+    }
+  }
+
+  private function getBinaryNumericScalars(XHPASTNode $root) {
+    $numeric_scalars = $root->selectDescendantsOfType('n_NUMERIC_SCALAR');
+    $binary_numeric_scalars = array();
+
+    foreach ($numeric_scalars as $numeric_scalar) {
+      $number = $numeric_scalar->getConcreteString();
+
+      if (preg_match('/^0b[01]+$/i', $number)) {
+        $binary_numeric_scalars[] = $numeric_scalar;
+      }
+    }
+
+    return $binary_numeric_scalars;
+
+  }
+
+}

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

@@ -6,7 +6,7 @@ final class ArcanistHexadecimalNumericScalarCasingXHPASTLinterRule
   const ID = 127;
 
   public function getLintName() {
-    return pht('Hexadecimal Casing');
+    return pht('Hexadecimal Integer Casing');
   }
 
   public function getLintSeverity() {
@@ -23,8 +23,8 @@ final class ArcanistHexadecimalNumericScalarCasingXHPASTLinterRule
         $this->raiseLintAtNode(
           $hexadecimal,
           pht(
-            'For consistency, write hexadecimals in uppercase '.
+            'For consistency, write hexadecimals integers '.
-            'with a leading `%s`.',
+            'in uppercase with a leading `%s`.',
             '0x'),
           '0x'.strtoupper($value));
       }

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

@@ -0,0 +1,11 @@
+<?php
+
+final class ArcanistBinaryNumericScalarCasingXHPASTLinterRuleTestCase
+  extends ArcanistXHPASTLinterRuleTestCase {
+
+  public function testLinter() {
+    $this->executeTestsInDirectory(
+      dirname(__FILE__).'/binary-numeric-scalar-casing/');
+  }
+
+}

src/lint/linter/xhpast/rules/__tests__/binary-numeric-scalar-casing/binary.lint-test

@@ -0,0 +1,5 @@
+<?php
+0b1;
+0B1;
+~~~~~~~~~~
+warning:3:1