Tests: add test for destructuring assignment

Author: sirbrillig

VariableAnalysis/Tests/CodeAnalysis/VariableAnalysisTest.php

@@ -508,4 +508,16 @@ public function testIgnoreUnusedRegexpIgnoresUnusedVariables() {
     ];
     $this->assertEquals($expectedWarnings, $lines);
   }
+
+  public function testAllowDestructuringAssignment() {
+    $fixtureFile = $this->getFixture('DestructuringFixture.php');
+    $phpcsFile = $this->prepareLocalFileForSniffs($this->getSniffFiles(), $fixtureFile);
+    $phpcsFile->process();
+    $lines = $this->getWarningLineNumbersFromFile($phpcsFile);
+    $expectedWarnings = [
+      4,
+      12,
+    ];
+    $this->assertEquals($expectedWarnings, $lines);
+  }
 }

VariableAnalysis/Tests/CodeAnalysis/fixtures/DestructuringFixture.php

@@ -0,0 +1,16 @@
+<?php
+function function_with_destructuring_assignment() {
+    [$a, $b] = [1, 2];
+    [$c, $d] = [3, 4]; // unused
+    echo $a;
+    echo $b;
+    echo $c;
+}
+
+function function_with_destructuring_assignment_using_list() {
+    list( $a, $b ) = [1, 2];
+    list( $c, $d ) = [3, 4]; // unused
+    echo $a;
+    echo $b;
+    echo $c;
+}