diff --git a/WordPress/Sniffs/WP/AlternativeFunctionsSniff.php b/WordPress/Sniffs/WP/AlternativeFunctionsSniff.php
index 40fb0c61c2..9a0a2a9d03 100644
--- a/WordPress/Sniffs/WP/AlternativeFunctionsSniff.php
+++ b/WordPress/Sniffs/WP/AlternativeFunctionsSniff.php
@@ -283,7 +283,7 @@ public function process_matched_token( $stackPtr, $group_name, $matched_content
 				}
 
 				$contains_wp_path_constant = preg_match(
-					'`\b(?:ABSPATH|WP_(?:CONTENT|PLUGIN)_DIR|WPMU_PLUGIN_DIR|TEMPLATEPATH|STYLESHEETPATH|(?:MU)?PLUGINDIR)\b`',
+					'`(?<!->|::)\b(?:ABSPATH|WP_(?:CONTENT|PLUGIN)_DIR|WPMU_PLUGIN_DIR|TEMPLATEPATH|STYLESHEETPATH|(?:MU)?PLUGINDIR)\b`',
 					$filename_param['clean']
 				);
 				if ( 1 === $contains_wp_path_constant ) {
@@ -292,7 +292,7 @@ public function process_matched_token( $stackPtr, $group_name, $matched_content
 				}
 
 				$contains_wp_path_function_call = preg_match(
-					'`(?:get_home_path|plugin_dir_path|get_(?:stylesheet|template)_directory|wp_upload_dir)\s*\(`i',
+					'`(?<!->|::)(?:get_home_path|plugin_dir_path|get_(?:stylesheet|template)_directory|wp_upload_dir)\s*\(`i',
 					$filename_param['clean']
 				);
 				if ( 1 === $contains_wp_path_function_call ) {
@@ -353,7 +353,9 @@ public function process_matched_token( $stackPtr, $group_name, $matched_content
 	 */
 	protected function is_local_data_stream( $clean_param_value ) {
 
-		$stripped = TextStrings::stripQuotes( $clean_param_value );
+		$stripped          = TextStrings::stripQuotes( $clean_param_value );
+		$clean_param_value = ltrim( $clean_param_value, '\\' );
+
 		if ( isset( $this->allowed_local_streams[ $stripped ] )
 			|| isset( $this->allowed_local_stream_constants[ $clean_param_value ] )
 		) {
diff --git a/WordPress/Tests/WP/AlternativeFunctionsUnitTest.inc b/WordPress/Tests/WP/AlternativeFunctionsUnitTest.inc
index a88e5638a9..70b67b1071 100644
--- a/WordPress/Tests/WP/AlternativeFunctionsUnitTest.inc
+++ b/WordPress/Tests/WP/AlternativeFunctionsUnitTest.inc
@@ -32,7 +32,7 @@ file_get_contents( $local_file, true ); // OK.
 file_get_contents( $url, false ); // Warning.
 file_get_contents(); // OK - no params, so nothing to do.
 file_get_contents( 'http://remoteurl.com/file/?w=1' ); // Warning.
-file_get_contents( 'https://wordpress.org' ); // Warning.
+\file_GET_contents( 'https://wordpress.org' ); // Warning.
 file_get_contents(ABSPATH . 'wp-admin/css/some-file.css'); // OK.
 file_get_contents(MYABSPATH . 'plugin-file.json'); // Warning.
 file_get_contents( MUPLUGINDIR . 'some-file.xml' ); // OK.
@@ -147,3 +147,36 @@ file_get_contents(
 	// Not using plugin_dir_path() for reasons.
 	$url
 ); // Warning.
+
+/*
+ * Safeguard correct handling of all types of namespaced function calls
+ */
+\curl_init();
+MyNamespace\parse_url( 'http://example.com/' );
+\MyNamespace\json_encode( $data );
+namespace\unlink(); // The sniff should start flagging this once it can resolve relative namespaces.
+namespace\Sub\strip_tags( $string );
+
+/*
+ * Safeguard that the sniff does not incorrectly ignore class methods/constants with the same
+ * name as WordPress global functions/constants when used in file_get_contents().
+ */
+file_get_contents( MyClass::wp_upload_dir() . 'subdir/file.inc' );
+file_get_contents( $this->GET_HOME_PATH() . 'subdir/file.inc' );
+file_get_contents( $this?->plugin_dir_path() . 'subdir/file.inc' );
+file_get_contents( MyClass::ABSPATH . 'subdir/file.inc' );
+file_get_contents( $this->WPMU_PLUGIN_DIR . 'subdir/file.inc' );
+file_get_contents( $this?->TEMPLATEPATH . 'subdir/file.inc' );
+
+/*
+ * Safeguard correct handling of namespaced variants of STDIN/STDOUT/STDERR constants.
+ *
+ * Note: passing stream resources to these functions is not valid PHP and will be addressed in
+ * https://github.com/WordPress/WordPress-Coding-Standards/issues/2602. These tests document the current behavior of the
+ * sniff.
+ */
+fopen( \STDIN, 'r' );
+file_put_contents( MyNamespace\STDOUT, $data );
+file_get_contents( \MyNamespace\STDIN );
+file_put_contents( namespace\STDERR, $data ); // The sniff should not flag this once it can resolve relative namespaces.
+readfile( namespace\Sub\STDIN );
diff --git a/WordPress/Tests/WP/AlternativeFunctionsUnitTest.php b/WordPress/Tests/WP/AlternativeFunctionsUnitTest.php
index b0f1bf96aa..58f4083729 100644
--- a/WordPress/Tests/WP/AlternativeFunctionsUnitTest.php
+++ b/WordPress/Tests/WP/AlternativeFunctionsUnitTest.php
@@ -89,6 +89,17 @@ public function getWarningList() {
 			131 => 1,
 			142 => 1,
 			146 => 1,
+			154 => 1,
+			164 => 1,
+			165 => 1,
+			166 => 1,
+			167 => 1,
+			168 => 1,
+			169 => 1,
+			179 => 1,
+			180 => 1,
+			181 => 1,
+			182 => 1,
 		);
 	}
 }