diff --git a/.gitattributes b/.gitattributes
index a5666637cb..97cb2461f6 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,2 +1,3 @@
 # Auto detect text files and perform EOL normalization
 * text=auto eol=lf
+tests/data/*-win.php eol=crlf
diff --git a/features/bootstrap/FeatureContext.php b/features/bootstrap/FeatureContext.php
index fd7c014077..5ceb818902 100644
--- a/features/bootstrap/FeatureContext.php
+++ b/features/bootstrap/FeatureContext.php
@@ -159,7 +159,7 @@ private static function terminate_proc( $master_pid ) {
 
 		$output = `ps -o ppid,pid,command | grep $master_pid`;
 
-		foreach ( explode( PHP_EOL, $output ) as $line ) {
+		foreach ( explode( "\n", $output ) as $line ) {
 			if ( preg_match( '/^\s*(\d+)\s+(\d+)/', $line, $matches ) ) {
 				$parent = $matches[1];
 				$child = $matches[2];
@@ -393,7 +393,7 @@ public function move_files( $src, $dest ) {
 	public function add_line_to_wp_config( &$wp_config_code, $line ) {
 		$token = "/* That's all, stop editing!";
 
-		$wp_config_code = str_replace( $token, "$line\n\n$token", $wp_config_code );
+		$wp_config_code = str_replace( $token, $line. PHP_EOL . PHP_EOL . $token, $wp_config_code );
 	}
 
 	public function download_wp( $subdir = '' ) {
diff --git a/features/bootstrap/support.php b/features/bootstrap/support.php
index a37a064f65..390cdc3a03 100644
--- a/features/bootstrap/support.php
+++ b/features/bootstrap/support.php
@@ -143,7 +143,7 @@ function checkThatJsonStringContainsJsonString( $actualJson, $expectedJson ) {
  * @return bool     Whether $actualCSV contains $expectedCSV
  */
 function checkThatCsvStringContainsValues( $actualCSV, $expectedCSV ) {
-	$actualCSV = array_map( 'str_getcsv', explode( PHP_EOL, $actualCSV ) );
+	$actualCSV = array_map( 'str_getcsv', explode( "\n", $actualCSV ) );
 
 	if ( empty( $actualCSV ) )
 		return false;
diff --git a/features/steps/given.php b/features/steps/given.php
index 4482327804..2d25157ecb 100644
--- a/features/steps/given.php
+++ b/features/steps/given.php
@@ -31,7 +31,7 @@ function ( $world, $path, PyStringNode $content ) {
 		$content = (string) $content . "\n";
 		$full_path = $world->variables['RUN_DIR'] . "/$path";
 		Process::create( \WP_CLI\utils\esc_cmd( 'mkdir -p %s', dirname( $full_path ) ) )->run_check();
-		file_put_contents( $full_path, $content );
+		file_put_contents( $full_path, WP_CLI\Utils\denormalize_newlines( $content ) );
 	}
 );
 
@@ -88,7 +88,7 @@ function ( $world, $type = 'subdirectory' ) {
 
 $steps->Given( '/^these installed and active plugins:$/',
 	function( $world, $stream ) {
-		$plugins = implode( ' ', array_map( 'trim', explode( PHP_EOL, (string)$stream ) ) );
+		$plugins = implode( ' ', array_map( 'trim', explode( "\n", (string)$stream ) ) );
 		$world->proc( "wp plugin install $plugins --activate" )->run_check();
 	}
 );
diff --git a/features/steps/then.php b/features/steps/then.php
index 8875554859..76d5354659 100644
--- a/features/steps/then.php
+++ b/features/steps/then.php
@@ -193,7 +193,7 @@ function ( $world, $path, $type, $action, $expected = null ) {
 				foreach( $files as &$file ) {
 					$file = str_replace( $path . '/', '', $file );
 				}
-				$contents = implode( PHP_EOL, $files );
+				$contents = implode( "\n", $files );
 			}
 			checkString( $contents, $expected, $action );
 		}
diff --git a/features/steps/when.php b/features/steps/when.php
index afe3f7a0df..659f53a674 100644
--- a/features/steps/when.php
+++ b/features/steps/when.php
@@ -29,6 +29,8 @@ function ( $world, $cmd ) {
 	function ( $world, $mode, $cmd ) {
 		$cmd = $world->replace_variables( $cmd );
 		$world->result = invoke_proc( $world->proc( $cmd ), $mode );
+		$world->result->stdout = WP_CLI\Utils\normalize_newlines( $world->result->stdout );
+		$world->result->stderr = WP_CLI\Utils\normalize_newlines( $world->result->stderr );
 		list( $world->result->stdout, $world->email_sends ) = capture_email_sends( $world->result->stdout );
 	}
 );
@@ -37,6 +39,8 @@ function ( $world, $mode, $cmd ) {
 	function ( $world, $mode, $cmd, $subdir ) {
 		$cmd = $world->replace_variables( $cmd );
 		$world->result = invoke_proc( $world->proc( $cmd, array(), $subdir ), $mode );
+		$world->result->stdout = WP_CLI\Utils\normalize_newlines( $world->result->stdout );
+		$world->result->stderr = WP_CLI\Utils\normalize_newlines( $world->result->stderr );
 		list( $world->result->stdout, $world->email_sends ) = capture_email_sends( $world->result->stdout );
 	}
 );
@@ -48,6 +52,8 @@ function ( $world, $mode ) {
 
 		$proc = Process::create( $world->result->command, $world->result->cwd, $world->result->env );
 		$world->result = invoke_proc( $proc, $mode );
+		$world->result->stdout = WP_CLI\Utils\normalize_newlines( $world->result->stdout );
+		$world->result->stderr = WP_CLI\Utils\normalize_newlines( $world->result->stderr );
 		list( $world->result->stdout, $world->email_sends ) = capture_email_sends( $world->result->stdout );
 	}
 );
diff --git a/php/WP_CLI/Bootstrap/IncludeFrameworkAutoloader.php b/php/WP_CLI/Bootstrap/IncludeFrameworkAutoloader.php
index 910ec8355c..d2301dcd73 100644
--- a/php/WP_CLI/Bootstrap/IncludeFrameworkAutoloader.php
+++ b/php/WP_CLI/Bootstrap/IncludeFrameworkAutoloader.php
@@ -43,7 +43,7 @@ protected function get_autoloader_paths() {
 	protected function handle_failure() {
 		fputs(
 			STDERR,
-			"Internal error: Can't find Composer autoloader.\nTry running: composer install\n"
+			'Internal error: Can\'t find Composer autoloader.' . PHP_EOL . 'Try running: composer install' . PHP_EOL
 		);
 		exit( 3 );
 	}
diff --git a/php/WP_CLI/Configurator.php b/php/WP_CLI/Configurator.php
index 2def54f1e9..70fdf19555 100644
--- a/php/WP_CLI/Configurator.php
+++ b/php/WP_CLI/Configurator.php
@@ -200,7 +200,7 @@ private function unmix_assoc_args( $mixed_args, $global_assoc = array(), $local_
 	private function assoc_arg_to_runtime_config( $key, $value, &$runtime_config ) {
 		$details = $this->spec[ $key ];
 		if ( isset( $details['deprecated'] ) ) {
-			fwrite( STDERR, "WP-CLI: The --{$key} global parameter is deprecated. {$details['deprecated']}\n" );
+			fwrite( STDERR, "WP-CLI: The --{$key} global parameter is deprecated. {$details['deprecated']}" . PHP_EOL );
 		}
 
 		if ( $details['multiple'] ) {
diff --git a/php/WP_CLI/Dispatcher/Subcommand.php b/php/WP_CLI/Dispatcher/Subcommand.php
index a50dcf8113..a21c621673 100644
--- a/php/WP_CLI/Dispatcher/Subcommand.php
+++ b/php/WP_CLI/Dispatcher/Subcommand.php
@@ -36,7 +36,7 @@ function __construct( $parent, $name, $docparser, $when_invoked ) {
 	 * @return string
 	 */
 	private static function extract_synopsis( $longdesc ) {
-		preg_match_all( '/(.+?)[\r\n]+:/', $longdesc, $matches );
+		preg_match_all( '/(.+?)\n+:/', $longdesc, $matches );
 		return implode( ' ', $matches[1] );
 	}
 
@@ -276,8 +276,8 @@ private function validate_args( $args, $assoc_args, $extra_args ) {
 		$i = 0;
 		$errors = array( 'fatal' => array(), 'warning' => array() );
 		$mock_doc = array( $this->get_shortdesc(), '' );
-		$mock_doc = array_merge( $mock_doc, explode( PHP_EOL, $this->get_longdesc() ) );
-		$mock_doc = '/**' . PHP_EOL . '* ' . implode( PHP_EOL . '* ', $mock_doc ) . PHP_EOL . '*/';
+		$mock_doc = array_merge( $mock_doc, explode( "\n", $this->get_longdesc() ) );
+		$mock_doc = "/**\n* " . implode( "\n* ", $mock_doc ) . "\n*/";
 		$docparser = new \WP_CLI\DocParser( $mock_doc );
 		foreach( $synopsis_spec as $spec ) {
 			if ( 'positional' === $spec['type'] ) {
@@ -335,7 +335,7 @@ private function validate_args( $args, $assoc_args, $extra_args ) {
 				$errors['fatal'][] = sprintf(
 					'unknown --%s parameter%s',
 					$key,
-					! empty( $suggestion ) ? PHP_EOL . "Did you mean '--{$suggestion}'?" : ''
+					! empty( $suggestion ) ? "\nDid you mean '--{$suggestion}'?" : ''
 				);
 			}
 		}
diff --git a/php/WP_CLI/DocParser.php b/php/WP_CLI/DocParser.php
index a6f4cb9338..daa3708ab6 100644
--- a/php/WP_CLI/DocParser.php
+++ b/php/WP_CLI/DocParser.php
@@ -19,6 +19,7 @@ class DocParser {
 	 * @param string $docComment
 	 */
 	public function __construct( $docComment ) {
+		$docComment = Utils\normalize_newlines( $docComment );
 		$this->docComment = self::remove_decorations( $docComment );
 	}
 
@@ -29,7 +30,7 @@ public function __construct( $docComment ) {
 	 * @return string
 	 */
 	private static function remove_decorations( $comment ) {
-		$comment = preg_replace( '|^/\*\*[\r\n]+|', '', $comment );
+		$comment = preg_replace( '|^/\*\*\n+|', '', $comment );
 		$comment = preg_replace( '|\n[\t ]*\*/$|', '', $comment );
 		$comment = preg_replace( '|^[\t ]*\* ?|m', '', $comment );
 
@@ -155,7 +156,7 @@ public function get_param_args( $key ) {
 	 * @return array|null Interpreted YAML document, or null.
 	 */
 	private function get_arg_or_param_args( $regex ) {
-		$bits = explode( PHP_EOL, $this->docComment );
+		$bits = explode( "\n", $this->docComment );
 		$within_arg = $within_doc = false;
 		$document = array();
 		foreach( $bits as $bit ) {
@@ -182,7 +183,7 @@ private function get_arg_or_param_args( $regex ) {
 		}
 
 		if ( $document ) {
-			return Spyc::YAMLLoadString( implode( PHP_EOL, $document ) );
+			return Spyc::YAMLLoadString( implode( "\n", $document ) );
 		}
 		return null;
 	}
diff --git a/php/WP_CLI/Loggers/Base.php b/php/WP_CLI/Loggers/Base.php
index 129ee70034..9e401e7271 100644
--- a/php/WP_CLI/Loggers/Base.php
+++ b/php/WP_CLI/Loggers/Base.php
@@ -54,7 +54,7 @@ public function debug( $message, $group = false ) {
 	 * @param string $str Message to write.
 	 */
 	protected function write( $handle, $str ) {
-		fwrite( $handle, $str );
+		fwrite( $handle, \WP_CLI\Utils\denormalize_newlines( $str ) );
 	}
 
 	/**
diff --git a/php/WP_CLI/ProcessRun.php b/php/WP_CLI/ProcessRun.php
index aedc5f65da..afd578417a 100644
--- a/php/WP_CLI/ProcessRun.php
+++ b/php/WP_CLI/ProcessRun.php
@@ -51,9 +51,9 @@ public function __construct( $props ) {
 	 * @return string
 	 */
 	public function __toString() {
-		$out  = "$ $this->command\n";
-		$out .= "$this->stdout\n$this->stderr";
-		$out .= "cwd: $this->cwd\n";
+		$out  = "$ $this->command" . PHP_EOL;
+		$out .= Utils\denormalize_newlines( $this->stdout ) . PHP_EOL . Utils\denormalize_newlines( $this->stderr );
+		$out .= "cwd: $this->cwd" . PHP_EOL;
 		$out .= "exit status: $this->return_code";
 
 		return $out;
diff --git a/php/WP_CLI/Runner.php b/php/WP_CLI/Runner.php
index 44bab83291..0fd70b86f1 100644
--- a/php/WP_CLI/Runner.php
+++ b/php/WP_CLI/Runner.php
@@ -267,14 +267,14 @@ public function find_command_to_run( $args ) {
 						$child,
 						$parent_name,
 						$parent_name,
-						! empty( $suggestion ) ? PHP_EOL . "Did you mean '{$suggestion}'?" : ''
+						! empty( $suggestion ) ? "\nDid you mean '{$suggestion}'?" : ''
 					);
 				} else {
 					$suggestion = $this->get_subcommand_suggestion( $full_name, $command );
 					return sprintf(
 						"'%s' is not a registered wp command. See 'wp help'.%s",
 						$full_name,
-						! empty( $suggestion ) ? PHP_EOL . "Did you mean '{$suggestion}'?" : ''
+						! empty( $suggestion ) ? "\nDid you mean '{$suggestion}'?" : ''
 					);
 				}
 			}
@@ -430,7 +430,7 @@ public function is_command_disabled( $command ) {
 	public function get_wp_config_code() {
 		$wp_config_path = Utils\locate_wp_config();
 
-		$wp_config_code = explode( "\n", file_get_contents( $wp_config_path ) );
+		$wp_config_code = explode( "\n", Utils\normalize_newlines( file_get_contents( $wp_config_path ) ) );
 
 		$found_wp_settings = false;
 
@@ -804,7 +804,7 @@ public function start() {
 				$error_msg = "Alias '{$this->alias}' not found.";
 				$suggestion = Utils\get_suggestion( $this->alias, array_keys( $this->aliases ), $threshold = 2 );
 				if ( $suggestion ) {
-					$error_msg .= PHP_EOL . "Did you mean '{$suggestion}'?";
+					$error_msg .= "\nDid you mean '{$suggestion}'?";
 				}
 				WP_CLI::error( $error_msg );
 			}
diff --git a/php/boot-fs.php b/php/boot-fs.php
index 7ee5da0746..f07b2b8f89 100644
--- a/php/boot-fs.php
+++ b/php/boot-fs.php
@@ -3,12 +3,12 @@
 // This file needs to parse without error in PHP < 5.3
 
 if ( 'cli' !== PHP_SAPI ) {
-	echo "Only CLI access.\n";
+	echo 'Only CLI access.' . PHP_EOL;
 	die(-1);
 }
 
 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) ) {
-	printf( "Error: WP-CLI requires PHP %s or newer. You are running version %s.\n", '5.3.0', PHP_VERSION );
+	printf( 'Error: WP-CLI requires PHP %s or newer. You are running version %s.' . PHP_EOL, '5.3.0', PHP_VERSION );
 	die(-1);
 }
 
diff --git a/php/class-wp-cli.php b/php/class-wp-cli.php
index 799bb3b307..91fe3dde03 100644
--- a/php/class-wp-cli.php
+++ b/php/class-wp-cli.php
@@ -488,9 +488,9 @@ public static function add_command( $name, $callable, $args = array() ) {
 				$long_desc = '';
 				$bits = explode( ' ', $synopsis );
 				foreach( $args['synopsis'] as $key => $arg ) {
-					$long_desc .= $bits[ $key ] . PHP_EOL;
+					$long_desc .= $bits[ $key ] . "\n";
 					if ( ! empty( $arg['description'] ) ) {
-						$long_desc .= ': ' . $arg['description'] . PHP_EOL;
+						$long_desc .= ': ' . $arg['description'] . "\n";
 					}
 					$yamlify = array();
 					foreach( array( 'default', 'options' ) as $key ) {
@@ -500,13 +500,13 @@ public static function add_command( $name, $callable, $args = array() ) {
 					}
 					if ( ! empty( $yamlify ) ) {
 						$long_desc .= Spyc::YAMLDump( $yamlify );
-						$long_desc .= '---' . PHP_EOL;
+						$long_desc .= '---' . "\n";
 					}
-					$long_desc .= PHP_EOL;
+					$long_desc .= "\n";
 				}
 				if ( ! empty( $long_desc ) ) {
-					$long_desc = rtrim( $long_desc, PHP_EOL );
-					$long_desc = '## OPTIONS' . PHP_EOL . PHP_EOL . $long_desc;
+					$long_desc = rtrim( $long_desc, "\n" );
+					$long_desc = '## OPTIONS' . "\n\n" . $long_desc;
 					$leaf_command->set_longdesc( $long_desc );
 				}
 			}
@@ -587,7 +587,7 @@ public static function remove_deferred_addition( $name ) {
 	 * @return null
 	 */
 	public static function line( $message = '' ) {
-		echo $message . "\n";
+		echo Utils\denormalize_newlines( $message . "\n" );
 	}
 
 	/**
@@ -862,7 +862,7 @@ public static function print_value( $value, $assoc_args = array() ) {
 			$value = var_export( $value );
 		}
 
-		echo $value . "\n";
+		echo Utils\denormalize_newlines( $value . "\n" );
 	}
 
 	/**
diff --git a/php/commands/help.php b/php/commands/help.php
index c262561e98..6bdffc056e 100644
--- a/php/commands/help.php
+++ b/php/commands/help.php
@@ -105,6 +105,7 @@ private static function show_help( $command ) {
 		// section headers
 		$out = preg_replace( '/^## ([A-Z ]+)/m', WP_CLI::colorize( '%9\1%n' ), $out );
 
+		$out = Utils\denormalize_newlines( $out );
 		self::pass_through_pager( $out );
 	}
 
diff --git a/php/commands/src/CLI_Command.php b/php/commands/src/CLI_Command.php
index 7de79f4f5b..3c24c5c902 100644
--- a/php/commands/src/CLI_Command.php
+++ b/php/commands/src/CLI_Command.php
@@ -310,7 +310,7 @@ public function update( $_, $assoc_args ) {
 		$process = WP_CLI\Process::create( "{$php_binary} $temp --info {$allow_root}" );
 		$result = $process->run();
 		if ( 0 !== $result->return_code || false === stripos( $result->stdout, 'WP-CLI version:' ) ) {
-			$multi_line = explode( PHP_EOL, $result->stderr );
+			$multi_line = explode( "\n", Utils\normalize_newlines( $result->stderr ) );
 			WP_CLI::error_multi_line( $multi_line );
 			WP_CLI::error( 'The downloaded PHAR is broken, try running wp cli update again.' );
 		}
diff --git a/php/utils.php b/php/utils.php
index 54c141b65d..05c4a8d7ac 100644
--- a/php/utils.php
+++ b/php/utils.php
@@ -56,7 +56,7 @@ function load_dependencies() {
 	}
 
 	if ( !$has_autoload ) {
-		fputs( STDERR, "Internal error: Can't find Composer autoloader.\nTry running: composer install\n" );
+		fputs( STDERR, 'Internal error: Can\'t find Composer autoloader.' . PHP_EOL . 'Try running: composer install' . PHP_EOL );
 		exit(3);
 	}
 }
@@ -1023,3 +1023,28 @@ function force_env_on_nix_systems( $command ) {
 	}
 	return $command;
 }
+
+/**
+ * Normalize Windows newlines to Unix ones.
+ *
+ * @param string $str
+ *
+ * @return string
+ */
+function normalize_newlines( $str ) {
+	return str_replace( "\r\n", "\n", $str );
+}
+
+/**
+ * Denormalize Unix newlines to Windows ones if on Windows.
+ *
+ * @param string $str
+ *
+ * @return string
+ */
+function denormalize_newlines( $str ) {
+	if ( is_windows() ) {
+		return preg_replace( '/(?<!\r)\n/', "\r\n", $str );
+	}
+	return $str;
+}
diff --git a/tests/data/commandfactory-doc_comment-class-win.php b/tests/data/commandfactory-doc_comment-class-win.php
new file mode 100644
index 0000000000..64ff0801a7
--- /dev/null
+++ b/tests/data/commandfactory-doc_comment-class-win.php
@@ -0,0 +1,70 @@
+<?php
+
+/**
+ * Basic class
+ *
+ * ## EXAMPLES
+ *
+ *     # Foo.
+ *     $ wp foo
+ */
+class CommandFactoryTests_Get_Doc_Comment_1_Command_Win extends WP_CLI_Command {
+	/**
+	 * Command1 method
+	 *
+	 * ## OPTIONS
+	 *
+	 * ## EXAMPLES
+	 *
+	 *     $ wp foo command1 public
+	 */
+	function command1() {
+	}
+
+	/**
+	 * Command2 function
+	 *
+	 * ## OPTIONS
+	 *
+	 * [--path=<path>]
+	 *
+	 * ## EXAMPLES
+	 *
+	 *     $ wp foo command2 --path=/**a/**b/**c/**
+	 */
+
+final
+			protected
+			static
+	function
+			command2() {
+	}
+
+	/**
+	 * Command3 function
+	 *
+	 * ## OPTIONS
+	 *
+	 * [--path=<path>]
+	 *
+	 * ## EXAMPLES
+	 *
+	 *     $ wp foo command3 --path=/**a/**b/**c/**
+	 function*/public function command3( $function ) {}
+
+	function command4() {}
+}
+
+/**
+ * Basic class
+ *
+ * ## EXAMPLES
+ *
+ *     # Foo.
+ *     $ wp foo --final abstract
+ class*/abstract class
+  CommandFactoryTests_Get_Doc_Comment_2_Command_Win
+ extends              WP_CLI_Command
+    {
+		function command1() {}
+	}
diff --git a/tests/data/commandfactory-doc_comment-function-win.php b/tests/data/commandfactory-doc_comment-function-win.php
new file mode 100644
index 0000000000..7fa1382e9a
--- /dev/null
+++ b/tests/data/commandfactory-doc_comment-function-win.php
@@ -0,0 +1,19 @@
+<?php
+
+/**
+ * foo
+ */
+function commandfactorytests_get_doc_comment_func_1_win( $function = blah ) {
+}
+
+/**
+ * bar
+ function*/function commandfactorytests_get_doc_comment_func_2_win( $function = blah ) {
+}
+
+/**
+ * /** baz
+ */$commandfactorytests_get_doc_comment_func_3_win
+  =
+  	function ( $args ) {
+};
diff --git a/tests/test-commandfactory.php b/tests/test-commandfactory.php
index 329afa3414..bf2ab11a54 100644
--- a/tests/test-commandfactory.php
+++ b/tests/test-commandfactory.php
@@ -10,6 +10,10 @@ class CommandFactoryTests extends PHPUnit_Framework_TestCase {
 	 * @dataProvider dataProviderExtractLastDocComment
 	 */
 	function testExtractLastDocComment( $content, $expected ) {
+		// Save and set test env var.
+		$is_windows = getenv( 'WP_CLI_TEST_IS_WINDOWS' );
+		putenv( 'WP_CLI_TEST_IS_WINDOWS=0' );
+
 		static $extract_last_doc_comment = null;
 		if ( null === $extract_last_doc_comment ) {
 			$extract_last_doc_comment = new \ReflectionMethod( 'WP_CLI\Dispatcher\CommandFactory', 'extract_last_doc_comment' );
@@ -18,6 +22,30 @@ function testExtractLastDocComment( $content, $expected ) {
 
 		$actual = $extract_last_doc_comment->invoke( null, $content );
 		$this->assertSame( $expected, $actual );
+
+		// Restore.
+		putenv( false === $is_windows ? 'WP_CLI_TEST_IS_WINDOWS' : "WP_CLI_TEST_IS_WINDOWS=$is_windows" );
+	}
+
+	/**
+	 * @dataProvider dataProviderExtractLastDocComment
+	 */
+	function testExtractLastDocCommentWin( $content, $expected ) {
+		// Save and set test env var.
+		$is_windows = getenv( 'WP_CLI_TEST_IS_WINDOWS' );
+		putenv( 'WP_CLI_TEST_IS_WINDOWS=1' );
+
+		static $extract_last_doc_comment = null;
+		if ( null === $extract_last_doc_comment ) {
+			$extract_last_doc_comment = new \ReflectionMethod( 'WP_CLI\Dispatcher\CommandFactory', 'extract_last_doc_comment' );
+			$extract_last_doc_comment->setAccessible( true );
+		}
+
+		$actual = $extract_last_doc_comment->invoke( null, $content );
+		$this->assertSame( $expected, $actual );
+
+		// Restore.
+		putenv( false === $is_windows ? 'WP_CLI_TEST_IS_WINDOWS' : "WP_CLI_TEST_IS_WINDOWS=$is_windows" );
 	}
 
 	function dataProviderExtractLastDocComment() {
@@ -29,6 +57,7 @@ function dataProviderExtractLastDocComment() {
 			array( "/***/ */", false ),
 			array( "/***/", "/***/" ),
 			array( "\n /**\n  \n  \t\n  */ \t\n \n ", "/**\n  \n  \t\n  */" ),
+			array( "\r\n /**\r\n  \r\n  \t\r\n  */ \t\r\n \r\n ", "/**\r\n  \r\n  \t\r\n  */" ),
 			array( "/**/ /***/ /***/", "/***/" ),
 			array( "asdfasdf/** /** */", "/** /** */" ),
 			array( "*//** /** */", "/** /** */" ),
@@ -39,11 +68,13 @@ function dataProviderExtractLastDocComment() {
 			array( "/** */class qwer", "/** */" ),
 			array( "/**1*/class qwer{}/**2*/class asdf", "/**2*/" ),
 			array( "/** */class qwer {}\nclass asdf", false ),
+			array( "/** */class qwer {}\r\nclass asdf", false ),
 
 			array( "/** */function qwer", "/** */" ),
 			array( "/** */function qwer( \$function ) {}", "/** */" ),
 			array( "/**1*/function qwer() {}/**2*/function asdf()", "/**2*/" ),
 			array( "/** */function qwer() {}\nfunction asdf()", false ),
+			array( "/** */function qwer() {}\r\nfunction asdf()", false ),
 			array( "/** */function qwer() {}function asdf()", false ),
 			array( "/** */function qwer() {};function asdf( \$function )", false ),
 		);
@@ -51,14 +82,22 @@ function dataProviderExtractLastDocComment() {
 
 	function testGetDocComment() {
 		// Save and set test env var.
-		$prev_test_get_doc_comment = getenv( 'WP_CLI_TEST_GET_DOC_COMMENT' );
+		$get_doc_comment = getenv( 'WP_CLI_TEST_GET_DOC_COMMENT' );
+		$is_windows = getenv( 'WP_CLI_TEST_IS_WINDOWS' );
+
 		putenv( 'WP_CLI_TEST_GET_DOC_COMMENT=1' );
+		putenv( 'WP_CLI_TEST_IS_WINDOWS=0' );
 
 		// Make private function accessible.
 		$get_doc_comment = new \ReflectionMethod( 'WP_CLI\Dispatcher\CommandFactory', 'get_doc_comment' );
 		$get_doc_comment->setAccessible( true );
 
-		require __DIR__ . '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/data/commandfactory-doc_comment-class.php';
+		if ( ! class_exists( 'CommandFactoryTests_Get_Doc_Comment_1_Command', false ) ) {
+			require __DIR__ . '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/data/commandfactory-doc_comment-class.php';
+		}
+		if ( ! class_exists( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win', false ) ) {
+			require __DIR__ . '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/data/commandfactory-doc_comment-class-win.php';
+		}
 
 		// Class 1
 
@@ -101,6 +140,47 @@ function testGetDocComment() {
 		$this->assertSame( $expected, $actual );
 		$this->assertFalse( $actual );
 
+		// Class 1 Windows
+
+		$reflection = new \ReflectionClass( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 1
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win', 'command1' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 2
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win', 'command2' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 3
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win', 'command3' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 4
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win', 'command4' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+		$this->assertFalse( $actual );
+
 		// Class 2
 
 		$reflection = new \ReflectionClass( 'CommandFactoryTests_Get_Doc_Comment_2_Command' );
@@ -118,6 +198,23 @@ function testGetDocComment() {
 		$this->assertSame( $expected, $actual );
 		$this->assertFalse( $actual );
 
+		// Class 2 Windows
+
+		$reflection = new \ReflectionClass( 'CommandFactoryTests_Get_Doc_Comment_2_Command_Win' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 1
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_2_Command_Win', 'command1' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+		$this->assertFalse( $actual );
+
 		// Functions
 
 		require __DIR__ . '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/data/commandfactory-doc_comment-function.php';
@@ -147,8 +244,175 @@ function testGetDocComment() {
 		$this->assertSame( $expected, $actual );
 
 		// Restore.
+		putenv( false === $get_doc_comment ? 'WP_CLI_TEST_GET_DOC_COMMENT' : "WP_CLI_TEST_GET_DOC_COMMENT=$get_doc_comment" );
+		putenv( false === $is_windows ? 'WP_CLI_TEST_IS_WINDOWS' : "WP_CLI_TEST_IS_WINDOWS=$is_windows" );
+	}
+
+	function testGetDocCommentWin() {
+		// Save and set test env var.
+		$get_doc_comment = getenv( 'WP_CLI_TEST_GET_DOC_COMMENT' );
+		$is_windows = getenv( 'WP_CLI_TEST_IS_WINDOWS' );
+
+		putenv( 'WP_CLI_TEST_GET_DOC_COMMENT=1' );
+		putenv( 'WP_CLI_TEST_IS_WINDOWS=1' );
+
+		// Make private function accessible.
+		$get_doc_comment = new \ReflectionMethod( 'WP_CLI\Dispatcher\CommandFactory', 'get_doc_comment' );
+		$get_doc_comment->setAccessible( true );
+
+		if ( ! class_exists( 'CommandFactoryTests_Get_Doc_Comment_1_Command', false ) ) {
+			require __DIR__ . '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/data/commandfactory-doc_comment-class.php';
+		}
+		if ( ! class_exists( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win', false ) ) {
+			require __DIR__ . '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/data/commandfactory-doc_comment-class-win.php';
+		}
+
+		// Class 1
+
+		$reflection = new \ReflectionClass( 'CommandFactoryTests_Get_Doc_Comment_1_Command' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 1
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command', 'command1' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 2
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command', 'command2' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 3
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command', 'command3' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 4
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command', 'command4' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+		$this->assertFalse( $actual );
+
+		// Class 1 Windows
+
+		$reflection = new \ReflectionClass( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 1
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win', 'command1' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 2
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win', 'command2' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 3
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win', 'command3' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 4
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_1_Command_Win', 'command4' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+		$this->assertFalse( $actual );
+
+		// Class 2
+
+		$reflection = new \ReflectionClass( 'CommandFactoryTests_Get_Doc_Comment_2_Command' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 1
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_2_Command', 'command1' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+		$this->assertFalse( $actual );
+
+		// Class 2 Windows
+
+		$reflection = new \ReflectionClass( 'CommandFactoryTests_Get_Doc_Comment_2_Command_Win' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Class method 1
+
+		$reflection = new \ReflectionMethod( 'CommandFactoryTests_Get_Doc_Comment_2_Command_Win', 'command1' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+		$this->assertFalse( $actual );
+
+		// Functions
+
+		require __DIR__ . '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/data/commandfactory-doc_comment-function-win.php';
+
+		// Function 1 Windows
+
+		$reflection = new \ReflectionFunction( 'commandfactorytests_get_doc_comment_func_1_win' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Function 2
 
-		putenv( false === $prev_test_get_doc_comment ? 'WP_CLI_TEST_GET_DOC_COMMENT' : "WP_CLI_TEST_GET_DOC_COMMENT=$prev_test_get_doc_comment" );
-		$this->assertTrue( true );
+		$reflection = new \ReflectionFunction( 'commandfactorytests_get_doc_comment_func_2_win' );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Function 3
+
+		$reflection = new \ReflectionFunction( $commandfactorytests_get_doc_comment_func_3_win );
+		$expected = $reflection->getDocComment();
+
+		$actual = $get_doc_comment->invoke( null, $reflection );
+		$this->assertSame( $expected, $actual );
+
+		// Restore.
+		putenv( false === $get_doc_comment ? 'WP_CLI_TEST_GET_DOC_COMMENT' : "WP_CLI_TEST_GET_DOC_COMMENT=$get_doc_comment" );
+		putenv( false === $is_windows ? 'WP_CLI_TEST_IS_WINDOWS' : "WP_CLI_TEST_IS_WINDOWS=$is_windows" );
 	}
 }
diff --git a/tests/test-logging.php b/tests/test-logging.php
index 98604965f2..cd366b73c5 100644
--- a/tests/test-logging.php
+++ b/tests/test-logging.php
@@ -11,7 +11,7 @@ protected function get_runner() {
 	}
 
 	protected function write( $handle, $str ) {
-		echo $str;
+		echo WP_CLI\Utils\denormalize_newlines( $str );
 	}
 }
 
@@ -46,7 +46,7 @@ function testLogEscaping() {
 
 		$message = 'foo%20bar';
 
-		$this->expectOutputString( "Success: $message\n" );
+		$this->expectOutputString( 'Success: ' . $message . PHP_EOL );
 		$logger->success( $message );
 	}
 }
diff --git a/tests/test-utils.php b/tests/test-utils.php
index 8ee3a589fe..20749e8edf 100644
--- a/tests/test-utils.php
+++ b/tests/test-utils.php
@@ -195,4 +195,39 @@ public function testGetHomeDir() {
 		putenv( false === $homedrive ? 'HOMEDRIVE' : "HOME=$homedrive" );
 		putenv( false === $homepath ? 'HOMEPATH' : "HOME=$homepath" );
 	}
+
+	/**
+	 * @dataProvider dataProviderNormalizeNewlines
+	 */
+	public function testNormalizeNewlines( $in, $normalized, $out_win ) {
+		// Save and set test env var.
+		$is_windows = getenv( 'WP_CLI_TEST_IS_WINDOWS' );
+
+		putenv( 'WP_CLI_TEST_IS_WINDOWS=0' );
+
+		$actual = Utils\normalize_newlines( $in );
+		$this->assertSame( $normalized, $actual );
+		$actual = Utils\denormalize_newlines( $normalized );
+		$this->assertSame( $normalized, $actual );
+
+		putenv( 'WP_CLI_TEST_IS_WINDOWS=1' );
+
+		$actual = Utils\normalize_newlines( $in );
+		$this->assertSame( $normalized, $actual );
+		$actual = Utils\denormalize_newlines( $normalized );
+		$this->assertSame( $out_win, $actual );
+		// Test leaves already denormalized alone.
+		$actual = Utils\denormalize_newlines( $out_win );
+		$this->assertSame( $out_win, $actual );
+
+		// Restore.
+		putenv( false === $is_windows ? 'WP_CLI_TEST_IS_WINDOWS' : "WP_CLI_TEST_IS_WINDOWS=$is_windows" );
+	}
+
+	function dataProviderNormalizeNewlines() {
+		return array(
+			array( "blah\nblah\n\nblah\nblah\n\n", "blah\nblah\n\nblah\nblah\n\n", "blah\r\nblah\r\n\r\nblah\r\nblah\r\n\r\n" ),
+			array( "\r\nblah\nblah\r\n\r\nblah\nblah\r\n\n", "\nblah\nblah\n\nblah\nblah\n\n", "\r\nblah\r\nblah\r\n\r\nblah\r\nblah\r\n\r\n" ),
+		);
+	}
 }
diff --git a/utils/make-phar.php b/utils/make-phar.php
index 43561b5cf3..6d555209b6 100644
--- a/utils/make-phar.php
+++ b/utils/make-phar.php
@@ -24,7 +24,7 @@
 list( $args, $assoc_args, $runtime_config ) = $configurator->parse_args( array_slice( $GLOBALS['argv'], 1 ) );
 
 if ( ! isset( $args[0] ) || empty( $args[0] ) ) {
-	echo "usage: php -dphar.readonly=0 $argv[0] <path> [--quiet] [--version=same|patch|minor|major|x.y.z] [--store-version]\n";
+	echo "usage: php -dphar.readonly=0 $argv[0] <path> [--quiet] [--version=same|patch|minor|major|x.y.z] [--store-version]" . PHP_EOL;
 	exit(1);
 }
 
@@ -49,7 +49,7 @@ function add_file( $phar, $path ) {
 	$key = str_replace( WP_CLI_BASE_PATH, '', $path );
 
 	if ( !BE_QUIET )
-		echo "$key - $path\n";
+		echo "$key - $path" . PHP_EOL;
 
 	$phar[ $key ] = file_get_contents( $path );
 }
@@ -58,7 +58,7 @@ function set_file_contents( $phar, $path, $content ) {
 	$key = str_replace( WP_CLI_BASE_PATH, '', $path );
 
 	if ( !BE_QUIET )
-		echo "$key - $path\n";
+		echo "$key - $path" . PHP_EOL;
 
 	$phar[ $key ] = $content;
 }
@@ -179,4 +179,4 @@ function set_file_contents( $phar, $path, $content ) {
 
 $phar->stopBuffering();
 
-echo "Generated " . DEST_PATH . "\n";
+echo "Generated " . DEST_PATH . PHP_EOL;