test/formatter_test.dart - dart_style - Git at Google

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 @TestOn("vm")
 library dart_style.test.formatter_test;

 import 'dart:io';
 import 'dart:mirrors';

 import 'package:path/path.dart' as p;
 import 'package:test/test.dart';

 import 'package:dart_style/dart_style.dart';

 void main() {
   testDirectory("comments");
   testDirectory("regression");
   testDirectory("selections");
   testDirectory("splitting");
   testDirectory("whitespace");

   test("throws a FormatterException on failed parse", () {
     var formatter = new DartFormatter();
     expect(() => formatter.format('wat?!'),
         throwsA(new isInstanceOf<FormatterException>()));
   });

   test("FormatterException.message() does not throw", () {
     // This is a regression test for #358 where an error whose position is
     // past the end of the source caused FormatterException to throw.
     try {
       new DartFormatter().format("library");
     } on FormatterException catch (err) {
       var message = err.message();
       expect(message, contains("Could not format"));
     }
   });

   test("FormatterException describes parse errors", () {
     try {
       new DartFormatter().format("""

       var a = some error;

       var b = another one;
       """, uri: "my_file.dart");

       fail("Should throw.");
     } on FormatterException catch (err) {
       var message = err.message();
       expect(message, contains("my_file.dart"));
       expect(message, contains("line 2"));
       expect(message, contains("line 4"));
     }
   });

   test("adds newline to unit", () {
     expect(new DartFormatter().format("var x = 1;"), equals("var x = 1;\n"));
   });

   test("adds newline to unit after trailing comment", () {
     expect(new DartFormatter().format("library foo; //zamm"),
         equals("library foo; //zamm\n"));
   });

   test("removes extra newlines", () {
     expect(
         new DartFormatter().format("var x = 1;\n\n\n"), equals("var x = 1;\n"));
   });

   test("does not add newline to statement", () {
     expect(new DartFormatter().formatStatement("var x = 1;"),
         equals("var x = 1;"));
   });

   test("fails if anything is after the statement", () {
     try {
       new DartFormatter().formatStatement("var x = 1;;");

       fail("Should throw.");
     } on FormatterException catch (ex) {
       expect(ex.errors.length, equals(1));
       expect(ex.errors.first.offset, equals(10));
     }
   });

   test('preserves initial indent', () {
     var formatter = new DartFormatter(indent: 3);
     expect(
         formatter.formatStatement('if (foo) {bar;}'),
         equals('   if (foo) {\n'
             '     bar;\n'
             '   }'));
   });

   group("line endings", () {
     test("uses given line ending", () {
       // Use zero width no-break space character as the line ending. We have
       // to use a whitespace character for the line ending as the formatter
       // will throw an error if it accidentally makes non-whitespace changes
       // as will occur
       var lineEnding = "\t";
       expect(new DartFormatter(lineEnding: lineEnding).format("var i = 1;"),
           equals("var i = 1;\t"));
     });

     test('infers \\r\\n if the first newline uses that', () {
       expect(new DartFormatter().format("var\r\ni\n=\n1;\n"),
           equals("var i = 1;\r\n"));
     });

     test('infers \\n if the first newline uses that', () {
       expect(new DartFormatter().format("var\ni\r\n=\r\n1;\r\n"),
           equals("var i = 1;\n"));
     });

     test('defaults to \\n if there are no newlines', () {
       expect(new DartFormatter().format("var i =1;"), equals("var i = 1;\n"));
     });

     test('handles Windows line endings in multiline strings', () {
       expect(
           new DartFormatter(lineEnding: "\r\n").formatStatement('  """first\r\n'
               'second\r\n'
               'third"""  ;'),
           equals('"""first\r\n'
               'second\r\n'
               'third""";'));
     });
   });

   test('throws an UnexpectedOutputException on non-whitespace changes', () {
     // Use an invalid line ending character to ensure the formatter will
     // attempt to make non-whitespace changes.
     var formatter = new DartFormatter(lineEnding: '%');
     expect(() => formatter.format("var i = 1;"),
         throwsA(new isInstanceOf<UnexpectedOutputException>()));
   });
 }

 /// Run tests defined in "*.unit" and "*.stmt" files inside directory [name].
 void testDirectory(String name) {
   var indentPattern = new RegExp(r"^\(indent (\d+)\)\s*");

   // Locate the "test" directory. Use mirrors so that this works with the test
   // package, which loads this suite into an isolate.
   var testDir = p.dirname(currentMirrorSystem()
       .findLibrary(#dart_style.test.formatter_test)
       .uri
       .toFilePath());

   var entries = new Directory(p.join(testDir, name))
       .listSync(recursive: true, followLinks: false);
   for (var entry in entries) {
     if (!entry.path.endsWith(".stmt") && !entry.path.endsWith(".unit")) {
       continue;
     }

     group("$name ${p.basename(entry.path)}", () {
       // Explicitly create a File, in case the entry is a Link.
       var lines = new File(entry.path).readAsLinesSync();

       // The first line may have a "|" to indicate the page width.
       var pageWidth;
       if (lines[0].endsWith("|")) {
         pageWidth = lines[0].indexOf("|");
         lines = lines.skip(1).toList();
       }

       var i = 0;
       while (i < lines.length) {
         var description = lines[i++].replaceAll(">>>", "").trim();

         // Let the test specify a leading indentation. This is handy for
         // regression tests which often come from a chunk of nested code.
         var leadingIndent = 0;
         var indentMatch = indentPattern.firstMatch(description);
         if (indentMatch != null) {
           leadingIndent = int.parse(indentMatch[1]);
           description = description.substring(indentMatch.end);
         }

         if (description == "") {
           description = "line ${i + 1}";
         } else {
           description = "line ${i + 1}: $description";
         }

         var input = "";
         while (!lines[i].startsWith("<<<")) {
           input += lines[i++] + "\n";
         }

         var expectedOutput = "";
         while (++i < lines.length && !lines[i].startsWith(">>>")) {
           expectedOutput += lines[i] + "\n";
         }

         // TODO(rnystrom): Stop skipping these tests when possible.
         if (description.contains("(skip:")) {
           print("skipping $description");
           continue;
         }

         test(description, () {
           var isCompilationUnit = p.extension(entry.path) == ".unit";

           var inputCode =
               _extractSelection(input, isCompilationUnit: isCompilationUnit);

           var expected = _extractSelection(expectedOutput,
               isCompilationUnit: isCompilationUnit);

           var formatter =
               new DartFormatter(pageWidth: pageWidth, indent: leadingIndent);

           var actual = formatter.formatSource(inputCode);

           // The test files always put a newline at the end of the expectation.
           // Statements from the formatter (correctly) don't have that, so add
           // one to line up with the expected result.
           var actualText = actual.text;
           if (!isCompilationUnit) actualText += "\n";

           // Fail with an explicit message because it's easier to read than
           // the matcher output.
           if (actualText != expected.text) {
             fail("Formatting did not match expectation. Expected:\n"
                 "${expected.text}\nActual:\n$actualText");
           }

           expect(actual.selectionStart, equals(expected.selectionStart));
           expect(actual.selectionLength, equals(expected.selectionLength));
         });
       }
     });
   }
 }

 /// Given a source string that contains ‹ and › to indicate a selection, returns
 /// a [SourceCode] with the text (with the selection markers removed) and the
 /// correct selection range.
 SourceCode _extractSelection(String source, {bool isCompilationUnit: false}) {
   var start = source.indexOf("‹");
   source = source.replaceAll("‹", "");

   var end = source.indexOf("›");
   source = source.replaceAll("›", "");

   return new SourceCode(source,
       isCompilationUnit: isCompilationUnit,
       selectionStart: start == -1 ? null : start,
       selectionLength: end == -1 ? null : end - start);
 }
	// Copyright (c) 2014, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	@TestOn("vm")
	library dart_style.test.formatter_test;

	import 'dart:io';
	import 'dart:mirrors';

	import 'package:path/path.dart' as p;
	import 'package:test/test.dart';

	import 'package:dart_style/dart_style.dart';

	void main() {
	testDirectory("comments");
	testDirectory("regression");
	testDirectory("selections");
	testDirectory("splitting");
	testDirectory("whitespace");

	test("throws a FormatterException on failed parse", () {
	var formatter = new DartFormatter();
	expect(() => formatter.format('wat?!'),
	throwsA(new isInstanceOf<FormatterException>()));
	});

	test("FormatterException.message() does not throw", () {
	// This is a regression test for #358 where an error whose position is
	// past the end of the source caused FormatterException to throw.
	try {
	new DartFormatter().format("library");
	} on FormatterException catch (err) {
	var message = err.message();
	expect(message, contains("Could not format"));
	}
	});

	test("FormatterException describes parse errors", () {
	try {
	new DartFormatter().format("""

	var a = some error;

	var b = another one;
	""", uri: "my_file.dart");

	fail("Should throw.");
	} on FormatterException catch (err) {
	var message = err.message();
	expect(message, contains("my_file.dart"));
	expect(message, contains("line 2"));
	expect(message, contains("line 4"));
	}
	});

	test("adds newline to unit", () {
	expect(new DartFormatter().format("var x = 1;"), equals("var x = 1;\n"));
	});

	test("adds newline to unit after trailing comment", () {
	expect(new DartFormatter().format("library foo; //zamm"),
	equals("library foo; //zamm\n"));
	});

	test("removes extra newlines", () {
	expect(
	new DartFormatter().format("var x = 1;\n\n\n"), equals("var x = 1;\n"));
	});

	test("does not add newline to statement", () {
	expect(new DartFormatter().formatStatement("var x = 1;"),
	equals("var x = 1;"));
	});

	test("fails if anything is after the statement", () {
	try {
	new DartFormatter().formatStatement("var x = 1;;");

	fail("Should throw.");
	} on FormatterException catch (ex) {
	expect(ex.errors.length, equals(1));
	expect(ex.errors.first.offset, equals(10));
	}
	});

	test('preserves initial indent', () {
	var formatter = new DartFormatter(indent: 3);
	expect(
	formatter.formatStatement('if (foo) {bar;}'),
	equals(' if (foo) {\n'
	' bar;\n'
	' }'));
	});

	group("line endings", () {
	test("uses given line ending", () {
	// Use zero width no-break space character as the line ending. We have
	// to use a whitespace character for the line ending as the formatter
	// will throw an error if it accidentally makes non-whitespace changes
	// as will occur
	var lineEnding = "\t";
	expect(new DartFormatter(lineEnding: lineEnding).format("var i = 1;"),
	equals("var i = 1;\t"));
	});

	test('infers \\r\\n if the first newline uses that', () {
	expect(new DartFormatter().format("var\r\ni\n=\n1;\n"),
	equals("var i = 1;\r\n"));
	});

	test('infers \\n if the first newline uses that', () {
	expect(new DartFormatter().format("var\ni\r\n=\r\n1;\r\n"),
	equals("var i = 1;\n"));
	});

	test('defaults to \\n if there are no newlines', () {
	expect(new DartFormatter().format("var i =1;"), equals("var i = 1;\n"));
	});

	test('handles Windows line endings in multiline strings', () {
	expect(
	new DartFormatter(lineEnding: "\r\n").formatStatement(' """first\r\n'
	'second\r\n'
	'third""" ;'),
	equals('"""first\r\n'
	'second\r\n'
	'third""";'));
	});
	});

	test('throws an UnexpectedOutputException on non-whitespace changes', () {
	// Use an invalid line ending character to ensure the formatter will
	// attempt to make non-whitespace changes.
	var formatter = new DartFormatter(lineEnding: '%');
	expect(() => formatter.format("var i = 1;"),
	throwsA(new isInstanceOf<UnexpectedOutputException>()));
	});
	}

	/// Run tests defined in ".unit" and ".stmt" files inside directory [name].
	void testDirectory(String name) {
	var indentPattern = new RegExp(r"^\(indent (\d+)\)\s*");

	// Locate the "test" directory. Use mirrors so that this works with the test
	// package, which loads this suite into an isolate.
	var testDir = p.dirname(currentMirrorSystem()
	.findLibrary(#dart_style.test.formatter_test)
	.uri
	.toFilePath());

	var entries = new Directory(p.join(testDir, name))
	.listSync(recursive: true, followLinks: false);
	for (var entry in entries) {
	if (!entry.path.endsWith(".stmt") && !entry.path.endsWith(".unit")) {
	continue;
	}

	group("$name ${p.basename(entry.path)}", () {
	// Explicitly create a File, in case the entry is a Link.
	var lines = new File(entry.path).readAsLinesSync();

	// The first line may have a "\|" to indicate the page width.
	var pageWidth;
	if (lines[0].endsWith("\|")) {
	pageWidth = lines[0].indexOf("\|");
	lines = lines.skip(1).toList();
	}

	var i = 0;
	while (i < lines.length) {
	var description = lines[i++].replaceAll(">>>", "").trim();

	// Let the test specify a leading indentation. This is handy for
	// regression tests which often come from a chunk of nested code.
	var leadingIndent = 0;
	var indentMatch = indentPattern.firstMatch(description);
	if (indentMatch != null) {
	leadingIndent = int.parse(indentMatch[1]);
	description = description.substring(indentMatch.end);
	}

	if (description == "") {
	description = "line ${i + 1}";
	} else {
	description = "line ${i + 1}: $description";
	}

	var input = "";
	while (!lines[i].startsWith("<<<")) {
	input += lines[i++] + "\n";
	}

	var expectedOutput = "";
	while (++i < lines.length && !lines[i].startsWith(">>>")) {
	expectedOutput += lines[i] + "\n";
	}

	// TODO(rnystrom): Stop skipping these tests when possible.
	if (description.contains("(skip:")) {
	print("skipping $description");
	continue;
	}

	test(description, () {
	var isCompilationUnit = p.extension(entry.path) == ".unit";

	var inputCode =
	_extractSelection(input, isCompilationUnit: isCompilationUnit);

	var expected = _extractSelection(expectedOutput,
	isCompilationUnit: isCompilationUnit);

	var formatter =
	new DartFormatter(pageWidth: pageWidth, indent: leadingIndent);

	var actual = formatter.formatSource(inputCode);

	// The test files always put a newline at the end of the expectation.
	// Statements from the formatter (correctly) don't have that, so add
	// one to line up with the expected result.
	var actualText = actual.text;
	if (!isCompilationUnit) actualText += "\n";

	// Fail with an explicit message because it's easier to read than
	// the matcher output.
	if (actualText != expected.text) {
	fail("Formatting did not match expectation. Expected:\n"
	"${expected.text}\nActual:\n$actualText");
	}

	expect(actual.selectionStart, equals(expected.selectionStart));
	expect(actual.selectionLength, equals(expected.selectionLength));
	});
	}
	});
	}
	}

	/// Given a source string that contains ‹ and › to indicate a selection, returns
	/// a [SourceCode] with the text (with the selection markers removed) and the
	/// correct selection range.
	SourceCode _extractSelection(String source, {bool isCompilationUnit: false}) {
	var start = source.indexOf("‹");
	source = source.replaceAll("‹", "");

	var end = source.indexOf("›");
	source = source.replaceAll("›", "");

	return new SourceCode(source,
	isCompilationUnit: isCompilationUnit,
	selectionStart: start == -1 ? null : start,
	selectionLength: end == -1 ? null : end - start);
	}