Roll Observatory packages and add a roll script

packages/package_config/test/parse_write_test.dart

+// Copyright (c) 2015, 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.
+
+library package_config.parse_write_test;
+
+import "package:package_config/packages_file.dart";
+import "package:test/test.dart";
+
+main() {
+  testBase(baseDirString) {
+    var baseDir = Uri.parse(baseDirString);
+    group("${baseDir.scheme} base", () {
+      Uri packagesFile = baseDir.resolve(".packages");
+
+      roundTripTest(String name, Map<String, Uri> map) {
+        group(name, () {
+          test("write with no baseUri", () {
+            var content = writeToString(map).codeUnits;
+            var resultMap = parse(content, packagesFile);
+            expect(resultMap, map);
+          });
+
+          test("write with base directory", () {
+            var content = writeToString(map, baseUri: baseDir).codeUnits;
+            var resultMap = parse(content, packagesFile);
+            expect(resultMap, map);
+          });
+
+          test("write with base .packages file", () {
+            var content = writeToString(map, baseUri: packagesFile).codeUnits;
+            var resultMap = parse(content, packagesFile);
+            expect(resultMap, map);
+          });
+        });
+      }
+      var lowerDir = baseDir.resolve("path3/path4/");
+      var higherDir = baseDir.resolve("../");
+      var parallelDir = baseDir.resolve("../path3/");
+      var rootDir = baseDir.resolve("/");
+      var fileDir = Uri.parse("file:///path1/part2/");
+      var httpDir = Uri.parse("http://example.com/path1/path2/");
+      var otherDir = Uri.parse("other:/path1/path2/");
+
+      roundTripTest("empty", {});
+      roundTripTest("lower directory", {"foo": lowerDir});
+      roundTripTest("higher directory", {"foo": higherDir});
+      roundTripTest("parallel directory", {"foo": parallelDir});
+      roundTripTest("same directory", {"foo": baseDir});
+      roundTripTest("root directory", {"foo": rootDir});
+      roundTripTest("file directory", {"foo": fileDir});
+      roundTripTest("http directory", {"foo": httpDir});
+      roundTripTest("other scheme directory", {"foo": otherDir});
+      roundTripTest("multiple same-type directories",
+                    {"foo": lowerDir, "bar": higherDir, "baz": parallelDir});
+      roundTripTest("multiple scheme directories",
+                    {"foo": fileDir, "bar": httpDir, "baz": otherDir});
+      roundTripTest("multiple scheme directories and mutliple same type",
+                    {"foo": fileDir, "bar": httpDir, "baz": otherDir,
+                     "qux": lowerDir, "hip": higherDir, "dep": parallelDir});
+    });
+  }
+
+  testBase("file:///base1/base2/");
+  testBase("http://example.com/base1/base2/");
+  testBase("other:/base1/base2/");
+
+  // Check that writing adds the comment.
+  test("write preserves comment", () {
+    var comment = "comment line 1\ncomment line 2\ncomment line 3";
+    var result = writeToString({}, comment: comment);
+    // Comment with "# " before each line and "\n" after last.
+    var expectedComment =
+        "# comment line 1\n# comment line 2\n# comment line 3\n";
+    expect(result, startsWith(expectedComment));
+  });
+}
+
+String writeToString(Map map, {Uri baseUri, String comment}) {
+  var buffer = new StringBuffer();
+  write(buffer, map, baseUri: baseUri, comment: comment);
+  return buffer.toString();
+}