Make a bunch of stuff in pub synchronous.

utils/tests/pub/io_test.dart

Index: utils/tests/pub/io_test.dart
diff --git a/utils/tests/pub/io_test.dart b/utils/tests/pub/io_test.dart
index 94e8a52d871ee15d5e15d0a276b48c4e4199f868..29e970982d0e47a1b12d25f5a1a1348333e424f7 100644
--- a/utils/tests/pub/io_test.dart
+++ b/utils/tests/pub/io_test.dart
@@ -6,16 +6,19 @@ library io_test;
 
 import '../../../pkg/unittest/lib/unittest.dart';
 import '../../pub/io.dart';
+import '../../pub/utils.dart';
 
 main() {
   group('listDir', () {
     test('lists a simple directory non-recursively', () {
       expect(withTempDir((path) {
-        var future = writeTextFile(join(path, 'file1.txt'), '')
-            .then((_) => writeTextFile(join(path, 'file2.txt'), ''))
-            .then((_) => createDir(join(path, 'subdir')))
-            .then((_) => writeTextFile(join(path, 'subdir', 'file3.txt'), ''))
-            .then((_) => listDir(path));
+        var future = defer(() {
+          writeTextFile(join(path, 'file1.txt'), '');
+          writeTextFile(join(path, 'file2.txt'), '');
+          createDir(join(path, 'subdir'));
+          writeTextFile(join(path, 'subdir', 'file3.txt'), '');
+          return listDir(path);
+        });
         expect(future, completion(unorderedEquals([
           join(path, 'file1.txt'),
           join(path, 'file2.txt'),
@@ -27,11 +30,13 @@ main() {
 
     test('lists a simple directory recursively', () {
       expect(withTempDir((path) {
-        var future = writeTextFile(join(path, 'file1.txt'), '')
-            .then((_) => writeTextFile(join(path, 'file2.txt'), ''))
-            .then((_) => createDir(join(path, 'subdir')))
-            .then((_) => writeTextFile(join(path, 'subdir', 'file3.txt'), ''))
-            .then((_) => listDir(path, recursive: true));
+        var future = defer(() {
+          writeTextFile(join(path, 'file1.txt'), '');
+          writeTextFile(join(path, 'file2.txt'), '');
+          createDir(join(path, 'subdir'));
+          writeTextFile(join(path, 'subdir', 'file3.txt'), '');
+          return listDir(path, recursive: true);
+        });
         expect(future, completion(unorderedEquals([
           join(path, 'file1.txt'),
           join(path, 'file2.txt'),
@@ -44,12 +49,14 @@ main() {
 
     test('ignores hidden files by default', () {
       expect(withTempDir((path) {
-        var future = writeTextFile(join(path, 'file1.txt'), '')
-            .then((_) => writeTextFile(join(path, 'file2.txt'), ''))
-            .then((_) => writeTextFile(join(path, '.file3.txt'), ''))
-            .then((_) => createDir(join(path, '.subdir')))
-            .then((_) => writeTextFile(join(path, '.subdir', 'file3.txt'), ''))
-            .then((_) => listDir(path, recursive: true));
+        var future = defer(() {
+          writeTextFile(join(path, 'file1.txt'), '');
+          writeTextFile(join(path, 'file2.txt'), '');
+          writeTextFile(join(path, '.file3.txt'), '');
+          createDir(join(path, '.subdir'));
+          writeTextFile(join(path, '.subdir', 'file3.txt'), '');
+          return listDir(path, recursive: true);
+        });
         expect(future, completion(unorderedEquals([
           join(path, 'file1.txt'),
           join(path, 'file2.txt')
@@ -60,14 +67,14 @@ main() {
 
     test('includes hidden files when told to', () {
       expect(withTempDir((path) {
-        var future = writeTextFile(join(path, 'file1.txt'), '')
-            .then((_) => writeTextFile(join(path, 'file2.txt'), ''))
-            .then((_) => writeTextFile(join(path, '.file3.txt'), ''))
-            .then((_) => createDir(join(path, '.subdir')))
-            .then((_) => writeTextFile(join(path, '.subdir', 'file3.txt'), ''))
-            .then((_) {
-              return listDir(path, recursive: true, includeHiddenFiles: true);
-            });
+        var future = defer(() {
+          writeTextFile(join(path, 'file1.txt'), '');
+          writeTextFile(join(path, 'file2.txt'), '');
+          writeTextFile(join(path, '.file3.txt'), '');
+          createDir(join(path, '.subdir'));
+          writeTextFile(join(path, '.subdir', 'file3.txt'), '');
+          return listDir(path, recursive: true, includeHiddenFiles: true);
+        });
         expect(future, completion(unorderedEquals([
           join(path, 'file1.txt'),
           join(path, 'file2.txt'),
@@ -82,19 +89,18 @@ main() {
     test('returns the unresolved paths for symlinks', () {
       expect(withTempDir((path) {
         var dirToList = join(path, 'dir-to-list');
-        var future = writeTextFile(join(path, 'file1.txt'), '')
-            .then((_) => writeTextFile(join(path, 'file2.txt'), ''))
-            .then((_) => createDir(dirToList))
-            .then((_) {
-              return createSymlink(
-                  join(path, 'file1.txt'),
-                  join(dirToList, 'link1'));
-            }).then((_) => createDir(join(dirToList, 'subdir')))
-            .then((_) {
-              return createSymlink(
+        var future = defer(() {
+          writeTextFile(join(path, 'file1.txt'), '');
+          writeTextFile(join(path, 'file2.txt'), '');
+          createDir(dirToList);
+          return createSymlink(join(path, 'file1.txt'),
+                               join(dirToList, 'link1'));
+        }).then((_) {
+          createDir(join(dirToList, 'subdir'));
+          return createSymlink(
                   join(path, 'file2.txt'),
                   join(dirToList, 'subdir', 'link2'));
-            }).then((_) => listDir(dirToList, recursive: true));
+        }).then((_) => listDir(dirToList, recursive: true));
         expect(future, completion(unorderedEquals([
           join(dirToList, 'link1'),
           join(dirToList, 'subdir'),
@@ -106,9 +112,10 @@ main() {
 
     test('works with recursive symlinks', () {
       expect(withTempDir((path) {
-        var future = writeTextFile(join(path, 'file1.txt'), '')
-            .then((_) => createSymlink(path, join(path, 'linkdir')))
-            .then((_) => listDir(path, recursive: true));
+        var future = defer(() {
+          writeTextFile(join(path, 'file1.txt'), '');
+          return createSymlink(path, join(path, 'linkdir'));
+        }).then((_) => listDir(path, recursive: true));
         expect(future, completion(unorderedEquals([
           join(path, 'file1.txt'),
           join(path, 'linkdir')