Start implementing pub object model. Rudimentary package cache class, and a simple pub command to l…

utils/tests/pub/test_pub.dart

Index: utils/tests/pub/test_pub.dart
diff --git a/utils/tests/pub/test_pub.dart b/utils/tests/pub/test_pub.dart
index c37483de62c768207e008536f7d464befc58a2cf..49b64e88f2767c3d310bce94271b9395a5014107 100644
--- a/utils/tests/pub/test_pub.dart
+++ b/utils/tests/pub/test_pub.dart
@@ -13,59 +13,95 @@
 #import('dart:io');
 
 #import('../../../lib/unittest/unittest.dart');
-#import('../../lib/file_system.dart');
+#import('../../lib/file_system.dart', prefix: 'fs');
+#import('../../pub/io.dart');
 
-void testOutput(String description, List<String> pubArgs, String expected,
-    [int exitCode = 0]) {
+/**
+ * Creates a new [FileDescriptor] with [name] and [contents].
+ */
+FileDescriptor file(String name, String contents) =>
+    new FileDescriptor(name, contents);
+
+/**
+ * Creates a new [DirectoryDescriptor] with [name] and [contents].
+ */
+DirectoryDescriptor dir(String name, [List<Descriptor> contents]) =>
+    new DirectoryDescriptor(name, contents);
+
+void testPub(String description, [List<Descriptor> cache, List<String> args,
+    String output, int exitCode = 0]) {
   asyncTest(description, 1, () {
-    // Find a dart executable we can use to run pub. Uses the one that the
-    // test infrastructure uses.
-    final scriptDir = new File(new Options().script).directorySync().path;
-    final platform = Platform.operatingSystem();
-    final dartBin = joinPaths(scriptDir,
-        '../../../tools/testing/bin/$platform/dart');
-
-    // Find the main pub entrypoint.
-    final pubPath = joinPaths(scriptDir, '../../pub/pub.dart');
-
-    final args = [pubPath];
-    args.addAll(pubArgs);
-
-    final process = new Process.start(dartBin, args);
-    final outStream = new StringInputStream(process.stdout);
-    final output = <String>[];
-    bool processDone = false;
-
-    checkComplete() {
-      if (!outStream.closed) return;
-      if (!processDone) return;
-
-      _validateOutput(expected, output);
-      callbackDone();
+    var createdSandboxDir;
+
+    deleteSandboxIfCreated() {
+      if (createdSandboxDir != null) {
+        deleteDir(createdSandboxDir).then((_) {
+          callbackDone();
+        });
+      } else {
+        callbackDone();
+      }
     }
 
-    process.stderr.pipe(stderr, close: false);
+    final future = _setUpSandbox().chain((sandboxDir) {
+      createdSandboxDir = sandboxDir;
+      return _setUpCache(sandboxDir, cache);
+    }).chain((cacheDir) {
+      if (cacheDir != null) {
+        // TODO(rnystrom): Hack in the cache directory path. Should pass this
+        // in using environment var once #752 is done.
+        args.add('--cachedir=${cacheDir.path}');
+      }
+
+      return _runPub(args);
+    });
+
+    future.then((result) {
+      _validateOutput(output, result.stdout);
 
-    outStream.onLine = () {
-      output.add(outStream.readLine());
-    };
+      Expect.equals(result.stderr.length, 0,
+          'Did not expect any output on stderr, and got:\n' +
+          Strings.join(result.stderr, '\n'));
 
-    outStream.onClosed = checkComplete;
+      Expect.equals(result.exitCode, exitCode,
+          'Pub returned exit code ${result.exitCode}, expected $exitCode.');
 
-    process.onError = (error) {
-      Expect.fail('Failed to run pub: $error');
-      processDone = true;
-    };
+      deleteSandboxIfCreated();
+    });
 
-    process.onExit = (actualExitCode) {
-      Expect.equals(actualExitCode, exitCode,
-          'Pub returned exit code $actualExitCode, expected $exitCode.');
-      processDone = true;
-      checkComplete();
-    };
+    future.handleException((error) {
+      deleteSandboxIfCreated();
+    });
   });
 }
 
+Future<Directory> _setUpSandbox() {
+  return createTempDir('pub-test-sandbox-');
+}
+
+Future _setUpCache(Directory sandboxDir, List<Descriptor> cache) {
+  // No cache.
+  if (cache == null) return new Future.immediate(null);
+
+  return dir('pub-cache', cache).create(sandboxDir);
+}
+
+Future<ProcessResult> _runPub(List<String> pubArgs) {
+  // Find a dart executable we can use to run pub. Uses the one that the
+  // test infrastructure uses.
+  final scriptDir = new File(new Options().script).directorySync().path;
+  final platform = Platform.operatingSystem();
+  final dartBin = join(scriptDir, '../../../tools/testing/bin/$platform/dart');
+
+  // Find the main pub entrypoint.
+  final pubPath = fs.joinPaths(scriptDir, '../../pub/pub.dart');
+
+  final args = [pubPath];
+  args.addAll(pubArgs);
+
+  return runProcess(dartBin, args);
+}
+
 /**
  * Compares the [actual] output from running pub with [expectedText]. Ignores
  * leading and trailing whitespace differences and tries to report the
@@ -104,3 +140,83 @@ void _validateOutput(String expectedText, List<String> actual) {
     Expect.fail(message.toString());
   }
 }
+
+/**
+ * Base class for [FileDescriptor] and [DirectoryDescriptor] so that a
+ * directory can contain a heterogeneous collection of files and
+ * subdirectories.
+ */
+class Descriptor {
+  /**
+   * The short name of this file or directory.
+   */
+  final String name;
+
+  Descriptor(this.name);
+
+  /**
+   * Creates the file or directory within [dir]. Returns a [Future] that is
+   * completed after the creation is done.
+   */
+  abstract Future create(String dir);
+}
+
+/**
+ * Describes a file. These are used both for setting up an expected directory
+ * tree before running a test, and for validating that the file system matches
+ * some expectations after running it.
+ */
+class FileDescriptor extends Descriptor {
+  /**
+   * The text contents of the file.
+   */
+  final String contents;
+
+  FileDescriptor(String name, this.contents) : super(name);
+
+  /**
+   * Creates the file within [dir]. Returns a [Future] that is completed after
+   * the creation is done.
+   */
+  Future<File> create(String dir) {
+    return writeTextFile(join(dir, name), contents);
+  }
+}
+
+/**
+ * Describes a directory and its contents. These are used both for setting up
+ * an expected directory tree before running a test, and for validating that
+ * the file system matches some expectations after running it.
+ */
+class DirectoryDescriptor extends Descriptor {
+  /**
+   * The files and directories contained in this directory.
+   */
+  final List<Descriptor> contents;
+
+  DirectoryDescriptor(String name, this.contents) : super(name);
+
+  /**
+   * Creates the file within [dir]. Returns a [Future] that is completed after
+   * the creation is done.
+   */
+  Future<Directory> create(String parentDir) {
+    final completer = new Completer<Directory>();
+
+    // Create the directory.
+    createDir(join(parentDir, name)).then((dir) {
+      if (contents == null) {
+        completer.complete(dir);
+      } else {
+        // Recursively create all of its children.
+        final childFutures = contents.map((child) => child.create(dir.path));
+        Futures.wait(childFutures).then((_) {
+          // Only complete once all of the children have been created too.
+          completer.complete(dir);
+        });
+      }
+    });
+
+    return completer.future;
+  }
+}