Start extracting common test_config.dart functionality into a utility library.

tools/testing/dart/test_config_utils.dart

Index: tools/testing/dart/test_config_utils.dart
diff --git a/tools/testing/dart/test_config_utils.dart b/tools/testing/dart/test_config_utils.dart
new file mode 100644
index 0000000000000000000000000000000000000000..50219b104217013f4f271ef015d170a263d30d38
--- /dev/null
+++ b/tools/testing/dart/test_config_utils.dart
@@ -0,0 +1,96 @@
+// Copyright (c) 2011, 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("test_config_utils");
+
+/**
+ * TestUtils is a collection of utility methods used to write
+ * test_config.dart scripts for test suites.
+ */
+class TestUtils {
+
+  /**
+   * Get a list of argument lists for the dart shell command.
+   */
+  static List<List<String>> argumentLists(String filename,
+                                          Map optionsFromFile,
+                                          Map configuration) {
+    List args = ["--ignore-unrecognized-flags"];
+    if (configuration["checked"]) {
+      args.add("--enable_type_checks");
+    }
+    if (configuration["component"] == "leg") {
+      args.add("--enable_leg");
+    }
+
+    List<String> dartOptions = optionsFromFile["dartOptions"];
+    args.addAll(dartOptions == null ? [filename] : dartOptions);
+
+    var result = new List<List<String>>();
+    List<List<String>> vmOptionsList = optionsFromFile["vmOptions"];
+    if (vmOptionsList.isEmpty()) {
+      result.add(args);
+    } else {
+      for (var vmOptions in vmOptionsList) {
+        vmOptions.addAll(args);
+        result.add(vmOptions);
+      }
+    }
+
+    return result;
+  }
+
+  /**
+   * Extract test options from the test file itself.
+   */
+  static Map optionsFromFile(String filename, Map configuration) {
+    RegExp testOptionsRegExp = const RegExp(@"// VMOptions=(.*)");
+    RegExp dartOptionsRegExp = const RegExp(@"// DartOptions=(.*)");
+
+    // Read the entire file into a byte buffer and transform it to a
+    // String. This will treat the file as ascii but the only parts
+    // we are interested in will be ascii in any case.
+    File file = new File(filename);
+    file.openSync();
+    List chars = new List(file.lengthSync());
+    var offset = 0;
+    while (offset != chars.length) {
+      offset += file.readListSync(chars, offset, chars.length - offset);
+    }
+    file.closeSync();
+    String contents = new String.fromCharCodes(chars);
+    chars = null;
+
+    // Find the options in the file.
+    List<List> result = new List<List>();
+    List<String> dartOptions;
+    bool isNegative = false;
+
+    Iterable<Match> matches = testOptionsRegExp.allMatches(contents);
+    for (var match in matches) {
+      result.add(match[1].split(' ').filter((e) => e != ''));
+    }
+
+    matches = dartOptionsRegExp.allMatches(contents);
+    for (var match in matches) {
+      if (dartOptions != null) {
+        throw new Exception(
+            'More than one "// DartOptions=" line in test $filename');
+      }
+      dartOptions = match[1].split(' ').filter((e) => e != '');
+    }
+
+    if (contents.contains("@compile-error") ||
+        contents.contains("@runtime-error")) {
+      isNegative = true;
+    } else if (contents.contains("@dynamic-type-error") &&
+               configuration['checked']) {
+      isNegative = true;
+    }
+
+    return { "vmOptions": result,
+             "dartOptions": dartOptions,
+             "isNegative" : isNegative };
+  }
+}