Re-apply "Enable use of #import stmts containing relative paths in Dart multitests"

tools/testing/dart/multitest.dart

 // 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("multitest");
 
 #import("dart:io");
+#import("test_suite.dart");
 
 // Multitests are Dart test scripts containing lines of the form
 // " [some dart code] /// [key]: [error type]"
 //
 // For each key in the file, a new test file is made containing all
 // the normal lines of the file, and all of the multitest lines containing
 // that key, in the same order as in the source file.  The new test
 // is expected to fail if there is a non-empty error type listed, of
 // type 'compile-time error', 'runtime error', 'static type error', or
 // 'dynamic type error'.  The type error tests fail only in checked mode.
@@ skipping 52 matching lines @@
   Set<String> validMultitestOutcomes = new Set<String>.from(
       ['compile-time error', 'runtime error',
        'static type error', 'dynamic type error', '']);
 
   List<String> testTemplate = new List<String>();
   testTemplate.add('// Test created from multitest named $filename.');
   // Create the set of multitests, which will have a new test added each
   // time we see a multitest line with a new key.
   Map<String, List<String>> testsAsLines = new Map<String, List<String>>();
 
-  // Matches #import( or #source( followed by " or ' followed by anything
-  // except dart: or /, at the beginning of a line.
-  RegExp relativeImportRegExp =
-      const RegExp('^#(import|source)[(]["\'](?!(dart:|/))');
   int lineCount = 0;
   for (String line in lines) {
     lineCount++;
     if (line.contains('///')) {
       var parts = line.split('///')[1].split(':');
       var key = parts[0].trim();
       var rest = parts[1].trim();
       if (testsAsLines.containsKey(key)) {
         Expect.equals('continued', rest);
         testsAsLines[key].add(line);
       } else {
         (testsAsLines[key] = new List<String>.from(testTemplate)).add(line);
         outcomes[key] = rest;
         if (!validMultitestOutcomes.contains(rest)) {
           Expect.fail("Invalid test directive on line ${lineCount}: $rest ");
         }
       }
     } else {
       testTemplate.add(line);
       for (var test in testsAsLines.getValues()) test.add(line);
     }
-    // Warn if any import or source tags have relative paths.
-    if (relativeImportRegExp.hasMatch(line)) {
-      print('Warning: Multitest cannot contain relative imports:');
-      print('    $filename: $line');
-    }
   }
   // Add the template, with no multitest lines, as a test with key 'none'.
   testsAsLines['none'] = testTemplate;
   outcomes['none'] = '';
 
   // Copy all the tests into the output map tests, as multiline strings.
   for (String key in testsAsLines.getKeys()) {
     tests[key] =
         Strings.join(testsAsLines[key], line_separator) + line_separator;
   }
 }
 
+// Find all relative imports and copy them into the dir that contains
+// the generated tests.
+Set<String> _findAllRelativeImports(String topLibrary) {
+  Set<String> toSearch = new Set<String>.from([topLibrary]);
+  Set<String> foundImports = new HashSet<String>();
+  String pathSep = new Platform().pathSeparator();
+  int end = topLibrary.lastIndexOf(pathSep);
+  String libraryDir = topLibrary.substring(0, end);
+
+  // Matches #import( or #source( followed by " or ' followed by anything
+  // except dart: or /, at the beginning of a line.
+  RegExp relativeImportRegExp =
+      const RegExp('^#(import|source)[(]["\'](?!(dart:|/))([^"\']*)["\']');
+  while (!toSearch.isEmpty()) {
+    var thisPass = toSearch;
+    toSearch = new HashSet<String>();
+    for (String filename in thisPass) {
+      File f = new File(filename);
+      for (String line in f.readAsLinesSync()) {
+        Match match = relativeImportRegExp.firstMatch(line); 
+        if (match != null) {
+          String relativePath = match.group(3);
+          if (foundImports.contains(relativePath)) {
+            continue;
+          }
+          if (relativePath.contains(@'\.\.')) {
+            // This is just for safety reasons, we don't want
+            // to unintentionally clobber files relative to the destination
+            // dir when copying them ove.
+            Expect.fail("relative paths containing .. are not allowed.");
+          }
+          foundImports.add(relativePath);
+          toSearch.add('$libraryDir/$relativePath');
+        }
+      }
+    }
+  }
+  return foundImports;
+}
 
 void DoMultitest(String filename,
                  String outputDir,
                  String testDir,
                  Function doTest(String filename,
                                  bool isNegative,
                                  [bool isNegativeIfChecked,
                                   bool hasFatalTypeErrors,
                                   bool hasRuntimeErrors]),
                  Function multitestDone) {
   // Each new test is a single String value in the Map tests.
   Map<String, String> tests = new Map<String, String>();
   Map<String, String> outcomes = new Map<String, String>();
   ExtractTestsFromMultitest(filename, tests, outcomes);
 
   String directory = CreateMultitestDirectory(outputDir, testDir);
-  String pathSeparator = new Platform().pathSeparator();
-  int start = filename.lastIndexOf(pathSeparator) + 1;
+  Expect.isNotNull(directory);
+  String pathSep = new Platform().pathSeparator();
+  int start = filename.lastIndexOf(pathSep) + 1;
   int end = filename.indexOf('.dart', start);
   String baseFilename = filename.substring(start, end);
+  String sourceDirectory = filename.substring(0, start - 1);
+  Set<String> importsToCopy = _findAllRelativeImports(filename);
+  Directory destDir = new Directory("directory");
+  for (String import in importsToCopy) {
+    File source = new File('$sourceDirectory/$import');
+    var dest = new File('$directory/$import');
+    var basenameStart = import.lastIndexOf('/');
+    if (basenameStart > 0) {
+      // make sure we have a dir for it
+      var importDir = import.substring(0, basenameStart);
+      TestUtils.mkdirRecursive(directory, importDir);
+    }
+    TestUtils.copyFile(source, dest);
+  }
   for (String key in tests.getKeys()) {
     final String filename = '$directory/${baseFilename}_$key.dart';
     final File file = new File(filename);
 
     file.createSync();
     RandomAccessFile openedFile = file.openSync(FileMode.WRITE);
     var bytes = tests[key].charCodes();
     openedFile.writeListSync(bytes, 0, bytes.length);
     openedFile.closeSync();
     var outcome = outcomes[key];
@@ skipping 24 matching lines @@
   var split = testDir.split('/');
   var lastComponent = split.removeLast();
   Expect.isTrue(lastComponent == 'src');
   String path = '${generatedTestDir.path}/${split.last()}';
   Directory dir = new Directory(path);
   if (!dir.existsSync()) {
     dir.createSync();
   }
   return path;
 }