Add support for specifying SDK version constraints in pubspecs.

These constraints don't currently do anything, but these patch
gets them being parsed by pub.

Review URL: https://codereview.chromium.org//12038038

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@17477 260f80e4-7a28-3924-810f-c04153c831b5

utils/pub/pubspec.dart

@@ -22,11 +22,14 @@ class Pubspec {
   /// The packages this package depends on.
   final List<PackageRef> dependencies;
 
+  /// The environment-related metadata.
+  final PubspecEnvironment environment;
+
   /// All pubspec fields. This includes the fields from which other properties
   /// are derived.
   final Map<String, Object> fields;
 
-  Pubspec(this.name, this.version, this.dependencies,
+  Pubspec(this.name, this.version, this.dependencies, this.environment,
       [Map<String, Object> fields])
     : this.fields = fields == null ? {} : fields;
 
@@ -34,9 +37,10 @@ class Pubspec {
     : name = null,
       version = Version.none,
       dependencies = <PackageRef>[],
+      environment = new PubspecEnvironment(),
       fields = {};
 
-  /// Whether or not the pubspec has no contents. 
+  /// Whether or not the pubspec has no contents.
   bool get isEmpty =>
     name == null && version == Version.none && dependencies.isEmpty;
 
@@ -70,6 +74,26 @@ class Pubspec {
     var dependencies = _parseDependencies(sources,
         parsedPubspec['dependencies']);
 
+    var environmentYaml = parsedPubspec['environment'];
+    var sdkConstraint = VersionConstraint.any;
+    if (environmentYaml != null) {
+      if (environmentYaml is! Map) {
+        throw new FormatException(
+            'The pubspec "environment" field should be a map, but was '
+            '"$environmentYaml".');
+      }
+
+      var sdkYaml = environmentYaml['sdk'];
+      if (sdkYaml is! String) {
+        throw new FormatException(
+            'The "sdk" field of "environment" should be a string, but was '
+            '"$sdkYaml".');
+      }
+
+      sdkConstraint = new VersionConstraint.parse(sdkYaml);
+    }
+    var environment = new PubspecEnvironment(sdkConstraint);
+
     // Even though the pub app itself doesn't use these fields, we validate
     // them here so that users find errors early before they try to upload to
     // the server:
@@ -123,7 +147,7 @@ class Pubspec {
       }
     }
 
-    return new Pubspec(name, version, dependencies, parsedPubspec);
+    return new Pubspec(name, version, dependencies, environment, parsedPubspec);
   }
 }
 
@@ -181,3 +205,14 @@ List<PackageRef> _parseDependencies(SourceRegistry sources, yaml) {
 
   return dependencies;
 }
+
+/// The environment-related metadata in the pubspec. Corresponds to the data
+/// under the "environment:" key in the pubspec.
+class PubspecEnvironment {
+  /// The version constraint specifying which SDK versions this package works
+  /// with.
+  final VersionConstraint sdkVersion;
+
+  PubspecEnvironment([VersionConstraint sdk])
+      : sdkVersion = sdk != null ? sdk : VersionConstraint.any;
+}

utils/pub/sdk_source.dart

@@ -25,7 +25,8 @@ class SdkSource extends Source {
       return Package.load(id.name, packageDir, systemCache.sources);
     }).then((package) {
       // Ignore the pubspec's version, and use the SDK's.
-      return new Pubspec(id.name, sdk.version, package.pubspec.dependencies);
+      return new Pubspec(id.name, sdk.version, package.pubspec.dependencies,
+          package.pubspec.environment);
     });
   }
 

utils/pub/version.dart

@@ -110,7 +110,9 @@ class Version implements Comparable, VersionConstraint {
     if (other is VersionRange) return other.intersect(this);
 
     // Intersecting two versions only works if they are the same.
-    if (other is Version) return this == other ? this : const _EmptyVersion();
+    if (other is Version) {
+      return this == other ? this : VersionConstraint.empty;
+    }
 
     throw new ArgumentError(
         'Unknown VersionConstraint type $other.');
@@ -206,8 +208,11 @@ class Version implements Comparable, VersionConstraint {
 /// version that is "2.0.0" or greater. Version objects themselves implement
 /// this to match a specific version.
 abstract class VersionConstraint {
+  /// A [VersionConstraint] that allows all versions.
+  static VersionConstraint any = new VersionRange();
+
   /// A [VersionConstraint] that allows no versions: i.e. the empty set.
-  factory VersionConstraint.empty() => const _EmptyVersion();
+  static VersionConstraint empty = const _EmptyVersion();
 
   /// Parses a version constraint. This string is a space-separated series of
   /// version parts. Each part can be one of:
@@ -333,7 +338,9 @@ class VersionRange implements VersionConstraint {
     if (other.isEmpty) return other;
 
     // A range and a Version just yields the version if it's in the range.
-    if (other is Version) return allows(other) ? other : const _EmptyVersion();
+    if (other is Version) {
+      return allows(other) ? other : VersionConstraint.empty;
+    }
 
     if (other is VersionRange) {
       // Intersect the two ranges.
@@ -373,13 +380,13 @@ class VersionRange implements VersionConstraint {
         if (intersectIncludeMin && intersectIncludeMax) return intersectMin;
 
         // Otherwise, no versions.
-        return const _EmptyVersion();
+        return VersionConstraint.empty;
       }
 
       if (intersectMin != null && intersectMax != null &&
           intersectMin > intersectMax) {
         // Non-overlapping ranges, so empty.
-        return const _EmptyVersion();
+        return VersionConstraint.empty;
       }
 
       // If we got here, there is an actual range.

utils/tests/pub/command_line_config.dart

@@ -17,6 +17,7 @@ const _NONE = '\u001b[0m';
 /// Pretty Unicode characters!
 const _CHECKBOX = '\u2713';
 const _BALLOT_X = '\u2717';
+const _LAMBDA   = '\u03bb';
 
 /// A custom unittest configuration for running the pub tests from the
 /// command-line and generating human-friendly output.
@@ -70,14 +71,10 @@ class CommandLineConfiguration extends Configuration {
     if (stackTrace == null || stackTrace == '') return;
 
     // Parse out each stack entry.
-    var regexp = new RegExp(r'#\d+\s+(.*) \(file:///([^)]+)\)');
     var stack = [];
     for (var line in stackTrace.split('\n')) {
       if (line.trim() == '') continue;
-
-      var match = regexp.firstMatch(line);
-      if (match == null) throw "Couldn't clean up stack trace line '$line'.";
-      stack.add(new Pair(match[2], match[1]));
+      stack.add(new _StackFrame(line));
     }
 
     if (stack.length == 0) return;
@@ -86,10 +83,12 @@ class CommandLineConfiguration extends Configuration {
     var common = 0;
     while (true) {
       var matching = true;
-      // TODO(bob): Handle empty stack.
-      var c = stack[0].first[common];
-      for (var pair in stack) {
-        if (pair.first.length <= common || pair.first[common] != c) {
+      var c;
+      for (var frame in stack) {
+        if (frame.isCore) continue;
+        if (c == null) c = frame.library[common];
+
+        if (frame.library.length <= common || frame.library[common] != c) {
           matching = false;
           break;
         }
@@ -101,19 +100,18 @@ class CommandLineConfiguration extends Configuration {
 
     // Remove them.
     if (common > 0) {
-      for (var pair in stack) {
-        pair.first = pair.first.substring(common);
+      for (var frame in stack) {
+        if (frame.isCore) continue;
+        frame.library = frame.library.substring(common);
       }
     }
 
     // Figure out the longest path so we know how much to pad.
-    int longest = stack.mappedBy((pair) => pair.first.length).max();
+    int longest = stack.mappedBy((frame) => frame.location.length).max();
 
     // Print out the stack trace nicely formatted.
-    for (var pair in stack) {
-      var path = pair.first;
-      path = path.replaceFirst(':', ' ');
-      print('  ${_padLeft(path, longest)}  ${pair.last}');
+    for (var frame in stack) {
+      print('  ${_padLeft(frame.location, longest)}  ${frame.member}');
     }
 
     print('');
@@ -137,3 +135,44 @@ class CommandLineConfiguration extends Configuration {
     return Strings.join(str.split("\n").mappedBy((line) => "  $line"), "\n");
   }
 }
+
+class _StackFrame {
+  static final fileRegExp = new RegExp(
+      r'#\d+\s+(.*) \((file:///.+):(\d+):(\d+)\)');
+  static final coreRegExp = new RegExp(r'#\d+\s+(.*) \((.+):(\d+):(\d+)\)');
+
+  /// If `true`, then this stack frame is for a library built into Dart and
+  /// not a regular file path.
+  final bool isCore;
+
+  /// The path to the library or the library name if a core library.
+  String library;
+
+  /// The line number.
+  final String line;
+
+  /// The column number.
+  final String column;
+
+  /// The member where the error occurred.
+  final String member;
+
+  /// A formatted description of the code location.
+  String get location => '$library $line:$column';
+
+  _StackFrame._(this.isCore, this.library, this.line, this.column, this.member);
+
+  factory _StackFrame(String text) {
+    var match = fileRegExp.firstMatch(text);
+    var isCore = false;
+
+    if (match == null) {
+      match = coreRegExp.firstMatch(text);
+      if (match == null) throw "Couldn't parse stack trace line '$text'.";
+      isCore = true;
+    }
+
+    var member = match[1].replaceAll("<anonymous closure>", _LAMBDA);
+    return new _StackFrame._(isCore, match[2], match[3], match[4], member);
+  }
+}

utils/tests/pub/pubspec_test.dart

@@ -5,6 +5,7 @@
 library pubspec_test;
 
 import '../../../pkg/unittest/lib/unittest.dart';
+import 'test_pub.dart';
 import '../../pub/pubspec.dart';
 import '../../pub/source.dart';
 import '../../pub/source_registry.dart';
@@ -112,6 +113,49 @@ dependencies:
         expect(pubspec.version, equals(Version.none));
         expect(pubspec.dependencies, isEmpty);
       });
+
+      group("environment", () {
+        test("defaults to any SDK constraint if environment is omitted", () {
+          var pubspec = new Pubspec.parse('', sources);
+          expect(pubspec.environment.sdkVersion, equals(VersionConstraint.any));
+        });
+
+        test("allows an empty environment map", () {
+          var pubspec = new Pubspec.parse('''
+environment:
+''', sources);
+          expect(pubspec.environment.sdkVersion, equals(VersionConstraint.any));
+        });
+
+        test("throws if the environment value isn't a map", () {
+          expectFormatError('''
+environment: []
+''');
+        });
+
+        test("allows a version constraint for the sdk", () {
+          var pubspec = new Pubspec.parse('''
+environment:
+  sdk: ">=1.2.3 <2.3.4"
+''', sources);
+          expect(pubspec.environment.sdkVersion,
+              equals(new VersionConstraint.parse(">=1.2.3 <2.3.4")));
+        });
+
+        test("throws if the sdk isn't a string", () {
+          expectFormatError('''
+environment:
+  sdk: []
+''');
+        });
+
+        test("throws if the sdk isn't a valid version constraint", () {
+          expectFormatError('''
+environment:
+  sdk: "oopies"
+''');
+        });
+      });
     });
   });
 }

utils/tests/pub/version_solver_test.dart

@@ -495,7 +495,8 @@ class MockSource extends Source {
     });
 
     var pubspec = new Pubspec(
-        description, new Version.parse(version), dependencies);
+        description, new Version.parse(version), dependencies,
+        new PubspecEnvironment());
     return new Package.inMemory(pubspec);
   }
 

utils/tests/pub/version_test.dart

@@ -5,6 +5,7 @@
 library version_test;
 
 import '../../../pkg/unittest/lib/unittest.dart';
+import 'test_pub.dart';
 import '../../pub/utils.dart';
 import '../../pub/version.dart';
 
@@ -302,8 +303,20 @@ main() {
   });
 
   group('VersionConstraint', () {
+    test('any', () {
+      expect(VersionConstraint.any.isAny, isTrue);
+      expect(VersionConstraint.any, allows([
+        new Version.parse('0.0.0-blah'),
+        new Version.parse('1.2.3'),
+        new Version.parse('12345.678.90')]));
+    });
+
     test('empty', () {
-      expect(new VersionConstraint.empty().isEmpty, isTrue);
+      expect(VersionConstraint.empty.isEmpty, isTrue);
+      expect(VersionConstraint.empty, doesNotAllow([
+        new Version.parse('0.0.0-blah'),
+        new Version.parse('1.2.3'),
+        new Version.parse('12345.678.90')]));
     });
 
     group('parse()', () {