Triage more solver tests

lib/src/global_packages.dart

@@ -24,6 +24,7 @@ import 'package_name.dart';
 import 'pubspec.dart';
 import 'sdk.dart' as sdk;
 import 'solver.dart';
+import 'solver/incompatibility_cause.dart';
 import 'source/cached.dart';
 import 'source/git.dart';
 import 'source/hosted.dart';
@@ -175,7 +176,18 @@ class GlobalPackages {
     //
     // TODO(nweiz): If this produces a SolveFailure that's caused by [dep] not
     // being available, report that as a [dataError].
-    var result = await resolveVersions(SolveType.GET, cache, root);
+    SolveResult result;
+    try {
+      result = await resolveVersions(SolveType.GET, cache, root);
+    } on SolveFailure catch (error) {
+      for (var incompatibility
+          in error.incompatibility.externalIncompatibilities) {
+        if (incompatibility.cause != IncompatibilityCause.noVersions) continue;
+        if (incompatibility.terms.single.package.name != dep.name) continue;
+        dataError(error.toString());
+      }
+      rethrow;
+    }
 
     result.showReport(SolveType.GET);
 

lib/src/solver/failure.dart

@@ -27,7 +27,8 @@ class SolveFailure implements ApplicationException {
   /// If multiple [PackageNotFoundException]s caused the error, it's undefined
   /// which one is returned.
   PackageNotFoundException get packageNotFound {
-    for (var cause in incompatibility.externalCauses) {
+    for (var incompatibility in incompatibility.externalIncompatibilities) {
+      var cause = incompatibility.cause;
       if (cause is PackageNotFoundCause) return cause.exception;
     }
     return null;
@@ -94,7 +95,8 @@ class _Writer {
     var hasFlutterCause = false;
     var hasDartSdkCause = false;
     var hasFlutterSdkCause = false;
-    for (var cause in _root.externalCauses) {
+    for (var incompatibility in _root.externalIncompatibilities) {
+      var cause = incompatibility.cause;
       if (cause.isFlutter) hasFlutterCause = true;
       if (cause is SdkCause) {
         if (cause.isFlutter) {

lib/src/solver/incompatibility.dart

@@ -24,15 +24,15 @@ class Incompatibility {
   bool get isFailure =>
       terms.isEmpty || (terms.length == 1 && terms.first.package.isRoot);
 
-  /// Returns the causes of all external incompatibilities in this
-  /// incompatibility's derivation graph.
-  Iterable<IncompatibilityCause> get externalCauses sync* {
+  /// Returns all external incompatibilities in this incompatibility's
+  /// derivation graph.
+  Iterable<Incompatibility> get externalIncompatibilities sync* {
     if (cause is ConflictCause) {
       var cause = this.cause as ConflictCause;
-      yield* cause.conflict.externalCauses;
-      yield* cause.other.externalCauses;
+      yield* cause.conflict.externalIncompatibilities;
+      yield* cause.other.externalIncompatibilities;
     } else {
-      yield cause;
+      yield this;
     }
   }
 

lib/src/solver/package_lister.dart

@@ -285,7 +285,7 @@ class PackageLister {
         ? _matchesFlutterSdkConstraint(pubspec)
         : _matchesDartSdkConstraint(pubspec);
 
-    if (allowsSdk(await _source.describe(versions[index]))) return null;
+    if (allowsSdk(await _describeSafe(versions[index]))) return null;
 
     var bounds = await _findBounds(index, (pubspec) => !allowsSdk(pubspec));
     var incompatibleVersions = new VersionRange(
@@ -300,7 +300,7 @@ class PackageLister {
     var sdkConstraint = await foldAsync(
         slice(versions, bounds.first, bounds.last + 1), VersionConstraint.empty,
         (previous, version) async {
-      var pubspec = await _source.describe(version);
+      var pubspec = await _describeSafe(version);
       return previous.union(
           flutter ? pubspec.flutterSdkConstraint : pubspec.dartSdkConstraint);
     });
@@ -320,13 +320,13 @@ class PackageLister {
 
     var first = start - 1;
     while (first > 0) {
-      if (!match(await _source.describe(versions[first]))) break;
+      if (!match(await _describeSafe(versions[first]))) break;
       first--;
     }
 
     var last = start + 1;
     while (last < versions.length) {
-      if (!match(await _source.describe(versions[last]))) break;
+      if (!match(await _describeSafe(versions[last]))) break;
       last++;
     }
 
@@ -350,7 +350,7 @@ class PackageLister {
     for (var id in upper
         ? versions.skip(index + 1)
         : versions.reversed.skip(versions.length - index)) {
-      var pubspec = await _source.describe(id);
+      var pubspec = await _describeSafe(id);
 
       // The upper bound is exclusive and so is the first package with a
       // different dependency. The lower bound is inclusive, and so is the last
@@ -381,6 +381,19 @@ class PackageLister {
     return bounds;
   }
 
+  /// Returns the pubspec for [id], or an empty pubpsec matching [id] if the
+  /// real pubspec for [id] fails to load for any reason.
+  ///
+  /// This makes the bounds-finding logic resilient to broken pubspecs while
+  /// keeping the actual error handling in a central location.
+  Future<Pubspec> _describeSafe(PackageId id) async {
+    try {
+      return await _source.describe(id);
+    } catch (_) {
+      return new Pubspec(id.name, version: id.version);
+    }
+  }
+
   /// Returns whether [pubspec]'s Dart SDK constraint matches the current Dart
   /// SDK version.
   bool _matchesDartSdkConstraint(Pubspec pubspec) =>

test/get/path/shared_dependency_test.dart

@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE d.file.
 
-@Skip()
-
 import 'package:test/test.dart';
 
 import 'package:path/path.dart' as path;
@@ -73,38 +71,4 @@ main() {
     await d.appPackagesFile(
         {"foo": "../foo", "bar": "../bar", "shared": "../shared"}).validate();
   });
-
-  test("shared dependency with absolute and relative path", () async {
-    await d.dir("shared",
-        [d.libDir("shared"), d.libPubspec("shared", "0.0.1")]).create();
-
-    await d.dir("foo", [
-      d.libDir("foo"),
-      d.libPubspec("foo", "0.0.1", deps: {
-        "shared": {"path": "../shared"}
-      })
-    ]).create();
-
-    await d.dir("bar", [
-      d.libDir("bar"),
-      d.libPubspec("bar", "0.0.1", deps: {
-        "shared": {"path": path.join(d.sandbox, "shared")}
-      })
-    ]).create();
-
-    await d.dir(appPath, [
-      d.appPubspec({
-        "foo": {"path": "../foo"},
-        "bar": {"path": "../bar"}
-      })
-    ]).create();
-
-    await pubGet();
-
-    await d.appPackagesFile({
-      "foo": "../foo",
-      "bar": "../bar",
-      "shared": path.join(d.sandbox, "shared")
-    }).validate();
-  });
 }

test/global/activate/empty_constraint_test.dart

@@ -2,8 +2,6 @@
 // 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.
 
-@Skip()
-
 import 'package:test/test.dart';
 
 import 'package:pub/src/exit_codes.dart' as exit_codes;
@@ -19,9 +17,10 @@ main() {
 
     await runPub(
         args: ["global", "activate", "foo", ">1.1.0"],
-        error: """
-            Package foo has no versions that match >1.1.0 derived from:
-            - pub global activate depends on version >1.1.0""",
+        error: equalsIgnoringWhitespace("""
+          Because pub global activate depends on foo >1.1.0 which doesn't match
+            any versions, version solving failed.
+        """),
         exitCode: exit_codes.DATA);
   });
 }

test/hosted/fail_gracefully_on_url_resolve_test.dart

@@ -2,8 +2,6 @@
 // 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.
 
-@Skip()
-
 import 'package:test/test.dart';
 
 import 'package:pub/src/exit_codes.dart' as exit_codes;

test/hosted/offline_test.dart

@@ -2,8 +2,6 @@
 // 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.
 
-@Skip()
-
 import 'package:test/test.dart';
 
 import 'package:pub/src/exit_codes.dart' as exit_codes;
@@ -65,9 +63,10 @@ main() {
       await pubCommand(command,
           args: ['--offline'],
           exitCode: exit_codes.UNAVAILABLE,
-          error: "Could not find package foo in cache.\n"
-              "Depended on by:\n"
-              "- myapp");
+          error: equalsIgnoringWhitespace("""
+            Because myapp depends on foo any which doesn't exist (could not find
+              package foo in cache), version solving failed.
+          """));
     });
 
     test('fails gracefully if no cached versions match', () async {
@@ -81,9 +80,10 @@ main() {
       await d.appDir({"foo": ">2.0.0"}).create();
 
       await pubCommand(command,
-          args: ['--offline'],
-          error: "Package foo has no versions that match >2.0.0 derived from:\n"
-              "- myapp depends on version >2.0.0");
+          args: ['--offline'], error: equalsIgnoringWhitespace("""
+            Because myapp depends on foo >2.0.0 which doesn't match any
+              versions, version solving failed.
+          """));
     });
 
     test(
@@ -99,9 +99,10 @@ main() {
       await pubCommand(command,
           args: ['--offline'],
           exitCode: exit_codes.UNAVAILABLE,
-          error: "Could not find package foo in cache.\n"
-              "Depended on by:\n"
-              "- myapp");
+          error: equalsIgnoringWhitespace("""
+            Because myapp depends on foo any which doesn't exist (could not find
+              package foo in cache), version solving failed.
+          """));
     });
 
     test('downgrades to the version in the cache if necessary', () async {

test/sdk_test.dart

@@ -84,7 +84,7 @@ main() {
           .file("$appPath/pubspec.lock",
               allOf([isNot(contains("0.0.1")), contains("0.0.2")]))
           .validate();
-    }, skip: true);
+    });
 
     group("fails if", () {
       test("the version constraint doesn't match", () async {
@@ -93,33 +93,33 @@ main() {
         }).create();
         await pubCommand(command,
             environment: {'FLUTTER_ROOT': p.join(d.sandbox, 'flutter')},
-            error: 'Package foo has no versions that match >=1.0.0 <2.0.0 '
-                'derived from:\n'
-                '- myapp depends on version ^1.0.0');
+            error: equalsIgnoringWhitespace("""
+              Because myapp depends on foo ^1.0.0 from sdk which doesn't match
+                any versions, version solving failed.
+            """));
       });
 
       test("the SDK is unknown", () async {
         await d.appDir({
           "foo": {"sdk": "unknown"}
         }).create();
-        await pubCommand(command,
-            error: 'Unknown SDK "unknown".\n'
-                'Depended on by:\n'
-                '- myapp',
-            exitCode: exit_codes.UNAVAILABLE);
+        await pubCommand(command, error: equalsIgnoringWhitespace("""
+              Because myapp depends on foo any from sdk which doesn't exist
+                (unknown SDK "unknown"), version solving failed.
+            """), exitCode: exit_codes.UNAVAILABLE);
       });
 
       test("the SDK is unavailable", () async {
         await d.appDir({
           "foo": {"sdk": "flutter"}
         }).create();
-        await pubCommand(command,
-            error: 'The Flutter SDK is not available.\n'
-                'Flutter users should run `flutter packages get` instead of '
-                '`pub get`.\n'
-                'Depended on by:\n'
-                '- myapp',
-            exitCode: exit_codes.UNAVAILABLE);
+        await pubCommand(command, error: equalsIgnoringWhitespace("""
+              Because myapp depends on foo any from sdk which doesn't exist (the
+                Flutter SDK is not available), version solving failed.
+
+              Flutter users should run `flutter packages get` instead of `pub
+                get`.
+            """), exitCode: exit_codes.UNAVAILABLE);
       });
 
       test("the SDK doesn't contain the package", () async {
@@ -128,22 +128,24 @@ main() {
         }).create();
         await pubCommand(command,
             environment: {'FLUTTER_ROOT': p.join(d.sandbox, 'flutter')},
-            error: 'Could not find package bar in the Flutter SDK.\n'
-                'Depended on by:\n'
-                '- myapp',
+            error: equalsIgnoringWhitespace("""
+              Because myapp depends on bar any from sdk which doesn't exist
+                (could not find package bar in the Flutter SDK), version solving
+                failed.
+            """),
             exitCode: exit_codes.UNAVAILABLE);
       });
 
       test("the Dart SDK doesn't contain the package", () async {
         await d.appDir({
           "bar": {"sdk": "dart"}
         }).create();
-        await pubCommand(command,
-            error: 'Could not find package bar in the Dart SDK.\n'
-                'Depended on by:\n'
-                '- myapp',
-            exitCode: exit_codes.UNAVAILABLE);
+        await pubCommand(command, error: equalsIgnoringWhitespace("""
+              Because myapp depends on bar any from sdk which doesn't exist
+                (could not find package bar in the Dart SDK), version solving
+                failed.
+            """), exitCode: exit_codes.UNAVAILABLE);
       });
-    }, skip: true);
+    });
   });
 }

test/unknown_source_test.dart

@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE d.file.
 
-@Skip()
-
 import 'dart:convert';
 
 import 'package:test/test.dart';
@@ -18,8 +16,10 @@ main() {
         "foo": {"bad": "foo"}
       }).create();
 
-      await pubCommand(command,
-          error: 'Package myapp depends on foo from unknown source "bad".');
+      await pubCommand(command, error: equalsIgnoringWhitespace("""
+        Because myapp depends on foo from unknown source "bad", version solving
+          failed.
+      """));
     });
 
     test(
@@ -36,8 +36,11 @@ main() {
         "foo": {"path": "../foo"}
       }).create();
 
-      await pubCommand(command,
-          error: 'Package foo depends on bar from unknown source "bad".');
+      await pubCommand(command, error: equalsIgnoringWhitespace("""
+        Because every version of foo from path depends on bar from unknown
+          source "bad", foo from path is forbidden.
+        So, because myapp depends on foo from path, version solving failed.
+      """));
     });
 
     test('ignores unknown source in lockfile', () async {