Display null safety tag only on migrated packages (#2411)

* Pass correct packages information to AnalysisDriver

* add test

* comments and cleanup

Author: jcollins-g

lib/src/model/package_builder.dart

@@ -21,15 +21,17 @@ import 'package:analyzer/src/generated/source_io.dart';
 import 'package:analyzer/src/source/package_map_resolver.dart';
 import 'package:dartdoc/src/dartdoc_options.dart';
 import 'package:dartdoc/src/logging.dart';
-import 'package:dartdoc/src/model/model.dart';
+import 'package:dartdoc/src/model/model.dart' hide Package;
 import 'package:dartdoc/src/quiver.dart' as quiver;
 import 'package:dartdoc/src/package_config_provider.dart';
 import 'package:dartdoc/src/package_meta.dart'
     show PackageMeta, PackageMetaProvider;
 import 'package:dartdoc/src/render/renderer_factory.dart';
 import 'package:dartdoc/src/special_elements.dart';
 import 'package:meta/meta.dart';
+// TODO(jcollins-g): do not directly import path, use ResourceProvider instead
 import 'package:path/path.dart' as path;
+import 'package:pub_semver/pub_semver.dart';
 
 /// Everything you need to instantiate a PackageGraph object for documenting.
 abstract class PackageBuilder {
@@ -98,6 +100,8 @@ class PubPackageBuilder implements PackageBuilder {
 
   ResourceProvider get resourceProvider => packageMetaProvider.resourceProvider;
 
+  /* late final */ Packages packages;
+
   Future<void> _calculatePackageMap() async {
     assert(_packageMap == null);
     _packageMap = <String, List<Folder>>{};
@@ -106,8 +110,27 @@ class PubPackageBuilder implements PackageBuilder {
         .findPackageConfig(resourceProvider.getFolder(cwd.path));
     if (info == null) return;
 
+    var rpc = resourceProvider.pathContext;
+    // This complicated expression transforms a list of [package_config.Package]
+    // into [analyzer.Packages].  It's a bit confusing because [info.packages]
+    // is actually the list of [package_config.Package] objects, rather than
+    // the [Packages] object we need.
+    packages = Packages(Map.fromEntries(info.packages.map((p) => MapEntry<
+            String, Package>(
+        p.name,
+        Package(
+            name: p.name,
+            rootFolder:
+                resourceProvider.getFolder(rpc.normalize(rpc.fromUri(p.root))),
+            languageVersion: p.languageVersion != null
+                ? Version(p.languageVersion.major, p.languageVersion.minor, 0)
+                : null,
+            libFolder: resourceProvider.getFolder(
+              rpc.normalize(rpc.fromUri(p.packageUriRoot)),
+            ))))));
+
     for (var package in info.packages) {
-      var packagePath = path.normalize(path.fromUri(package.packageUriRoot));
+      var packagePath = rpc.normalize(rpc.fromUri(package.packageUriRoot));
       var resource = resourceProvider.getResource(packagePath);
       if (resource is Folder) {
         _packageMap[package.name] = [resource];
@@ -154,7 +177,6 @@ class PubPackageBuilder implements PackageBuilder {
   }
 
   AnalysisDriver _driver;
-
   AnalysisDriver get driver {
     if (_driver == null) {
       var log = PerformanceLog(null);
@@ -163,13 +185,11 @@ class PubPackageBuilder implements PackageBuilder {
         ..hint = false
         // TODO(jcollins-g): pass in an ExperimentStatus instead?
         ..contextFeatures = FeatureSet.fromEnableFlags(config.enableExperiment);
-
-      // TODO(jcollins-g): Make use of currently not existing API for managing
-      //                   many AnalysisDrivers
+      // TODO(jcollins-g): make use of AnalysisContextCollection()
       // TODO(jcollins-g): make use of DartProject isApi()
       _driver = AnalysisDriver(scheduler, log, resourceProvider,
           MemoryByteStore(), FileContentOverlay(), null, sourceFactory, options,
-          packages: Packages.empty);
+          packages: packages);
       driver.results.listen((_) => logProgress(''));
       driver.exceptions.listen((_) {});
       scheduler.start();

test/end2end/model_test.dart

@@ -491,6 +491,10 @@ void main() {
       expect(exLibrary.name, 'ex');
     });
 
+    test('does not have a null safety label if not null safe', () {
+      expect(exLibrary.isNullSafety, isFalse);
+    });
+
     test('has a line number and column', () {
       expect(exLibrary.characterLocation, isNotNull);
     });