Add NodeType to AssetNode. (#3905)

build_runner/test/generate/watch_test.dart

@@ -364,7 +364,7 @@ void main() {
         var builderOptionsId = makeAssetId('a|Phase0.builderOptions');
         var builderOptionsNode = BuilderOptionsAssetNode(
           builderOptionsId,
-          computeBuilderOptionsDigest(defaultBuilderOptions),
+          lastKnownDigest: computeBuilderOptionsDigest(defaultBuilderOptions),
         );
         expectedGraph.add(builderOptionsNode);
 

build_runner_core/lib/src/asset_graph/graph.dart

@@ -112,7 +112,7 @@ class AssetGraph {
   void _add(AssetNode node) {
     var existing = get(node.id);
     if (existing != null) {
-      if (existing is SyntheticSourceAssetNode) {
+      if (existing.type == NodeType.syntheticSource) {
         // Don't call _removeRecursive, that recursively removes all transitive
         // primary outputs. We only want to remove this node.
         _nodesByPackage[existing.id.package]!.remove(existing.id.path);
@@ -164,7 +164,7 @@ class AssetGraph {
         add(
           BuilderOptionsAssetNode(
             builderOptionsIdForAction(phase, phaseNum),
-            computeBuilderOptionsDigest(phase.builderOptions),
+            lastKnownDigest: computeBuilderOptionsDigest(phase.builderOptions),
           ),
         );
       } else if (phase is PostBuildPhase) {
@@ -173,7 +173,9 @@ class AssetGraph {
           add(
             BuilderOptionsAssetNode(
               builderOptionsIdForAction(builderAction, actionNum),
-              computeBuilderOptionsDigest(builderAction.builderOptions),
+              lastKnownDigest: computeBuilderOptionsDigest(
+                builderAction.builderOptions,
+              ),
             ),
           );
           actionNum++;
@@ -238,7 +240,7 @@ class AssetGraph {
       }
     }
     // Synthetic nodes need to be kept to retain dependency tracking.
-    if (node is! SyntheticSourceAssetNode) {
+    if (node.type != NodeType.syntheticSource) {
       _nodesByPackage[id.package]!.remove(id.path);
     }
     return removedIds;
@@ -274,7 +276,7 @@ class AssetGraph {
 
   /// All the source files in the graph.
   Iterable<AssetId> get sources =>
-      allNodes.whereType<SourceAssetNode>().map((n) => n.id);
+      allNodes.where((n) => n.type == NodeType.source).map((n) => n.id);
 
   /// Updates graph structure, invalidating and deleting any outputs that were
   /// affected.
@@ -332,9 +334,12 @@ class AssetGraph {
       }
     }
 
-    removeIds
-        .where((id) => get(id) is SourceAssetNode)
-        .forEach(addTransitivePrimaryOutputs);
+    for (final id in removeIds) {
+      final node = get(id);
+      if (node != null && node.type == NodeType.source) {
+        addTransitivePrimaryOutputs(id);
+      }
+    }
 
     // The generated nodes to actually delete from the file system.
     var idsToDelete = Set<AssetId>.from(transitiveRemovedIds)
@@ -397,9 +402,12 @@ class AssetGraph {
 
     // Remove all deleted source assets from the graph, which also recursively
     // removes all their primary outputs.
-    for (var id in removeIds.where((id) => get(id) is SourceAssetNode)) {
-      invalidateNodeAndDeps(id);
-      _removeRecursive(id);
+    for (final id in removeIds) {
+      final node = get(id);
+      if (node != null && node.type == NodeType.source) {
+        invalidateNodeAndDeps(id);
+        _removeRecursive(id);
+      }
     }
 
     return invalidatedIds;
@@ -480,7 +488,7 @@ class AssetGraph {
   ) {
     var phaseOutputs = <AssetId>{};
     var buildOptionsNodeId = builderOptionsIdForAction(phase, phaseNum);
-    var builderOptionsNode = get(buildOptionsNodeId) as BuilderOptionsAssetNode;
+    var builderOptionsNode = get(buildOptionsNodeId)!;
     var inputs =
         allInputs.where((input) => _actionMatches(phase, input)).toList();
     for (var input in inputs) {
@@ -541,12 +549,15 @@ class AssetGraph {
   Set<AssetId> _addGeneratedOutputs(
     Iterable<AssetId> outputs,
     int phaseNumber,
-    BuilderOptionsAssetNode builderOptionsNode,
+    AssetNode builderOptionsNode,
     List<BuildPhase> buildPhases,
     String rootPackage, {
     required AssetId primaryInput,
     required bool isHidden,
   }) {
+    if (builderOptionsNode.type != NodeType.builderOptions) {
+      throw ArgumentError('Expected node of type NodeType.builderOptionsNode');
+    }
     var removed = <AssetId>{};
     for (var output in outputs) {
       AssetNode? existing;

build_runner_core/lib/src/asset_graph/node.dart

@@ -11,10 +11,24 @@ import 'package:glob/glob.dart';
 
 import '../generate/phase.dart';
 
+/// Types of [AssetNode].
+enum NodeType {
+  builderOptions,
+  generated,
+  glob,
+  internal,
+  placeholder,
+  postProcessAnchor,
+  source,
+  syntheticSource,
+}
+
 /// A node in the asset graph which may be an input to other assets.
 abstract class AssetNode {
   final AssetId id;
 
+  final NodeType type;
+
   /// The assets that any [Builder] in the build graph declares it may output
   /// when run on this asset.
   final Set<AssetId> primaryOutputs = <AssetId>{};
@@ -68,15 +82,7 @@ abstract class AssetNode {
   /// and re-added, in which case it won't have a digest.
   bool get isInteresting => outputs.isNotEmpty || lastKnownDigest != null;
 
-  AssetNode(this.id, {this.lastKnownDigest});
-
-  /// Work around issue where you can't mixin classes into a class with optional
-  /// constructor args.
-  AssetNode._forMixins(this.id);
-
-  /// Work around issue where you can't mixin classes into a class with optional
-  /// constructor args, this one includes the digest.
-  AssetNode._forMixinsWithDigest(this.id, this.lastKnownDigest);
+  AssetNode(this.id, {required this.type, this.lastKnownDigest});
 
   @override
   String toString() => 'AssetNode: $id';
@@ -94,15 +100,17 @@ class InternalAssetNode extends AssetNode {
   @override
   bool get isValidInput => false;
 
-  InternalAssetNode(super.id, {super.lastKnownDigest});
+  InternalAssetNode(super.id, {super.lastKnownDigest})
+    : super(type: NodeType.internal);
 
   @override
   String toString() => 'InternalAssetNode: $id';
 }
 
 /// A node which is an original source asset (not generated).
 class SourceAssetNode extends AssetNode {
-  SourceAssetNode(super.id, {super.lastKnownDigest});
+  SourceAssetNode(super.id, {super.lastKnownDigest})
+    : super(type: NodeType.source);
 
   @override
   String toString() => 'SourceAssetNode: $id';
@@ -172,65 +180,68 @@ class GeneratedAssetNode extends AssetNode implements NodeWithInputs {
     required this.isFailure,
     required this.primaryInput,
     required this.builderOptionsId,
-  }) : inputs = inputs != null ? HashSet.from(inputs) : HashSet();
+  }) : inputs = inputs != null ? HashSet.from(inputs) : HashSet(),
+       super(type: NodeType.generated);
 
   @override
   String toString() =>
       'GeneratedAssetNode: $id generated from input $primaryInput.';
 }
 
-/// A node which is not a generated or source asset.
+/// A non-existent source.
 ///
-/// These are typically not readable or valid as inputs.
-mixin _SyntheticAssetNode implements AssetNode {
+/// Typically these are created as a result of `canRead` calls for assets that
+/// don't exist in the graph. We still need to set up proper dependencies so
+/// that if that asset gets added later the outputs are properly invalidated.
+class SyntheticSourceAssetNode extends AssetNode {
   @override
   bool get isReadable => false;
 
   @override
   bool get isValidInput => false;
-}
 
-/// A [_SyntheticAssetNode] representing a non-existent source.
-///
-/// Typically these are created as a result of `canRead` calls for assets that
-/// don't exist in the graph. We still need to set up proper dependencies so
-/// that if that asset gets added later the outputs are properly invalidated.
-class SyntheticSourceAssetNode extends AssetNode with _SyntheticAssetNode {
-  SyntheticSourceAssetNode(super.id) : super._forMixins();
+  SyntheticSourceAssetNode(super.id) : super(type: NodeType.syntheticSource);
 }
 
-/// A [_SyntheticAssetNode] which represents an individual [BuilderOptions]
-/// object.
+/// An individual [BuilderOptions] object.
 ///
 /// These are used to track the state of a [BuilderOptions] object, and all
 /// [GeneratedAssetNode]s should depend on one of these nodes, which represents
 /// their configuration.
-class BuilderOptionsAssetNode extends AssetNode with _SyntheticAssetNode {
-  BuilderOptionsAssetNode(super.id, Digest super.lastKnownDigest)
-    : super._forMixinsWithDigest();
+class BuilderOptionsAssetNode extends AssetNode {
+  BuilderOptionsAssetNode(super.id, {required super.lastKnownDigest})
+    : super(type: NodeType.builderOptions);
+
+  @override
+  bool get isReadable => false;
+
+  @override
+  bool get isValidInput => false;
 
   @override
   String toString() => 'BuildOptionsAssetNode: $id';
 }
 
 /// Placeholder assets are magic files that are usable as inputs but are not
 /// readable.
-class PlaceHolderAssetNode extends AssetNode with _SyntheticAssetNode {
+class PlaceHolderAssetNode extends AssetNode {
+  @override
+  bool get isReadable => false;
+
   @override
   bool get isValidInput => true;
 
-  PlaceHolderAssetNode(super.id) : super._forMixins();
+  PlaceHolderAssetNode(super.id) : super(type: NodeType.placeholder);
 
   @override
   String toString() => 'PlaceHolderAssetNode: $id';
 }
 
-/// A [_SyntheticAssetNode] which is created for each [primaryInput] to a
-/// [PostBuildAction].
+/// A [primaryInput] to a [PostBuildAction].
 ///
 /// The [outputs] of this node are the individual outputs created for the
 /// [primaryInput] during the [PostBuildAction] at index [actionNumber].
-class PostProcessAnchorNode extends AssetNode with _SyntheticAssetNode {
+class PostProcessAnchorNode extends AssetNode {
   final int actionNumber;
   final AssetId builderOptionsId;
   final AssetId primaryInput;
@@ -242,7 +253,13 @@ class PostProcessAnchorNode extends AssetNode with _SyntheticAssetNode {
     this.actionNumber,
     this.builderOptionsId, {
     this.previousInputsDigest,
-  }) : super._forMixins();
+  }) : super(type: NodeType.postProcessAnchor);
+
+  @override
+  bool get isReadable => false;
+
+  @override
+  bool get isValidInput => false;
 
   PostProcessAnchorNode.forInputAndAction(
     AssetId primaryInput,
@@ -260,7 +277,7 @@ class PostProcessAnchorNode extends AssetNode with _SyntheticAssetNode {
 ///
 /// The [id] must always be unique to a given package, phase, and glob
 /// pattern.
-class GlobAssetNode extends InternalAssetNode implements NodeWithInputs {
+class GlobAssetNode extends AssetNode implements NodeWithInputs {
   final Glob glob;
 
   /// All the potential inputs matching this glob.
@@ -271,6 +288,12 @@ class GlobAssetNode extends InternalAssetNode implements NodeWithInputs {
   @override
   HashSet<AssetId> inputs;
 
+  @override
+  bool get isInteresting => true;
+
+  @override
+  bool get isValidInput => false;
+
   @override
   bool get isReadable => false;
 
@@ -291,7 +314,8 @@ class GlobAssetNode extends InternalAssetNode implements NodeWithInputs {
     HashSet<AssetId>? inputs,
     super.lastKnownDigest,
     this.results,
-  }) : inputs = inputs ?? HashSet();
+  }) : inputs = inputs ?? HashSet(),
+       super(type: NodeType.glob);
 
   static AssetId createId(String package, Glob glob, int phaseNum) => AssetId(
     package,

build_runner_core/lib/src/asset_graph/serialization.dart

@@ -71,7 +71,7 @@ class _AssetGraphDeserializer {
     // current nodes.
     for (var node in graph.allNodes) {
       // These aren't explicitly added as inputs.
-      if (node is BuilderOptionsAssetNode) continue;
+      if (node.type == NodeType.builderOptions) continue;
 
       for (var output in node.outputs) {
         var inputsNode = graph.get(output) as NodeWithInputs?;
@@ -168,7 +168,7 @@ class _AssetGraphDeserializer {
         break;
       case _NodeType.builderOptions:
         assert(serializedNode.length == _WrappedAssetNode._length);
-        node = BuilderOptionsAssetNode(id, digest!);
+        node = BuilderOptionsAssetNode(id, lastKnownDigest: digest!);
         break;
       case _NodeType.placeholder:
         assert(serializedNode.length == _WrappedAssetNode._length);
@@ -346,24 +346,24 @@ class _WrappedAssetNode extends Object with ListMixin implements List {
     var fieldId = _AssetField.values[index];
     switch (fieldId) {
       case _AssetField.nodeType:
-        if (node is SourceAssetNode) {
-          return _NodeType.source.index;
-        } else if (node is GeneratedAssetNode) {
-          return _NodeType.generated.index;
-        } else if (node is GlobAssetNode) {
-          return _NodeType.glob.index;
-        } else if (node is SyntheticSourceAssetNode) {
-          return _NodeType.syntheticSource.index;
-        } else if (node is InternalAssetNode) {
-          return _NodeType.internal.index;
-        } else if (node is BuilderOptionsAssetNode) {
-          return _NodeType.builderOptions.index;
-        } else if (node is PlaceHolderAssetNode) {
-          return _NodeType.placeholder.index;
-        } else if (node is PostProcessAnchorNode) {
-          return _NodeType.postProcessAnchor.index;
-        } else {
-          throw StateError('Unrecognized node type');
+        switch (node.type) {
+          case NodeType.source:
+            return _NodeType.source.index;
+          case NodeType.generated:
+            return _NodeType.generated.index;
+          case NodeType.glob:
+            return _NodeType.glob.index;
+          case NodeType.syntheticSource:
+            return _NodeType.syntheticSource.index;
+          case NodeType.internal:
+            return _NodeType.internal.index;
+          case NodeType.builderOptions:
+            return _NodeType.builderOptions.index;
+
+          case NodeType.placeholder:
+            return _NodeType.placeholder.index;
+          case NodeType.postProcessAnchor:
+            return _NodeType.postProcessAnchor.index;
         }
       case _AssetField.id:
         return serializer.findAssetIndex(node.id, from: node.id, field: 'id');

build_runner_core/lib/src/generate/build_definition.dart

@@ -600,8 +600,13 @@ class _Loader {
       AssetId builderOptionsId,
       BuilderOptions options,
     ) {
-      var builderOptionsNode =
-          assetGraph.get(builderOptionsId) as BuilderOptionsAssetNode;
+      var builderOptionsNode = assetGraph.get(builderOptionsId)!;
+      if (builderOptionsNode.type != NodeType.builderOptions) {
+        throw StateError(
+          'Expected node of type NodeType.builderOptionsNode:'
+          '$builderOptionsNode',
+        );
+      }
       var oldDigest = builderOptionsNode.lastKnownDigest;
       builderOptionsNode.lastKnownDigest = computeBuilderOptionsDigest(options);
       if (builderOptionsNode.lastKnownDigest != oldDigest) {