Fix null error. (#4056)

* Fix null error.

* Add second test case.

Author: davidmorgan

build/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.5.3-wip
+
+- Use `build_runner_core` 9.1.1.
+
 ## 2.5.2
 
 - Use `build_runner_core` 9.1.0.

build/pubspec.yaml

@@ -1,5 +1,5 @@
 name: build
-version: 2.5.2
+version: 2.5.3-wip
 description: A package for authoring build_runner compatible code generators.
 repository: https://github.com/dart-lang/build/tree/master/build
 resolution: workspace
@@ -10,7 +10,7 @@ environment:
 dependencies:
   analyzer: '>=6.9.0 <8.0.0'
   async: ^2.5.0
-  build_runner_core: '9.1.0'
+  build_runner_core: '9.1.1-wip'
   built_collection: ^5.1.1
   built_value: ^8.9.5
   convert: ^3.0.0
@@ -24,7 +24,7 @@ dependencies:
   pool: ^1.5.0
 
 dev_dependencies:
-  build_resolvers: '2.5.2'
+  build_resolvers: '2.5.3-wip'
   build_test: ^3.1.0
   built_value_generator: ^8.9.5
   dart_flutter_team_lints: ^3.1.0

build_resolvers/CHANGELOG.md

@@ -1,10 +1,14 @@
+## 2.5.3-wip
+
+- Use `build_runner_core` 9.1.1.
+
 ## 2.5.2
 
 - Simplify warnings for outdated `analyzer`.
 
 ## 2.5.1
 
-- Use `build_runner_core` 2.5.1.
+- Use `build_runner_core` 9.0.1.
 
 ## 2.5.0
 

build_resolvers/pubspec.yaml

@@ -1,5 +1,5 @@
 name: build_resolvers
-version: 2.5.2
+version: 2.5.3-wip
 description: Resolve Dart code in a Builder
 repository: https://github.com/dart-lang/build/tree/master/build_resolvers
 resolution: workspace
@@ -10,8 +10,8 @@ environment:
 dependencies:
   analyzer: '>=6.9.0 <8.0.0'
   async: ^2.5.0
-  build: '2.5.2'
-  build_runner_core: '9.1.0'
+  build: '2.5.3-wip'
+  build_runner_core: '9.1.1-wip'
   collection: ^1.17.0
   convert: ^3.1.1
   crypto: ^3.0.0

build_runner/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 2.5.3-wip
+
+- Bug fix: fix corner case with checked in generated output that could cause
+  a crash.
+
 ## 2.5.2
 
 - Simplify warnings for outdated `analyzer`.

build_runner/pubspec.yaml

@@ -1,5 +1,5 @@
 name: build_runner
-version: 2.5.2
+version: 2.5.3-wip
 description: A build system for Dart code generation and modular compilation.
 repository: https://github.com/dart-lang/build/tree/master/build_runner
 resolution: workspace
@@ -16,11 +16,11 @@ dependencies:
   analyzer: '>=4.4.0 <8.0.0'
   args: ^2.0.0
   async: ^2.5.0
-  build: '2.5.2'
+  build: '2.5.3-wip'
   build_config: ">=1.1.0 <1.2.0"
   build_daemon: ^4.0.0
-  build_resolvers: '2.5.2'
-  build_runner_core: '9.1.0'
+  build_resolvers: '2.5.3-wip'
+  build_runner_core: '9.1.1-wip'
   code_builder: ^4.2.0
   collection: ^1.15.0
   crypto: ^3.0.0

build_runner_core/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 9.1.1-wip
+
+- Bug fix: fix corner case with checked in generated output that could cause
+  a crash.
+
 ## 9.1.0
 
 - More detailed tracking of reads for the benefit of `build_test`.

build_runner_core/lib/src/asset_graph/graph.dart

@@ -124,7 +124,7 @@ class AssetGraph implements GeneratedAssetHider {
     );
     // Pre-emptively compute digests for the nodes we know have outputs.
     await graph._setDigests(
-      sources.where((id) => graph.get(id)!.primaryOutputs.isNotEmpty),
+      sources.where((id) => graph.get(id)?.primaryOutputs.isNotEmpty == true),
       digestReader,
     );
     // Always compute digests for all internal nodes.
@@ -481,6 +481,8 @@ class AssetGraph implements GeneratedAssetHider {
   ///
   /// If [placeholders] is supplied they will be added to [newSources] to create
   /// the full input set.
+  ///
+  /// May remove nodes if sources overlap with generated outputs.
   void _addOutputsForSources(
     BuildPhases buildPhases,
     Set<AssetId> newSources,

build_runner_core/pubspec.yaml

@@ -1,5 +1,5 @@
 name: build_runner_core
-version: 9.1.0
+version: 9.1.1-wip
 description: Core tools to organize the structure of a build and run Builders.
 repository: https://github.com/dart-lang/build/tree/master/build_runner_core
 resolution: workspace
@@ -15,10 +15,10 @@ platforms:
 dependencies:
   analyzer: '>=6.9.0 <8.0.0'
   async: ^2.5.0
-  build: '2.5.2'
+  build: '2.5.3-wip'
   build_config: ^1.0.0
-  build_resolvers: '2.5.2'
-  build_runner: '2.5.2'
+  build_resolvers: '2.5.3-wip'
+  build_runner: '2.5.3-wip'
   built_collection: ^5.1.1
   built_value: ^8.10.1
   collection: ^1.15.0

build_runner_core/test/invalidation/checked_in_output_test.dart

@@ -11,20 +11,20 @@ void main() {
 
   setUp(() {
     tester = InvalidationTester();
-
-    // Start with output source on disk.
-    //
-    // The ordering of sources matters because a different codepath in
-    // `graph.dart` is triggered depending on whether a source is first
-    // processed as an input or as a generated output of another input.
-    //
-    // So for `a` have the output come first, and for `b` the input come
-    // first.
-    tester.sources(['a.g', 'a', 'b', 'b.g']);
   });
 
   group('a <== a.g, a <== a.other', () {
     setUp(() {
+      // Start with output source on disk.
+      //
+      // The ordering of sources matters because a different codepath in
+      // `graph.dart` is triggered depending on whether a source is first
+      // processed as an input or as a generated output of another input.
+      //
+      // So for `a` have the output come first, and for `b` the input come
+      // first.
+      tester.sources(['a.g', 'a', 'b', 'b.g']);
+
       tester.builder(from: '', to: '.g', outputIsVisible: true)
         ..reads('')
         ..writes('.g');
@@ -37,7 +37,7 @@ void main() {
     test('checked in outputs are not treated as inputs', () async {
       expect(
         await tester.build(),
-        // If outputs were treated by inputs there would be outputs created like
+        // If outputs were treated as inputs there would be outputs created like
         // `a.g.g.other`.
         Result(
           written: [
@@ -52,4 +52,46 @@ void main() {
       );
     });
   });
+
+  group('a <== a.g', () {
+    setUp(() {
+      // Start with output source on disk that the build would not actually
+      // write: with the output of a previous build used as input.
+      //
+      // The order matters because it affects the codepath in `graph.dart`.
+      tester.sources(['a.g.g', 'a.g', 'a']);
+
+      tester.builder(from: '', to: '.g', outputIsVisible: true)
+        ..reads('')
+        ..writes('.g');
+    });
+
+    test('can ignore multiple level pregenerated output', () async {
+      expect(await tester.build(), Result(written: ['a.g']));
+    });
+  });
+
+  group('a <== a.g <== a.g.other', () {
+    setUp(() {
+      // Start with output source on disk that the build would not actually
+      // write: with the output of a previous build used as input.
+      //
+      // The order matters because it affects the codepath in `graph.dart`.
+      tester.sources(['a.g.other.g', 'a.g.other', 'a.g', 'a']);
+
+      tester.builder(from: '', to: '.g', outputIsVisible: true)
+        ..reads('')
+        ..writes('.g');
+      tester.builder(from: '.g', to: '.g.other', outputIsVisible: true)
+        ..reads('.g')
+        ..writes('.g.other');
+    });
+
+    test(
+      'can ignore multiple level pregenerated output from two builders',
+      () async {
+        expect(await tester.build(), Result(written: ['a.g', 'a.g.other']));
+      },
+    );
+  });
 }