Root: Rather than use @AutoCodec, use a handwritten ObjectCodec that allows us to optimize for the common case of a very popular Root.
Our serialization scheme is: We are magically given a likely-to-be-popular Root instance `p` and then whenever we would serialize a Root `r`, we canonicalize `r` to `p` if they are `r.equals(p)`.
The Root#fromPath and Root#absoluteRoot methods permit creation of Root instances that are equivalent, and these methods are unfortunately very widely used in the codebase. Therefore, a serialization scheme that tries to make use of Object identity is brittle in the face of future changes.
While I'm here, delete Root#getFingerprint. An earlier commit (https://github.com/bazelbuild/bazel/commit/ce6ad29c88084fb327856149a39e2771e544cfa5) made this dead code.
RELNOTES: None
PiperOrigin-RevId: 300826154
diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/ArtifactFunctionTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/ArtifactFunctionTest.java
index b96d5c1..597f7a9 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/ArtifactFunctionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/ArtifactFunctionTest.java
@@ -289,6 +289,9 @@
true);
new SerializationTester(actionExecutionValue)
.addDependency(FileSystem.class, root.getFileSystem())
+ .addDependency(
+ Root.RootCodecDependencies.class,
+ new Root.RootCodecDependencies(Root.absoluteRoot(root.getFileSystem())))
.runTests();
}
