Expose a new java_library rule factory with sharded java compilation …

…support

I think exporting a factory method makes more sense, to allow consumers to export the rule with whatever name they like, and set a default value for the shard size. Tucking it under the experimental export also lets us get the flag-guarding for free.

PiperOrigin-RevId: 565396979
Change-Id: I758d07a6eb9c95c6d44c5698f725b4a4a1e5185f

src/main/starlark/builtins_bzl/bazel/exports.bzl

@@ -14,16 +14,16 @@
 
 """Exported builtins symbols that are specific to OSS Bazel."""
 
-load("@_builtins//:common/java/java_library.bzl", "JAVA_LIBRARY_ATTRS", "bazel_java_library_rule", "java_library")
-load("@_builtins//:common/java/java_plugin.bzl", "java_plugin")
+load("@_builtins//:common/cc/cc_proto_library.bzl", "cc_proto_aspect", "cc_proto_library")
 load("@_builtins//:common/java/java_import.bzl", "java_import")
+load("@_builtins//:common/java/java_library.bzl", "JAVA_LIBRARY_ATTRS", "bazel_java_library_rule", "java_library", "make_sharded_java_library")
+load("@_builtins//:common/java/java_plugin.bzl", "java_plugin")
 load("@_builtins//:common/java/proto/java_proto_library.bzl", "java_proto_library")
-load("@_builtins//:common/cc/cc_proto_library.bzl", "cc_proto_aspect", "cc_proto_library")
-load(":bazel/java/bazel_java_binary_wrapper.bzl", "java_binary", "java_test")
 load("@_builtins//:common/python/py_binary_macro.bzl", "py_binary")
+load("@_builtins//:common/python/py_internal.bzl", "py_internal")
 load("@_builtins//:common/python/py_library_macro.bzl", "py_library")
 load("@_builtins//:common/python/py_test_macro.bzl", "py_test")
-load("@_builtins//:common/python/py_internal.bzl", "py_internal")
+load(":bazel/java/bazel_java_binary_wrapper.bzl", "java_binary", "java_test")
 
 exported_toplevels = {
     # This is an experimental export in Bazel. The interface will change in a way
@@ -32,6 +32,7 @@ exported_toplevels = {
     "experimental_java_library_export_do_not_use": struct(
         bazel_java_library_rule = bazel_java_library_rule,
         JAVA_LIBRARY_ATTRS = JAVA_LIBRARY_ATTRS,
+        sharded_java_library = make_sharded_java_library,
     ),
     "cc_proto_aspect": cc_proto_aspect,
     "py_internal": py_internal,

src/main/starlark/builtins_bzl/common/java/java_library.bzl

@@ -16,11 +16,11 @@
 Definition of java_library rule.
 """
 
-load(":common/java/basic_java_library.bzl", "BASIC_JAVA_LIBRARY_IMPLICIT_ATTRS", "basic_java_library", "construct_defaultinfo")
-load(":common/rule_util.bzl", "merge_attrs")
-load(":common/java/java_semantics.bzl", "semantics")
 load(":common/cc/cc_info.bzl", "CcInfo")
+load(":common/java/basic_java_library.bzl", "BASIC_JAVA_LIBRARY_IMPLICIT_ATTRS", "basic_java_library", "construct_defaultinfo")
 load(":common/java/java_info.bzl", "JavaInfo", "JavaPluginInfo")
+load(":common/java/java_semantics.bzl", "semantics")
+load(":common/rule_util.bzl", "merge_attrs")
 
 def bazel_java_library_rule(
         ctx,
@@ -166,17 +166,27 @@ JAVA_LIBRARY_ATTRS = merge_attrs(
     },
 )
 
-java_library = rule(
-    _proxy,
-    attrs = merge_attrs(
-        JAVA_LIBRARY_ATTRS,
-        {"_use_auto_exec_groups": attr.bool(default = True)},
-    ),
-    provides = [JavaInfo],
-    outputs = {
-        "classjar": "lib%{name}.jar",
-        "sourcejar": "lib%{name}-src.jar",
-    },
-    fragments = ["java", "cpp"],
-    toolchains = [semantics.JAVA_TOOLCHAIN],
-)
+def _make_java_library_rule(extra_attrs = {}):
+    return rule(
+        _proxy,
+        attrs = merge_attrs(
+            JAVA_LIBRARY_ATTRS,
+            {"_use_auto_exec_groups": attr.bool(default = True)},
+            extra_attrs,
+        ),
+        provides = [JavaInfo],
+        outputs = {
+            "classjar": "lib%{name}.jar",
+            "sourcejar": "lib%{name}-src.jar",
+        },
+        fragments = ["java", "cpp"],
+        toolchains = [semantics.JAVA_TOOLCHAIN],
+    )
+
+java_library = _make_java_library_rule()
+
+# for experimental_java_library_export_do_not_use
+def make_sharded_java_library(default_shard_size):
+    return _make_java_library_rule({
+        "experimental_javac_shard_size": attr.int(default = default_shard_size),
+    })

src/test/java/com/google/devtools/build/lib/bazel/rules/java/BUILD

@@ -17,10 +17,12 @@ java_library(
     name = "JavaTests_lib",
     srcs = glob(["*.java"]),
     deps = [
+        "//src/main/java/com/google/devtools/build/lib/actions",
         "//src/main/java/com/google/devtools/build/lib/analysis:actions/template_expansion_action",
         "//src/main/java/com/google/devtools/build/lib/analysis:configured_target",
         "//src/main/java/com/google/devtools/build/lib/bazel/rules/java:bazel_java_semantics",
         "//src/main/java/com/google/devtools/build/lib/packages",
+        "//src/main/java/com/google/devtools/build/lib/rules/java:java-compilation",
         "//src/main/java/com/google/devtools/build/lib/util:os",
         "//src/main/java/com/google/devtools/build/lib/vfs:pathfragment",
         "//src/test/java/com/google/devtools/build/lib/analysis/util",

src/test/java/com/google/devtools/build/lib/bazel/rules/java/JavaConfiguredTargetsTest.java

@@ -20,9 +20,12 @@
 import static com.google.devtools.build.lib.testutil.TestConstants.TOOLS_REPOSITORY;
 
 import com.google.common.base.Joiner;
+import com.google.common.collect.ImmutableList;
+import com.google.devtools.build.lib.actions.Action;
 import com.google.devtools.build.lib.analysis.ConfiguredTarget;
 import com.google.devtools.build.lib.analysis.actions.TemplateExpansionAction;
 import com.google.devtools.build.lib.analysis.util.BuildViewTestCase;
+import com.google.devtools.build.lib.rules.java.JavaCompileAction;
 import com.google.devtools.build.lib.util.OS;
 import java.util.Arrays;
 import java.util.Objects;
@@ -93,4 +96,37 @@ public void javaTestSetsSecurityManagerPropertyOnVersion17() throws Exception {
       assertThat(jvmFlags).contains("-Djava.security.manager=allow");
     }
   }
+
+  @Test
+  public void experimentalShardedJavaLibrary_succeeds() throws Exception {
+    setBuildLanguageOptions("--experimental_java_library_export");
+    scratch.file(
+        "foo/rule.bzl",
+        //
+        "java_library = experimental_java_library_export_do_not_use.sharded_java_library(",
+        "  default_shard_size = 10",
+        ")");
+    scratch.file(
+        "foo/BUILD",
+        "load(':rule.bzl', 'java_library')",
+        "",
+        "java_library(",
+        "  name = 'lib1',",
+        "  srcs = ['1.java', '2.java', '3.java'],",
+        "  experimental_javac_shard_size = 1,",
+        ")",
+        "java_library(",
+        "  name = 'lib2',",
+        "  srcs = ['1.java', '2.java', '3.java'],",
+        "  experimental_javac_shard_size = 2,",
+        ")");
+
+    ImmutableList<Action> compileActionsWithShardSize1 =
+        getActions("//foo:lib1", JavaCompileAction.class);
+    ImmutableList<Action> compileActionsWithShardSize2 =
+        getActions("//foo:lib2", JavaCompileAction.class);
+
+    assertThat(compileActionsWithShardSize1).hasSize(3);
+    assertThat(compileActionsWithShardSize2).hasSize(2);
+  }
 }