Replace annotation_processors with plugins

Follow bazel's modules for annotation processors by introducing
a java_plugin module type that can contain extra metadata about
the annotation processor, the processor class and a flag to
specify if the annotation processor is compatible with the
turbine optimization.  Deprecate the annotation_processors
property, which took a list of java_library_host modules, in
favor of the plugins property, which takes a list of java_plugin
modules.  The annotation_processors property will be removed
once all uses have been replaced with plugins.

Bug: 77284273
Test: plugin_test.go
Test: m caliper
Change-Id: I37c1e80eba71ae2d6a06199fb102194a51994989

java/plugin_test.go

@@ -0,0 +1,124 @@
+// Copyright 2019 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package java
+
+import (
+	"android/soong/android"
+	"testing"
+)
+
+func TestNoPlugin(t *testing.T) {
+	ctx := testJava(t, `
+		java_library {
+			name: "foo",
+			srcs: ["a.java"],
+		}
+	`)
+
+	javac := ctx.ModuleForTests("foo", "android_common").Rule("javac")
+	turbine := ctx.ModuleForTests("foo", "android_common").MaybeRule("turbine")
+
+	if turbine.Rule == nil {
+		t.Errorf("expected turbine to be enabled")
+	}
+
+	if javac.Args["processsorpath"] != "" {
+		t.Errorf("want empty processorpath, got %q", javac.Args["processorpath"])
+	}
+
+	// TODO(b/77284273): test for -processor:none if no plugins are enabled
+	if javac.Args["processor"] != "" {
+		t.Errorf("want no -processor argument, got %q", javac.Args["processor"])
+	}
+}
+
+func TestPlugin(t *testing.T) {
+	ctx := testJava(t, `
+		java_library {
+			name: "foo",
+			srcs: ["a.java"],
+			plugins: ["bar"],
+		}
+
+		java_plugin {
+			name: "bar",
+			processor_class: "com.bar",
+			srcs: ["b.java"],
+		}
+	`)
+
+	buildOS := android.BuildOs.String()
+
+	javac := ctx.ModuleForTests("foo", "android_common").Rule("javac")
+	turbine := ctx.ModuleForTests("foo", "android_common").MaybeRule("turbine")
+
+	if turbine.Rule == nil {
+		t.Errorf("expected turbine to be enabled")
+	}
+
+	bar := ctx.ModuleForTests("bar", buildOS+"_common").Rule("javac").Output.String()
+
+	if !inList(bar, javac.Implicits.Strings()) {
+		t.Errorf("foo implicits %v does not contain %q", javac.Implicits.Strings(), bar)
+	}
+
+	if javac.Args["processorpath"] != "-processorpath "+bar {
+		t.Errorf("foo processorpath %q != '-processorpath %s'", javac.Args["processorpath"], bar)
+	}
+
+	if javac.Args["processor"] != "-processor com.bar" {
+		t.Errorf("foo processor %q != '-processor com.bar'", javac.Args["processor"])
+	}
+}
+
+func TestPluginGeneratesApi(t *testing.T) {
+	ctx := testJava(t, `
+		java_library {
+			name: "foo",
+			srcs: ["a.java"],
+			plugins: ["bar"],
+		}
+
+		java_plugin {
+			name: "bar",
+			processor_class: "com.bar",
+			generates_api: true,
+			srcs: ["b.java"],
+		}
+	`)
+
+	buildOS := android.BuildOs.String()
+
+	javac := ctx.ModuleForTests("foo", "android_common").Rule("javac")
+	turbine := ctx.ModuleForTests("foo", "android_common").MaybeRule("turbine")
+
+	if turbine.Rule != nil {
+		t.Errorf("expected turbine to be disabled")
+	}
+
+	bar := ctx.ModuleForTests("bar", buildOS+"_common").Rule("javac").Output.String()
+
+	if !inList(bar, javac.Implicits.Strings()) {
+		t.Errorf("foo implicits %v does not contain %q", javac.Implicits.Strings(), bar)
+	}
+
+	if javac.Args["processorpath"] != "-processorpath "+bar {
+		t.Errorf("foo processorpath %q != '-processorpath %s'", javac.Args["processorpath"], bar)
+	}
+
+	if javac.Args["processor"] != "-processor com.bar" {
+		t.Errorf("foo processor %q != '-processor com.bar'", javac.Args["processor"])
+	}
+}