add scala stdlib to java compile classpath, relates to #526

scala/private/rule_impls.bzl

@@ -263,6 +263,8 @@ def try_to_compile_java_jar(ctx, scala_output, all_srcjars, java_srcs,
   providers_of_dependencies = collect_java_providers_of(ctx.attr.deps)
   providers_of_dependencies += collect_java_providers_of(
       implicit_junit_deps_needed_for_java_compilation)
+  providers_of_dependencies += collect_java_providers_of(
+      [ctx.attr._scalalib])
   scala_sources_java_provider = _interim_java_provider_for_java_compilation(
       scala_output)
   providers_of_dependencies += [scala_sources_java_provider]

test/BUILD

@@ -531,6 +531,11 @@ scalapb_proto_library(
     ],
 )
 
+scala_library(
+    name = "java_uses_scala_std_lib",
+    srcs = ["JavaUsesScalaStdLib.java"]
+)
+
 load(":check_statsfile.bzl", "check_statsfile")
 
 check_statsfile("ScalaBinary")

test/JavaUsesScalaStdLib.java

@@ -0,0 +1,9 @@
+package scalarules.test;
+
+public class JavaUsesScalaStdLib {
+
+  public static <A, B> scala.collection.immutable.Map<A, B> scalaMap(java.util.Map<A, B> javaMap) {
+    return null;
+  }
+
+}