test case for https://github.com/bazelbuild/bazel/issues/10019

bazel.diff

diff --git a/src/test/java/com/google/devtools/build/lib/rules/java/JavaSkylarkApiTest.java b/src/test/java/com/google/devtools/build/lib/rules/java/JavaSkylarkApiTest.java
index 025812d..0e7b2a3 100644
--- a/src/test/java/com/google/devtools/build/lib/rules/java/JavaSkylarkApiTest.java
+++ b/src/test/java/com/google/devtools/build/lib/rules/java/JavaSkylarkApiTest.java
@@ -130,6 +130,73 @@ public class JavaSkylarkApiTest extends BuildViewTestCase {
   }
 
   @Test
+  public void testJavaRuntimeProviderJavaLauncher() throws Exception {
+    scratch.file(
+        "a/BUILD",
+        "load(':rule.bzl', 'jrule')",
+        "load('"
+            + TestConstants.TOOLS_REPOSITORY
+            + "//tools/jdk:java_toolchain_alias.bzl', 'java_runtime_alias')",
+        "java_runtime(name='jvm', srcs=[], java_home='/foo/bar')",
+        "java_runtime_alias(name='alias')",
+        "jrule(name='r')",
+        "constraint_value(",
+        "    name = 'constraint',",
+        "    constraint_setting = '"
+            + TestConstants.PLATFORM_PACKAGE_ROOT
+            + "/java/constraints:runtime',",
+        ")",
+        "toolchain(",
+        "    name = 'java_runtime_toolchain',",
+        "    toolchain = ':jvm',",
+        "    toolchain_type = '"
+            + TestConstants.TOOLS_REPOSITORY
+            + "//tools/jdk:runtime_toolchain_type',",
+        "    target_compatible_with = [':constraint'],",
+        ")",
+        "platform(",
+        "    name = 'platform',",
+        "    constraint_values = [':constraint'],",
+        ")",
+        "cc_binary(",
+        "    name = 'launcher',",
+        ")");
+
+    scratch.file(
+        "a/rule.bzl",
+        "load('//myinfo:myinfo.bzl', 'MyInfo')",
+        "def _impl(ctx):",
+        "  provider = ctx.attr._java_runtime[java_common.JavaRuntimeInfo]",
+        "  return MyInfo(",
+        "    java_home_exec_path = provider.java_home,",
+        "    java_executable_exec_path = provider.java_executable_exec_path,",
+        "    java_home_runfiles_path = provider.java_home_runfiles_path,",
+        "    java_executable_runfiles_path = provider.java_executable_runfiles_path,",
+        "  )",
+        "jrule = rule(_impl, attrs = { '_java_runtime': attr.label(default=Label('//a:alias'))})");
+
+    useConfiguration(
+        "--javabase=//a:jvm", "--extra_toolchains=//a:all", "--platforms=//a:platform", "--java_launcher=//a:launcher");
+    ConfiguredTarget ct = getConfiguredTarget("//a:r");
+    StructImpl myInfo = getMyInfoFromTarget(ct);
+    @SuppressWarnings("unchecked")
+    PathFragment javaHomeExecPath = (PathFragment) myInfo.getValue("java_home_exec_path");
+    assertThat(javaHomeExecPath.getPathString()).isEqualTo("/foo/bar");
+    @SuppressWarnings("unchecked")
+    PathFragment javaExecutableExecPath =
+        (PathFragment) myInfo.getValue("java_executable_exec_path");
+    assertThat(javaExecutableExecPath.getPathString()).startsWith("/foo/bar/bin/java");
+    @SuppressWarnings("unchecked")
+    PathFragment javaHomeRunfilesPath = (PathFragment) myInfo.getValue("java_home_runfiles_path");
+    // TODO should this be derived from --java_launcher?
+    assertThat(javaHomeRunfilesPath.getPathString()).isEqualTo("/foo/bar");
+    @SuppressWarnings("unchecked")
+    PathFragment javaExecutableRunfiles =
+        (PathFragment) myInfo.getValue("java_executable_runfiles_path");
+    assertThat(javaExecutableRunfiles.getPathString()).startsWith("/a/launcher");
+  }
+
+  @Test
   public void testJavaRuntimeProviderJavaHermetic() throws Exception {
     scratch.file(
         "a/BUILD",