Add a testcase

test/BUILD

@@ -478,6 +478,26 @@ scala_specs2_junit_test(
     "//test:test_scala_proto_server",
 ]]
 
+# Generate a file containing the rootpaths of a Scala binary.
+genrule(
+   name = "rootpath-script",
+   outs = ["rootpath-script.out"],
+   cmd = """
+       rootpaths=($(rootpaths {}))
+       (IFS='\n'; echo "$${{rootpaths[*]}}") | sort > $@
+   """.format(":ScalaBinary"),
+   srcs = [":ScalaBinary"],
+)
+
+# Validate that the rootpaths point to both the binary
+# and the JAR.
+sh_test(
+  name = "ScalaBinaryRootpaths",
+  srcs = ["rootpaths_binary.sh"],
+  args = ["$(location :rootpath-script.out)"],
+  data = [":rootpath-script.out"],
+)
+
 sh_test(
     name = "test_binary_run_with_large_classpath",
     srcs = ["test_binary_run_with_large_classpath.sh"],

test/rootpaths_binary.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+
+set -eou pipefail
+
+content="$(cat $1)"
+expected=$'test/ScalaBinary\ntest/ScalaBinary.jar'
+if [ "$content" != "$expected" ]; then
+    echo "Unexpected rootpaths: $content"
+    echo "$expected"
+    exit 1
+fi