add test

[ci skip-rust]

[ci skip-build-wheels]

src/python/pants/backend/scala/dependency_inference/symbol_mapper.py

@@ -25,7 +25,7 @@ class FirstPartyScalaTargetsMappingRequest(FirstPartyMappingRequest):
 
 
 @rule(desc="Find all Scala targets in project", level=LogLevel.DEBUG)
-def find_all_java_targets(targets: AllTargets) -> AllScalaTargets:
+def find_all_scala_targets(targets: AllTargets) -> AllScalaTargets:
     return AllScalaTargets(tgt for tgt in targets if tgt.has_field(ScalaSourceField))
 
 

src/python/pants/jvm/dependency_inference/java_scala_interop_test.py

@@ -0,0 +1,103 @@
+# Copyright 2021 Pants project contributors (see CONTRIBUTORS.md).
+# Licensed under the Apache License, Version 2.0 (see LICENSE).
+import textwrap
+
+import pytest
+
+from pants.backend.java.compile.javac import rules as javac_rules
+from pants.backend.java.dependency_inference import symbol_mapper as java_symbol_mapper
+from pants.backend.java.dependency_inference.rules import rules as java_dep_inference_rules
+from pants.backend.java.target_types import JavaSourcesGeneratorTarget, JavaSourceTarget
+from pants.backend.java.target_types import rules as java_target_rules
+from pants.backend.scala import target_types as scala_target_types
+from pants.backend.scala.dependency_inference import rules as scala_dep_inference_rules
+from pants.backend.scala.dependency_inference import scala_parser
+from pants.backend.scala.dependency_inference import symbol_mapper as scala_symbol_mapper
+from pants.backend.scala.target_types import ScalaSourcesGeneratorTarget, ScalaSourceTarget
+from pants.core.util_rules import config_files, source_files
+from pants.core.util_rules.external_tool import rules as external_tool_rules
+from pants.engine.addresses import Address, Addresses
+from pants.engine.rules import QueryRule
+from pants.engine.target import Dependencies, DependenciesRequest
+from pants.jvm.jdk_rules import rules as java_util_rules
+from pants.jvm.resolve.coursier_fetch import rules as coursier_fetch_rules
+from pants.jvm.resolve.coursier_setup import rules as coursier_setup_rules
+from pants.jvm.util_rules import rules as util_rules
+from pants.testutil.rule_runner import PYTHON_BOOTSTRAP_ENV, RuleRunner
+
+NAMED_RESOLVE_OPTIONS = '--jvm-resolves={"test": "coursier_resolve.lockfile"}'
+DEFAULT_RESOLVE_OPTION = "--jvm-default-resolve=test"
+
+
+@pytest.fixture
+def rule_runner() -> RuleRunner:
+    rule_runner = RuleRunner(
+        rules=[
+            *config_files.rules(),
+            *coursier_fetch_rules(),
+            *coursier_setup_rules(),
+            *java_dep_inference_rules(),
+            *external_tool_rules(),
+            *java_target_rules(),
+            *java_util_rules(),
+            *javac_rules(),
+            *java_symbol_mapper.rules(),
+            *source_files.rules(),
+            *scala_parser.rules(),
+            *scala_symbol_mapper.rules(),
+            *scala_dep_inference_rules.rules(),
+            *scala_target_types.rules(),
+            *util_rules(),
+            QueryRule(Addresses, (DependenciesRequest,)),
+        ],
+        target_types=[
+            JavaSourcesGeneratorTarget,
+            JavaSourceTarget,
+            ScalaSourcesGeneratorTarget,
+            ScalaSourceTarget,
+        ],
+    )
+    rule_runner.set_options(
+        args=[NAMED_RESOLVE_OPTIONS, DEFAULT_RESOLVE_OPTION], env_inherit=PYTHON_BOOTSTRAP_ENV
+    )
+    return rule_runner
+
+
+def test_java_infers_scala_dependency(rule_runner: RuleRunner) -> None:
+    rule_runner.write_files(
+        {
+            "org/pantsbuild/lib/BUILD": "scala_sources()\n",
+            "org/pantsbuild/lib/Foo.scala": textwrap.dedent(
+                """
+            package org.pantsbuild.lib
+
+            object Foo {
+              def grok(): Unit = {
+                println("Hello world!")
+              }
+            }
+            """
+            ),
+            "org/pantsbuild/example/BUILD": "java_sources()\n",
+            "org/pantsbuild/example/Bar.java": textwrap.dedent(
+                """
+            package org.pantsbuild.example;
+
+            import org.pantsbuild.lib.Foo$;
+
+            public class Bar {
+              public static void main(String[] args) {
+                Foo$.MODULE$.grok();
+              }
+            }
+            """
+            ),
+        }
+    )
+    example_tgt = rule_runner.get_target(
+        Address("org/pantsbuild/example", target_name="example", relative_file_path="Bar.java")
+    )
+    deps = rule_runner.request(Addresses, [DependenciesRequest(example_tgt[Dependencies])])
+    assert deps == Addresses(
+        [Address("org/pantsbuild/lib", target_name="lib", relative_file_path="Foo.scala")]
+    )