From f90dd822d53ae088d42c8611f495cc0818594a0c Mon Sep 17 00:00:00 2001
From: Omry Yadan <omry@fb.com>
Date: Tue, 26 Jan 2021 14:03:48 -0800
Subject: [PATCH] Fix interpolation in Hydra config node

---
 hydra/core/utils.py |  9 ++++-----
 news/1335.bugfix    |  1 +
 tests/test_hydra.py | 22 ++++++++++++++++++++++
 3 files changed, 27 insertions(+), 5 deletions(-)
 create mode 100644 news/1335.bugfix

diff --git a/hydra/core/utils.py b/hydra/core/utils.py
index 3fc2ea35e4b..201703acd5c 100644
--- a/hydra/core/utils.py
+++ b/hydra/core/utils.py
@@ -86,8 +86,9 @@ def run_job(
     configure_logging: bool = True,
 ) -> "JobReturn":
     old_cwd = os.getcwd()
-    working_dir = str(OmegaConf.select(config, job_dir_key))
     orig_hydra_cfg = HydraConfig.instance().cfg
+    HydraConfig.instance().set_config(config)
+    working_dir = str(OmegaConf.select(config, job_dir_key))
     if job_subdir_key is not None:
         # evaluate job_subdir_key lazily.
         # this is running on the client side in sweep and contains things such as job:id which
@@ -98,15 +99,13 @@ def run_job(
         ret = JobReturn()
         ret.working_dir = working_dir
         task_cfg = copy.deepcopy(config)
-        hydra_cfg = OmegaConf.masked_copy(task_cfg, "hydra")
-        # maintain parent to preserve interpolation links from hydra_cfg to job_cfg
-        hydra_cfg._set_parent(task_cfg)
         with read_write(task_cfg):
             with open_dict(task_cfg):
                 del task_cfg["hydra"]
-        HydraConfig.instance().cfg = hydra_cfg  # type: ignore
 
         ret.cfg = task_cfg
+        hydra_cfg = copy.deepcopy(HydraConfig.instance().cfg)
+        assert isinstance(hydra_cfg, DictConfig)
         ret.hydra_cfg = hydra_cfg
         overrides = OmegaConf.to_container(config.hydra.overrides.task)
         assert isinstance(overrides, list)
diff --git a/news/1335.bugfix b/news/1335.bugfix
new file mode 100644
index 00000000000..08e85f3b4cb
--- /dev/null
+++ b/news/1335.bugfix
@@ -0,0 +1 @@
+Fix interpolation in Hydra config node
diff --git a/tests/test_hydra.py b/tests/test_hydra.py
index f1d7ef2cbc8..f8c6afa1dd4 100644
--- a/tests/test_hydra.py
+++ b/tests/test_hydra.py
@@ -1166,3 +1166,25 @@ def test_structured_with_none_list(monkeypatch: Any, tmpdir: Path) -> None:
     ]
     result, _err = get_run_output(cmd)
     assert result == "{'list': None}"
+
+
+def test_self_hydra_config_interpolation_integration(tmpdir: Path) -> None:
+    cfg = OmegaConf.create()
+    integration_test(
+        tmpdir=tmpdir,
+        task_config=cfg,
+        overrides=[],
+        prints="HydraConfig.get().job_logging.handlers.file.filename",
+        expected_outputs="task.log",
+    )
+
+
+def test_job_id_and_num_in_sweep(tmpdir: Path) -> None:
+    cfg = OmegaConf.create()
+    integration_test(
+        tmpdir=tmpdir,
+        task_config=cfg,
+        overrides=["-m"],
+        prints=["HydraConfig.get().job.id", "str(HydraConfig.get().job.num)"],
+        expected_outputs=["0", "0"],
+    )