test: Add yaml_file_get_provenance

Add a new helper - testutils.yaml_file_get_provenance, this will let us
make less fragile assertions about the presence of provenance in
BuildStream output.

2 files changed, 29 insertions, 0 deletions

diff --git a/tests/testutils/__init__.py b/tests/testutils/__init__.py
index 173cc7c3e..67378c959 100644
--- a/tests/testutils/__init__.py
+++ b/tests/testutils/__init__.py
@@ -29,3 +29,4 @@ from .element_generators import create_element_size, update_element_size
 from .junction import generate_junction
 from .runner_integration import wait_for_cache_granularity
 from .python_repo import setup_pypi_repo
+from .yaml import yaml_file_get_provenance
diff --git a/tests/testutils/yaml.py b/tests/testutils/yaml.py
new file mode 100644
index 000000000..4706a27bb
--- /dev/null
+++ b/tests/testutils/yaml.py
@@ -0,0 +1,28 @@
+from buildstream import _yaml
+
+
+# yaml_file_get_provenance()
+#
+# Load a yaml file and return it's _yaml.Provenance object.
+#
+# This is useful for checking the provenance in BuildStream output is as
+# expected.
+#
+# Args:
+#   path (str): The path to the file to be loaded
+#   shortname (str): How the path should appear in the error
+#   key (str): Optional key to look up in the loaded file
+#   indices (list of indexes): Optional index path, in the case of list values
+#
+# Returns:
+#   The Provenance of the dict, member or list element
+#
+def yaml_file_get_provenance(path, shortname, key=None, indices=None):
+    with open(path) as data:
+        element_yaml = _yaml.load_data(
+            data,
+            _yaml.ProvenanceFile(path, shortname, project=None),
+        )
+    provenance = _yaml.node_get_provenance(element_yaml, key, indices)
+    assert provenance is not None
+    return provenance