Make templated source tests available in buildstream.plugintestutils

39 files changed, 1649 insertions, 4 deletions

diff --git a/buildstream/plugintestutils/__init__.py b/buildstream/plugintestutils/__init__.py
index a052e4780..728a1fcce 100644
--- a/buildstream/plugintestutils/__init__.py
+++ b/buildstream/plugintestutils/__init__.py
@@ -15,8 +15,9 @@
 #  You should have received a copy of the GNU Lesser General Public
 #  License along with this library. If not, see <http://www.gnu.org/licenses/>.
 
+import os
 from collections import OrderedDict
-
+from . import _sourcetests
 from .repo import Repo
 from .runcli import cli, cli_integration, cli_remote_execution
 
@@ -89,5 +90,5 @@ def sourcetests_collection_hook(session):
     # Add the location of the source tests to the session's
     # python_files config. Without this, pytest may filter out these
     # tests during collection.
-    session.config.addinivalue_line("python_files", os.path.join(SOURCE_TESTS_PATH, "/**.py"))
+    session.config.addinivalue_line("python_files", os.path.join(SOURCE_TESTS_PATH, "*.py"))
     session.config.args.append(SOURCE_TESTS_PATH)
diff --git a/buildstream/plugintestutils/_sourcetests/__init__.py b/buildstream/plugintestutils/_sourcetests/__init__.py
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/__init__.py
diff --git a/buildstream/plugintestutils/_sourcetests/build_checkout.py b/buildstream/plugintestutils/_sourcetests/build_checkout.py
new file mode 100644
index 000000000..074be8429
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/build_checkout.py
@@ -0,0 +1,83 @@
+#
+#  Copyright (C) 2018 Codethink Limited
+#  Copyright (C) 2019 Bloomberg Finance LP
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# Pylint doesn't play well with fixtures and dependency injection from pytest
+# pylint: disable=redefined-outer-name
+
+import os
+import pytest
+
+from buildstream.plugintestutils import create_repo, ALL_REPO_KINDS
+from buildstream.plugintestutils import cli  # pylint: disable=unused-import
+from buildstream import _yaml
+
+# Project directory
+TOP_DIR = os.path.dirname(os.path.realpath(__file__))
+DATA_DIR = os.path.join(TOP_DIR, 'project')
+
+fetch_build_checkout_combos = \
+    [("strict", kind) for kind in ALL_REPO_KINDS] + \
+    [("non-strict", kind) for kind in ALL_REPO_KINDS]
+
+
+def strict_args(args, strict):
+    if strict != "strict":
+        return ['--no-strict', *args]
+    return args
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("strict,kind", fetch_build_checkout_combos)
+def test_fetch_build_checkout(cli, tmpdir, datafiles, strict, kind):
+    checkout = os.path.join(cli.directory, 'checkout')
+    project = str(datafiles)
+    dev_files_path = os.path.join(project, 'files', 'dev-files')
+    element_path = os.path.join(project, 'elements')
+    element_name = 'build-test-{}.bst'.format(kind)
+
+    # Create our repo object of the given source type with
+    # the dev files, and then collect the initial ref.
+    #
+    repo = create_repo(kind, str(tmpdir))
+    ref = repo.create(dev_files_path)
+
+    # Write out our test target
+    element = {
+        'kind': 'import',
+        'sources': [
+            repo.source_config(ref=ref)
+        ]
+    }
+    _yaml.dump(element,
+               os.path.join(element_path,
+                            element_name))
+
+    assert cli.get_element_state(project, element_name) == 'fetch needed'
+    result = cli.run(project=project, args=strict_args(['build', element_name], strict))
+    result.assert_success()
+    assert cli.get_element_state(project, element_name) == 'cached'
+
+    # Now check it out
+    result = cli.run(project=project, args=strict_args([
+        'artifact', 'checkout', element_name, '--directory', checkout
+    ], strict))
+    result.assert_success()
+
+    # Check that the pony.h include from files/dev-files exists
+    filename = os.path.join(checkout, 'usr', 'include', 'pony.h')
+    assert os.path.exists(filename)
diff --git a/buildstream/plugintestutils/_sourcetests/fetch.py b/buildstream/plugintestutils/_sourcetests/fetch.py
new file mode 100644
index 000000000..aaf92a14d
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/fetch.py
@@ -0,0 +1,107 @@
+#
+#  Copyright (C) 2018 Codethink Limited
+#  Copyright (C) 2019 Bloomberg Finance LP
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# Pylint doesn't play well with fixtures and dependency injection from pytest
+# pylint: disable=redefined-outer-name
+
+import os
+import pytest
+
+from buildstream import _yaml
+from .._utils import generate_junction, configure_project
+from .. import create_repo, ALL_REPO_KINDS
+from .. import cli  # pylint: disable=unused-import
+
+# Project directory
+TOP_DIR = os.path.dirname(os.path.realpath(__file__))
+DATA_DIR = os.path.join(TOP_DIR, 'project')
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_fetch(cli, tmpdir, datafiles, kind):
+    project = str(datafiles)
+    bin_files_path = os.path.join(project, 'files', 'bin-files')
+    element_path = os.path.join(project, 'elements')
+    element_name = 'fetch-test-{}.bst'.format(kind)
+
+    # Create our repo object of the given source type with
+    # the bin files, and then collect the initial ref.
+    #
+    repo = create_repo(kind, str(tmpdir))
+    ref = repo.create(bin_files_path)
+
+    # Write out our test target
+    element = {
+        'kind': 'import',
+        'sources': [
+            repo.source_config(ref=ref)
+        ]
+    }
+    _yaml.dump(element,
+               os.path.join(element_path,
+                            element_name))
+
+    # Assert that a fetch is needed
+    assert cli.get_element_state(project, element_name) == 'fetch needed'
+
+    # Now try to fetch it
+    result = cli.run(project=project, args=['source', 'fetch', element_name])
+    result.assert_success()
+
+    # Assert that we are now buildable because the source is
+    # now cached.
+    assert cli.get_element_state(project, element_name) == 'buildable'
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("ref_storage", [('inline'), ('project.refs')])
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_fetch_cross_junction(cli, tmpdir, datafiles, ref_storage, kind):
+    project = str(datafiles)
+    subproject_path = os.path.join(project, 'files', 'sub-project')
+    junction_path = os.path.join(project, 'elements', 'junction.bst')
+
+    import_etc_path = os.path.join(subproject_path, 'elements', 'import-etc-repo.bst')
+    etc_files_path = os.path.join(subproject_path, 'files', 'etc-files')
+
+    repo = create_repo(kind, str(tmpdir.join('import-etc')))
+    ref = repo.create(etc_files_path)
+
+    element = {
+        'kind': 'import',
+        'sources': [
+            repo.source_config(ref=(ref if ref_storage == 'inline' else None))
+        ]
+    }
+    _yaml.dump(element, import_etc_path)
+
+    configure_project(project, {
+        'ref-storage': ref_storage
+    })
+
+    generate_junction(tmpdir, subproject_path, junction_path, store_ref=(ref_storage == 'inline'))
+
+    if ref_storage == 'project.refs':
+        result = cli.run(project=project, args=['source', 'track', 'junction.bst'])
+        result.assert_success()
+        result = cli.run(project=project, args=['source', 'track', 'junction.bst:import-etc.bst'])
+        result.assert_success()
+
+    result = cli.run(project=project, args=['source', 'fetch', 'junction.bst:import-etc.bst'])
+    result.assert_success()
diff --git a/buildstream/plugintestutils/_sourcetests/mirror.py b/buildstream/plugintestutils/_sourcetests/mirror.py
new file mode 100644
index 000000000..d682bb2ef
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/mirror.py
@@ -0,0 +1,427 @@
+#
+#  Copyright (C) 2018 Codethink Limited
+#  Copyright (C) 2019 Bloomberg Finance LP
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# Pylint doesn't play well with fixtures and dependency injection from pytest
+# pylint: disable=redefined-outer-name
+
+import os
+import pytest
+
+from buildstream import _yaml
+from buildstream._exceptions import ErrorDomain
+from .._utils import generate_junction
+from .. import create_repo, ALL_REPO_KINDS
+from .. import cli  # pylint: disable=unused-import
+
+# Project directory
+TOP_DIR = os.path.dirname(os.path.realpath(__file__))
+DATA_DIR = os.path.join(TOP_DIR, 'project')
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_mirror_fetch(cli, tmpdir, datafiles, kind):
+    bin_files_path = os.path.join(str(datafiles), 'files', 'bin-files', 'usr')
+    dev_files_path = os.path.join(str(datafiles), 'files', 'dev-files', 'usr')
+    upstream_repodir = os.path.join(str(tmpdir), 'upstream')
+    mirror_repodir = os.path.join(str(tmpdir), 'mirror')
+    project_dir = os.path.join(str(tmpdir), 'project')
+    os.makedirs(project_dir)
+    element_dir = os.path.join(project_dir, 'elements')
+
+    # Create repo objects of the upstream and mirror
+    upstream_repo = create_repo(kind, upstream_repodir)
+    upstream_repo.create(bin_files_path)
+    mirror_repo = upstream_repo.copy(mirror_repodir)
+    upstream_ref = upstream_repo.create(dev_files_path)
+
+    element = {
+        'kind': 'import',
+        'sources': [
+            upstream_repo.source_config(ref=upstream_ref)
+        ]
+    }
+    element_name = 'test.bst'
+    element_path = os.path.join(element_dir, element_name)
+    full_repo = element['sources'][0]['url']
+    upstream_map, repo_name = os.path.split(full_repo)
+    alias = 'foo-' + kind
+    aliased_repo = alias + ':' + repo_name
+    element['sources'][0]['url'] = aliased_repo
+    full_mirror = mirror_repo.source_config()['url']
+    mirror_map, _ = os.path.split(full_mirror)
+    os.makedirs(element_dir)
+    _yaml.dump(element, element_path)
+
+    project = {
+        'name': 'test',
+        'element-path': 'elements',
+        'aliases': {
+            alias: upstream_map + "/"
+        },
+        'mirrors': [
+            {
+                'name': 'middle-earth',
+                'aliases': {
+                    alias: [mirror_map + "/"],
+                },
+            },
+        ]
+    }
+    project_file = os.path.join(project_dir, 'project.conf')
+    _yaml.dump(project, project_file)
+
+    # No obvious ways of checking that the mirror has been fetched
+    # But at least we can be sure it succeeds
+    result = cli.run(project=project_dir, args=['source', 'fetch', element_name])
+    result.assert_success()
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_mirror_fetch_upstream_absent(cli, tmpdir, datafiles, kind):
+    dev_files_path = os.path.join(str(datafiles), 'files', 'dev-files', 'usr')
+    upstream_repodir = os.path.join(str(tmpdir), 'upstream')
+    mirror_repodir = os.path.join(str(tmpdir), 'mirror')
+    project_dir = os.path.join(str(tmpdir), 'project')
+    os.makedirs(project_dir)
+    element_dir = os.path.join(project_dir, 'elements')
+
+    # Create repo objects of the upstream and mirror
+    upstream_repo = create_repo(kind, upstream_repodir)
+    ref = upstream_repo.create(dev_files_path)
+    mirror_repo = upstream_repo.copy(mirror_repodir)
+
+    element = {
+        'kind': 'import',
+        'sources': [
+            upstream_repo.source_config(ref=ref)
+        ]
+    }
+
+    element_name = 'test.bst'
+    element_path = os.path.join(element_dir, element_name)
+    full_repo = element['sources'][0]['url']
+    _, repo_name = os.path.split(full_repo)
+    alias = 'foo-' + kind
+    aliased_repo = alias + ':' + repo_name
+    element['sources'][0]['url'] = aliased_repo
+    full_mirror = mirror_repo.source_config()['url']
+    mirror_map, _ = os.path.split(full_mirror)
+    os.makedirs(element_dir)
+    _yaml.dump(element, element_path)
+
+    project = {
+        'name': 'test',
+        'element-path': 'elements',
+        'aliases': {
+            alias: 'http://www.example.com/'
+        },
+        'mirrors': [
+            {
+                'name': 'middle-earth',
+                'aliases': {
+                    alias: [mirror_map + "/"],
+                },
+            },
+        ]
+    }
+    project_file = os.path.join(project_dir, 'project.conf')
+    _yaml.dump(project, project_file)
+
+    result = cli.run(project=project_dir, args=['source', 'fetch', element_name])
+    result.assert_success()
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_mirror_from_includes(cli, tmpdir, datafiles, kind):
+    bin_files_path = os.path.join(str(datafiles), 'files', 'bin-files', 'usr')
+    upstream_repodir = os.path.join(str(tmpdir), 'upstream')
+    mirror_repodir = os.path.join(str(tmpdir), 'mirror')
+    project_dir = os.path.join(str(tmpdir), 'project')
+    os.makedirs(project_dir)
+    element_dir = os.path.join(project_dir, 'elements')
+
+    # Create repo objects of the upstream and mirror
+    upstream_repo = create_repo(kind, upstream_repodir)
+    upstream_ref = upstream_repo.create(bin_files_path)
+    mirror_repo = upstream_repo.copy(mirror_repodir)
+
+    element = {
+        'kind': 'import',
+        'sources': [
+            upstream_repo.source_config(ref=upstream_ref)
+        ]
+    }
+    element_name = 'test.bst'
+    element_path = os.path.join(element_dir, element_name)
+    full_repo = element['sources'][0]['url']
+    upstream_map, repo_name = os.path.split(full_repo)
+    alias = 'foo-' + kind
+    aliased_repo = alias + ':' + repo_name
+    element['sources'][0]['url'] = aliased_repo
+    full_mirror = mirror_repo.source_config()['url']
+    mirror_map, _ = os.path.split(full_mirror)
+    os.makedirs(element_dir)
+    _yaml.dump(element, element_path)
+
+    config_project_dir = str(tmpdir.join('config'))
+    os.makedirs(config_project_dir, exist_ok=True)
+    config_project = {
+        'name': 'config'
+    }
+    _yaml.dump(config_project, os.path.join(config_project_dir, 'project.conf'))
+    extra_mirrors = {
+        'mirrors': [
+            {
+                'name': 'middle-earth',
+                'aliases': {
+                    alias: [mirror_map + "/"],
+                }
+            }
+        ]
+    }
+    _yaml.dump(extra_mirrors, os.path.join(config_project_dir, 'mirrors.yml'))
+    generate_junction(str(tmpdir.join('config_repo')),
+                      config_project_dir,
+                      os.path.join(element_dir, 'config.bst'))
+
+    project = {
+        'name': 'test',
+        'element-path': 'elements',
+        'aliases': {
+            alias: upstream_map + "/"
+        },
+        '(@)': [
+            'config.bst:mirrors.yml'
+        ]
+    }
+    project_file = os.path.join(project_dir, 'project.conf')
+    _yaml.dump(project, project_file)
+
+    # Now make the upstream unavailable.
+    os.rename(upstream_repo.repo, '{}.bak'.format(upstream_repo.repo))
+    result = cli.run(project=project_dir, args=['source', 'fetch', element_name])
+    result.assert_success()
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_mirror_junction_from_includes(cli, tmpdir, datafiles, kind):
+    bin_files_path = os.path.join(str(datafiles), 'files', 'bin-files', 'usr')
+    upstream_repodir = os.path.join(str(tmpdir), 'upstream')
+    mirror_repodir = os.path.join(str(tmpdir), 'mirror')
+    project_dir = os.path.join(str(tmpdir), 'project')
+    os.makedirs(project_dir)
+    element_dir = os.path.join(project_dir, 'elements')
+
+    # Create repo objects of the upstream and mirror
+    upstream_repo = create_repo(kind, upstream_repodir)
+    upstream_ref = upstream_repo.create(bin_files_path)
+    mirror_repo = upstream_repo.copy(mirror_repodir)
+
+    element = {
+        'kind': 'junction',
+        'sources': [
+            upstream_repo.source_config(ref=upstream_ref)
+        ]
+    }
+    element_name = 'test.bst'
+    element_path = os.path.join(element_dir, element_name)
+    full_repo = element['sources'][0]['url']
+    upstream_map, repo_name = os.path.split(full_repo)
+    alias = 'foo-' + kind
+    aliased_repo = alias + ':' + repo_name
+    element['sources'][0]['url'] = aliased_repo
+    full_mirror = mirror_repo.source_config()['url']
+    mirror_map, _ = os.path.split(full_mirror)
+    os.makedirs(element_dir)
+    _yaml.dump(element, element_path)
+
+    config_project_dir = str(tmpdir.join('config'))
+    os.makedirs(config_project_dir, exist_ok=True)
+    config_project = {
+        'name': 'config'
+    }
+    _yaml.dump(config_project, os.path.join(config_project_dir, 'project.conf'))
+    extra_mirrors = {
+        'mirrors': [
+            {
+                'name': 'middle-earth',
+                'aliases': {
+                    alias: [mirror_map + "/"],
+                }
+            }
+        ]
+    }
+    _yaml.dump(extra_mirrors, os.path.join(config_project_dir, 'mirrors.yml'))
+    generate_junction(str(tmpdir.join('config_repo')),
+                      config_project_dir,
+                      os.path.join(element_dir, 'config.bst'))
+
+    project = {
+        'name': 'test',
+        'element-path': 'elements',
+        'aliases': {
+            alias: upstream_map + "/"
+        },
+        '(@)': [
+            'config.bst:mirrors.yml'
+        ]
+    }
+    project_file = os.path.join(project_dir, 'project.conf')
+    _yaml.dump(project, project_file)
+
+    # Now make the upstream unavailable.
+    os.rename(upstream_repo.repo, '{}.bak'.format(upstream_repo.repo))
+    result = cli.run(project=project_dir, args=['source', 'fetch', element_name])
+    result.assert_main_error(ErrorDomain.STREAM, None)
+    # Now make the upstream available again.
+    os.rename('{}.bak'.format(upstream_repo.repo), upstream_repo.repo)
+    result = cli.run(project=project_dir, args=['source', 'fetch', element_name])
+    result.assert_success()
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_mirror_track_upstream_present(cli, tmpdir, datafiles, kind):
+    bin_files_path = os.path.join(str(datafiles), 'files', 'bin-files', 'usr')
+    dev_files_path = os.path.join(str(datafiles), 'files', 'dev-files', 'usr')
+    upstream_repodir = os.path.join(str(tmpdir), 'upstream')
+    mirror_repodir = os.path.join(str(tmpdir), 'mirror')
+    project_dir = os.path.join(str(tmpdir), 'project')
+    os.makedirs(project_dir)
+    element_dir = os.path.join(project_dir, 'elements')
+
+    # Create repo objects of the upstream and mirror
+    upstream_repo = create_repo(kind, upstream_repodir)
+    upstream_repo.create(bin_files_path)
+    mirror_repo = upstream_repo.copy(mirror_repodir)
+    upstream_ref = upstream_repo.create(dev_files_path)
+
+    element = {
+        'kind': 'import',
+        'sources': [
+            upstream_repo.source_config(ref=upstream_ref)
+        ]
+    }
+
+    element_name = 'test.bst'
+    element_path = os.path.join(element_dir, element_name)
+    full_repo = element['sources'][0]['url']
+    upstream_map, repo_name = os.path.split(full_repo)
+    alias = 'foo-' + kind
+    aliased_repo = alias + ':' + repo_name
+    element['sources'][0]['url'] = aliased_repo
+    full_mirror = mirror_repo.source_config()['url']
+    mirror_map, _ = os.path.split(full_mirror)
+    os.makedirs(element_dir)
+    _yaml.dump(element, element_path)
+
+    project = {
+        'name': 'test',
+        'element-path': 'elements',
+        'aliases': {
+            alias: upstream_map + "/"
+        },
+        'mirrors': [
+            {
+                'name': 'middle-earth',
+                'aliases': {
+                    alias: [mirror_map + "/"],
+                },
+            },
+        ]
+    }
+    project_file = os.path.join(project_dir, 'project.conf')
+    _yaml.dump(project, project_file)
+
+    result = cli.run(project=project_dir, args=['source', 'track', element_name])
+    result.assert_success()
+
+    # Tracking tries upstream first. Check the ref is from upstream.
+    new_element = _yaml.load(element_path)
+    source = _yaml.node_get(new_element, dict, 'sources', [0])
+    if 'ref' in source:
+        assert _yaml.node_get(source, str, 'ref') == upstream_ref
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_mirror_track_upstream_absent(cli, tmpdir, datafiles, kind):
+    bin_files_path = os.path.join(str(datafiles), 'files', 'bin-files', 'usr')
+    dev_files_path = os.path.join(str(datafiles), 'files', 'dev-files', 'usr')
+    upstream_repodir = os.path.join(str(tmpdir), 'upstream')
+    mirror_repodir = os.path.join(str(tmpdir), 'mirror')
+    project_dir = os.path.join(str(tmpdir), 'project')
+    os.makedirs(project_dir)
+    element_dir = os.path.join(project_dir, 'elements')
+
+    # Create repo objects of the upstream and mirror
+    upstream_repo = create_repo(kind, upstream_repodir)
+    upstream_ref = upstream_repo.create(bin_files_path)
+    mirror_repo = upstream_repo.copy(mirror_repodir)
+    mirror_ref = upstream_ref
+    upstream_ref = upstream_repo.create(dev_files_path)
+
+    element = {
+        'kind': 'import',
+        'sources': [
+            upstream_repo.source_config(ref=upstream_ref)
+        ]
+    }
+
+    element_name = 'test.bst'
+    element_path = os.path.join(element_dir, element_name)
+    full_repo = element['sources'][0]['url']
+    _, repo_name = os.path.split(full_repo)
+    alias = 'foo-' + kind
+    aliased_repo = alias + ':' + repo_name
+    element['sources'][0]['url'] = aliased_repo
+    full_mirror = mirror_repo.source_config()['url']
+    mirror_map, _ = os.path.split(full_mirror)
+    os.makedirs(element_dir)
+    _yaml.dump(element, element_path)
+
+    project = {
+        'name': 'test',
+        'element-path': 'elements',
+        'aliases': {
+            alias: 'http://www.example.com/'
+        },
+        'mirrors': [
+            {
+                'name': 'middle-earth',
+                'aliases': {
+                    alias: [mirror_map + "/"],
+                },
+            },
+        ]
+    }
+    project_file = os.path.join(project_dir, 'project.conf')
+    _yaml.dump(project, project_file)
+
+    result = cli.run(project=project_dir, args=['source', 'track', element_name])
+    result.assert_success()
+
+    # Check that tracking fell back to the mirror
+    new_element = _yaml.load(element_path)
+    source = _yaml.node_get(new_element, dict, 'sources', [0])
+    if 'ref' in source:
+        assert _yaml.node_get(source, str, 'ref') == mirror_ref
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/base.bst b/buildstream/plugintestutils/_sourcetests/project/elements/base.bst
new file mode 100644
index 000000000..428afa736
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/base.bst
@@ -0,0 +1,5 @@
+# elements/base.bst
+
+kind: stack
+depends:
+  - base/base-alpine.bst
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/base/base-alpine.bst b/buildstream/plugintestutils/_sourcetests/project/elements/base/base-alpine.bst
new file mode 100644
index 000000000..c5833095d
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/base/base-alpine.bst
@@ -0,0 +1,17 @@
+kind: import
+
+description: |
+  Alpine Linux base for tests
+
+  Generated using the `tests/integration-tests/base/generate-base.sh` script.
+
+sources:
+  - kind: tar
+    base-dir: ''
+    (?):
+    - arch == "x86-64":
+        ref: 3eb559250ba82b64a68d86d0636a6b127aa5f6d25d3601a79f79214dc9703639
+        url: "alpine:integration-tests-base.v1.x86_64.tar.xz"
+    - arch == "aarch64":
+        ref: 431fb5362032ede6f172e70a3258354a8fd71fcbdeb1edebc0e20968c792329a
+        url: "alpine:integration-tests-base.v1.aarch64.tar.xz"
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/import-bin.bst b/buildstream/plugintestutils/_sourcetests/project/elements/import-bin.bst
new file mode 100644
index 000000000..a847c0c23
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/import-bin.bst
@@ -0,0 +1,4 @@
+kind: import
+sources:
+- kind: local
+  path: files/bin-files
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/import-dev.bst b/buildstream/plugintestutils/_sourcetests/project/elements/import-dev.bst
new file mode 100644
index 000000000..152a54667
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/import-dev.bst
@@ -0,0 +1,4 @@
+kind: import
+sources:
+- kind: local
+  path: files/dev-files
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/dependency/horsey.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/dependency/horsey.bst
new file mode 100644
index 000000000..bd1ffae9c
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/dependency/horsey.bst
@@ -0,0 +1,3 @@
+kind: autotools
+depends:
+  - multiple_targets/dependency/pony.bst
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/dependency/pony.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/dependency/pony.bst
new file mode 100644
index 000000000..3c29b4ea1
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/dependency/pony.bst
@@ -0,0 +1 @@
+kind: autotools
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/dependency/zebry.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/dependency/zebry.bst
new file mode 100644
index 000000000..98447ab52
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/dependency/zebry.bst
@@ -0,0 +1,3 @@
+kind: autotools
+depends:
+  - multiple_targets/dependency/horsey.bst
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/0.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/0.bst
new file mode 100644
index 000000000..a99be06a0
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/0.bst
@@ -0,0 +1,7 @@
+kind: autotools
+description: Root node
+depends:
+  - multiple_targets/order/2.bst
+  - multiple_targets/order/3.bst
+  - filename: multiple_targets/order/run.bst
+    type: runtime
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/1.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/1.bst
new file mode 100644
index 000000000..82b507a62
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/1.bst
@@ -0,0 +1,4 @@
+kind: autotools
+description: Root node
+depends:
+  - multiple_targets/order/9.bst
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/2.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/2.bst
new file mode 100644
index 000000000..ee1afae20
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/2.bst
@@ -0,0 +1,4 @@
+kind: autotools
+description: First dependency level
+depends:
+  - multiple_targets/order/3.bst
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/3.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/3.bst
new file mode 100644
index 000000000..4c3a23dab
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/3.bst
@@ -0,0 +1,6 @@
+kind: autotools
+description: Second dependency level
+depends:
+  - multiple_targets/order/4.bst
+  - multiple_targets/order/5.bst
+  - multiple_targets/order/6.bst
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/4.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/4.bst
new file mode 100644
index 000000000..b663a0b52
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/4.bst
@@ -0,0 +1,2 @@
+kind: autotools
+description: Third level dependency
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/5.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/5.bst
new file mode 100644
index 000000000..b9efcf71b
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/5.bst
@@ -0,0 +1,2 @@
+kind: autotools
+description: Fifth level dependency
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/6.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/6.bst
new file mode 100644
index 000000000..6c19d04e3
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/6.bst
@@ -0,0 +1,4 @@
+kind: autotools
+description: Fourth level dependency
+depends:
+  - multiple_targets/order/5.bst
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/7.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/7.bst
new file mode 100644
index 000000000..6805b3e6d
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/7.bst
@@ -0,0 +1,4 @@
+kind: autotools
+description: Third level dependency
+depends:
+  - multiple_targets/order/6.bst
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/8.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/8.bst
new file mode 100644
index 000000000..b8d8964a0
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/8.bst
@@ -0,0 +1,4 @@
+kind: autotools
+description: Second level dependency
+depends:
+  - multiple_targets/order/7.bst
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/9.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/9.bst
new file mode 100644
index 000000000..cc13bf3f0
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/9.bst
@@ -0,0 +1,4 @@
+kind: autotools
+description: First level dependency
+depends:
+  - multiple_targets/order/8.bst
diff --git a/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/run.bst b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/run.bst
new file mode 100644
index 000000000..9b3d2446c
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/elements/multiple_targets/order/run.bst
@@ -0,0 +1,2 @@
+kind: autotools
+description: Not a root node, yet built at the same time as root nodes
diff --git a/buildstream/plugintestutils/_sourcetests/project/files/bar b/buildstream/plugintestutils/_sourcetests/project/files/bar
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/files/bar
diff --git a/buildstream/plugintestutils/_sourcetests/project/files/bin-files/usr/bin/hello b/buildstream/plugintestutils/_sourcetests/project/files/bin-files/usr/bin/hello
new file mode 100755
index 000000000..f534a4083
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/files/bin-files/usr/bin/hello
@@ -0,0 +1,3 @@
+#!/bin/bash
+
+echo "Hello !"
diff --git a/buildstream/plugintestutils/_sourcetests/project/files/dev-files/usr/include/pony.h b/buildstream/plugintestutils/_sourcetests/project/files/dev-files/usr/include/pony.h
new file mode 100644
index 000000000..40bd0c2e7
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/files/dev-files/usr/include/pony.h
@@ -0,0 +1,12 @@
+#ifndef __PONY_H__
+#define __PONY_H__
+
+#define PONY_BEGIN "Once upon a time, there was a pony."
+#define PONY_END "And they lived happily ever after, the end."
+
+#define MAKE_PONY(story)  \
+  PONY_BEGIN \
+  story \
+  PONY_END
+
+#endif /* __PONY_H__ */
diff --git a/buildstream/plugintestutils/_sourcetests/project/files/etc-files/etc/buildstream/config b/buildstream/plugintestutils/_sourcetests/project/files/etc-files/etc/buildstream/config
new file mode 100644
index 000000000..04204c7c9
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/files/etc-files/etc/buildstream/config
@@ -0,0 +1 @@
+config
diff --git a/buildstream/plugintestutils/_sourcetests/project/files/foo b/buildstream/plugintestutils/_sourcetests/project/files/foo
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/files/foo
diff --git a/buildstream/plugintestutils/_sourcetests/project/files/source-bundle/llamas.txt b/buildstream/plugintestutils/_sourcetests/project/files/source-bundle/llamas.txt
new file mode 100644
index 000000000..f98b24871
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/files/source-bundle/llamas.txt
@@ -0,0 +1 @@
+llamas
diff --git a/buildstream/plugintestutils/_sourcetests/project/files/sub-project/elements/import-etc.bst b/buildstream/plugintestutils/_sourcetests/project/files/sub-project/elements/import-etc.bst
new file mode 100644
index 000000000..f0171990e
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/files/sub-project/elements/import-etc.bst
@@ -0,0 +1,4 @@
+kind: import
+sources:
+- kind: local
+  path: files/etc-files
diff --git a/buildstream/plugintestutils/_sourcetests/project/files/sub-project/files/etc-files/etc/animal.conf b/buildstream/plugintestutils/_sourcetests/project/files/sub-project/files/etc-files/etc/animal.conf
new file mode 100644
index 000000000..db8c36cba
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/files/sub-project/files/etc-files/etc/animal.conf
@@ -0,0 +1 @@
+animal=Pony
diff --git a/buildstream/plugintestutils/_sourcetests/project/files/sub-project/project.conf b/buildstream/plugintestutils/_sourcetests/project/files/sub-project/project.conf
new file mode 100644
index 000000000..bbb8414a3
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/files/sub-project/project.conf
@@ -0,0 +1,4 @@
+# Project config for frontend build test
+name: subtest
+
+element-path: elements
diff --git a/buildstream/plugintestutils/_sourcetests/project/project.conf b/buildstream/plugintestutils/_sourcetests/project/project.conf
new file mode 100644
index 000000000..05b68bfeb
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/project/project.conf
@@ -0,0 +1,27 @@
+# Project config for frontend build test
+name: test
+element-path: elements
+aliases:
+  alpine: https://bst-integration-test-images.ams3.cdn.digitaloceanspaces.com/
+  project_dir: file://{project_dir}
+options:
+  linux:
+    type: bool
+    description: Whether to expect a linux platform
+    default: True
+  arch:
+    type: arch
+    description: Current architecture
+    values:
+      - x86-64
+      - aarch64
+split-rules:
+  test:
+    - |
+      /tests
+    - |
+      /tests/*
+
+fatal-warnings:
+- bad-element-suffix
+- bad-characters-in-name
diff --git a/buildstream/plugintestutils/_sourcetests/source_determinism.py b/buildstream/plugintestutils/_sourcetests/source_determinism.py
new file mode 100644
index 000000000..8597a7072
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/source_determinism.py
@@ -0,0 +1,118 @@
+#
+#  Copyright (C) 2018 Codethink Limited
+#  Copyright (C) 2019 Bloomberg Finance LP
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# Pylint doesn't play well with fixtures and dependency injection from pytest
+# pylint: disable=redefined-outer-name
+
+import os
+import pytest
+
+from buildstream import _yaml
+from .._utils.site import HAVE_SANDBOX
+from .. import create_repo, ALL_REPO_KINDS
+from .. import cli  # pylint: disable=unused-import
+
+# Project directory
+TOP_DIR = os.path.dirname(os.path.realpath(__file__))
+DATA_DIR = os.path.join(TOP_DIR, 'project')
+
+
+def create_test_file(*path, mode=0o644, content='content\n'):
+    path = os.path.join(*path)
+    os.makedirs(os.path.dirname(path), exist_ok=True)
+    with open(path, 'w') as f:
+        f.write(content)
+        os.fchmod(f.fileno(), mode)
+
+
+def create_test_directory(*path, mode=0o644):
+    create_test_file(*path, '.keep', content='')
+    path = os.path.join(*path)
+    os.chmod(path, mode)
+
+
+@pytest.mark.integration
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("kind", ['local', *ALL_REPO_KINDS])
+@pytest.mark.skipif(not HAVE_SANDBOX, reason='Only available with a functioning sandbox')
+def test_deterministic_source_umask(cli, tmpdir, datafiles, kind):
+    project = str(datafiles)
+    element_name = 'list.bst'
+    element_path = os.path.join(project, 'elements', element_name)
+    repodir = os.path.join(str(tmpdir), 'repo')
+    sourcedir = os.path.join(project, 'source')
+
+    create_test_file(sourcedir, 'a.txt', mode=0o700)
+    create_test_file(sourcedir, 'b.txt', mode=0o755)
+    create_test_file(sourcedir, 'c.txt', mode=0o600)
+    create_test_file(sourcedir, 'd.txt', mode=0o400)
+    create_test_file(sourcedir, 'e.txt', mode=0o644)
+    create_test_file(sourcedir, 'f.txt', mode=0o4755)
+    create_test_file(sourcedir, 'g.txt', mode=0o2755)
+    create_test_file(sourcedir, 'h.txt', mode=0o1755)
+    create_test_directory(sourcedir, 'dir-a', mode=0o0700)
+    create_test_directory(sourcedir, 'dir-c', mode=0o0755)
+    create_test_directory(sourcedir, 'dir-d', mode=0o4755)
+    create_test_directory(sourcedir, 'dir-e', mode=0o2755)
+    create_test_directory(sourcedir, 'dir-f', mode=0o1755)
+
+    if kind == 'local':
+        source = {'kind': 'local',
+                  'path': 'source'}
+    else:
+        repo = create_repo(kind, repodir)
+        ref = repo.create(sourcedir)
+        source = repo.source_config(ref=ref)
+    element = {
+        'kind': 'manual',
+        'depends': [
+            {
+                'filename': 'base.bst',
+                'type': 'build'
+            }
+        ],
+        'sources': [
+            source
+        ],
+        'config': {
+            'install-commands': [
+                'ls -l >"%{install-root}/ls-l"'
+            ]
+        }
+    }
+    _yaml.dump(element, element_path)
+
+    def get_value_for_umask(umask):
+        checkoutdir = os.path.join(str(tmpdir), 'checkout-{}'.format(umask))
+
+        old_umask = os.umask(umask)
+
+        try:
+            result = cli.run(project=project, args=['build', element_name])
+            result.assert_success()
+
+            result = cli.run(project=project, args=['artifact', 'checkout', element_name, '--directory', checkoutdir])
+            result.assert_success()
+
+            with open(os.path.join(checkoutdir, 'ls-l'), 'r') as f:
+                return f.read()
+        finally:
+            os.umask(old_umask)
+            cli.remove_artifact_from_cache(project, element_name)
+
+    assert get_value_for_umask(0o022) == get_value_for_umask(0o077)
diff --git a/buildstream/plugintestutils/_sourcetests/track.py b/buildstream/plugintestutils/_sourcetests/track.py
new file mode 100644
index 000000000..668ea29e5
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/track.py
@@ -0,0 +1,420 @@
+#
+#  Copyright (C) 2018 Codethink Limited
+#  Copyright (C) 2019 Bloomberg Finance LP
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# Pylint doesn't play well with fixtures and dependency injection from pytest
+# pylint: disable=redefined-outer-name
+
+import os
+import pytest
+
+from buildstream import _yaml
+from buildstream._exceptions import ErrorDomain
+from .._utils import generate_junction, configure_project
+from .. import create_repo, ALL_REPO_KINDS
+from .. import cli  # pylint: disable=unused-import
+
+# Project directory
+TOP_DIR = os.path.dirname(os.path.realpath(__file__))
+DATA_DIR = os.path.join(TOP_DIR, 'project')
+
+
+def generate_element(repo, element_path, dep_name=None):
+    element = {
+        'kind': 'import',
+        'sources': [
+            repo.source_config()
+        ]
+    }
+    if dep_name:
+        element['depends'] = [dep_name]
+
+    _yaml.dump(element, element_path)
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("ref_storage", [('inline'), ('project.refs')])
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_track(cli, tmpdir, datafiles, ref_storage, kind):
+    project = str(datafiles)
+    dev_files_path = os.path.join(project, 'files', 'dev-files')
+    element_path = os.path.join(project, 'elements')
+    element_name = 'track-test-{}.bst'.format(kind)
+
+    configure_project(project, {
+        'ref-storage': ref_storage
+    })
+
+    # Create our repo object of the given source type with
+    # the dev files, and then collect the initial ref.
+    #
+    repo = create_repo(kind, str(tmpdir))
+    repo.create(dev_files_path)
+
+    # Generate the element
+    generate_element(repo, os.path.join(element_path, element_name))
+
+    # Assert that a fetch is needed
+    assert cli.get_element_state(project, element_name) == 'no reference'
+
+    # Now first try to track it
+    result = cli.run(project=project, args=['source', 'track', element_name])
+    result.assert_success()
+
+    # And now fetch it: The Source has probably already cached the
+    # latest ref locally, but it is not required to have cached
+    # the associated content of the latest ref at track time, that
+    # is the job of fetch.
+    result = cli.run(project=project, args=['source', 'fetch', element_name])
+    result.assert_success()
+
+    # Assert that we are now buildable because the source is
+    # now cached.
+    assert cli.get_element_state(project, element_name) == 'buildable'
+
+    # Assert there was a project.refs created, depending on the configuration
+    if ref_storage == 'project.refs':
+        assert os.path.exists(os.path.join(project, 'project.refs'))
+    else:
+        assert not os.path.exists(os.path.join(project, 'project.refs'))
+
+
+# NOTE:
+#
+#    This test checks that recursive tracking works by observing
+#    element states after running a recursive tracking operation.
+#
+#    However, this test is ALSO valuable as it stresses the source
+#    plugins in a situation where many source plugins are operating
+#    at once on the same backing repository.
+#
+#    Do not change this test to use a separate 'Repo' per element
+#    as that would defeat the purpose of the stress test, otherwise
+#    please refactor that aspect into another test.
+#
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("amount", [(1), (10)])
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_track_recurse(cli, tmpdir, datafiles, kind, amount):
+    project = str(datafiles)
+    dev_files_path = os.path.join(project, 'files', 'dev-files')
+    element_path = os.path.join(project, 'elements')
+
+    # Try to actually launch as many fetch jobs as possible at the same time
+    #
+    # This stresses the Source plugins and helps to ensure that
+    # they handle concurrent access to the store correctly.
+    cli.configure({
+        'scheduler': {
+            'fetchers': amount,
+        }
+    })
+
+    # Create our repo object of the given source type with
+    # the dev files, and then collect the initial ref.
+    #
+    repo = create_repo(kind, str(tmpdir))
+    repo.create(dev_files_path)
+
+    # Write out our test targets
+    element_names = []
+    last_element_name = None
+    for i in range(amount + 1):
+        element_name = 'track-test-{}-{}.bst'.format(kind, i + 1)
+        filename = os.path.join(element_path, element_name)
+
+        element_names.append(element_name)
+
+        generate_element(repo, filename, dep_name=last_element_name)
+        last_element_name = element_name
+
+    # Assert that a fetch is needed
+    states = cli.get_element_states(project, [last_element_name])
+    for element_name in element_names:
+        assert states[element_name] == 'no reference'
+
+    # Now first try to track it
+    result = cli.run(project=project, args=[
+        'source', 'track', '--deps', 'all',
+        last_element_name])
+    result.assert_success()
+
+    # And now fetch it: The Source has probably already cached the
+    # latest ref locally, but it is not required to have cached
+    # the associated content of the latest ref at track time, that
+    # is the job of fetch.
+    result = cli.run(project=project, args=[
+        'source', 'fetch', '--deps', 'all',
+        last_element_name])
+    result.assert_success()
+
+    # Assert that the base is buildable and the rest are waiting
+    states = cli.get_element_states(project, [last_element_name])
+    for element_name in element_names:
+        if element_name == element_names[0]:
+            assert states[element_name] == 'buildable'
+        else:
+            assert states[element_name] == 'waiting'
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_track_recurse_except(cli, tmpdir, datafiles, kind):
+    project = str(datafiles)
+    dev_files_path = os.path.join(project, 'files', 'dev-files')
+    element_path = os.path.join(project, 'elements')
+    element_dep_name = 'track-test-dep-{}.bst'.format(kind)
+    element_target_name = 'track-test-target-{}.bst'.format(kind)
+
+    # Create our repo object of the given source type with
+    # the dev files, and then collect the initial ref.
+    #
+    repo = create_repo(kind, str(tmpdir))
+    repo.create(dev_files_path)
+
+    # Write out our test targets
+    generate_element(repo, os.path.join(element_path, element_dep_name))
+    generate_element(repo, os.path.join(element_path, element_target_name),
+                     dep_name=element_dep_name)
+
+    # Assert that a fetch is needed
+    states = cli.get_element_states(project, [element_target_name])
+    assert states[element_dep_name] == 'no reference'
+    assert states[element_target_name] == 'no reference'
+
+    # Now first try to track it
+    result = cli.run(project=project, args=[
+        'source', 'track', '--deps', 'all', '--except', element_dep_name,
+        element_target_name])
+    result.assert_success()
+
+    # And now fetch it: The Source has probably already cached the
+    # latest ref locally, but it is not required to have cached
+    # the associated content of the latest ref at track time, that
+    # is the job of fetch.
+    result = cli.run(project=project, args=[
+        'source', 'fetch', '--deps', 'none',
+        element_target_name])
+    result.assert_success()
+
+    # Assert that the dependency is buildable and the target is waiting
+    states = cli.get_element_states(project, [element_target_name])
+    assert states[element_dep_name] == 'no reference'
+    assert states[element_target_name] == 'waiting'
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("ref_storage", [('inline'), ('project.refs')])
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_cross_junction(cli, tmpdir, datafiles, ref_storage, kind):
+    project = str(datafiles)
+    subproject_path = os.path.join(project, 'files', 'sub-project')
+    junction_path = os.path.join(project, 'elements', 'junction.bst')
+    etc_files = os.path.join(subproject_path, 'files', 'etc-files')
+    repo_element_path = os.path.join(subproject_path, 'elements',
+                                     'import-etc-repo.bst')
+
+    configure_project(project, {
+        'ref-storage': ref_storage
+    })
+
+    repo = create_repo(kind, str(tmpdir.join('element_repo')))
+    repo.create(etc_files)
+
+    generate_element(repo, repo_element_path)
+
+    generate_junction(str(tmpdir.join('junction_repo')),
+                      subproject_path, junction_path, store_ref=False)
+
+    # Track the junction itself first.
+    result = cli.run(project=project, args=['source', 'track', 'junction.bst'])
+    result.assert_success()
+
+    assert cli.get_element_state(project, 'junction.bst:import-etc-repo.bst') == 'no reference'
+
+    # Track the cross junction element. -J is not given, it is implied.
+    result = cli.run(project=project, args=['source', 'track', 'junction.bst:import-etc-repo.bst'])
+
+    if ref_storage == 'inline':
+        # This is not allowed to track cross junction without project.refs.
+        result.assert_main_error(ErrorDomain.PIPELINE, 'untrackable-sources')
+    else:
+        result.assert_success()
+
+        assert cli.get_element_state(project, 'junction.bst:import-etc-repo.bst') == 'buildable'
+
+        assert os.path.exists(os.path.join(project, 'project.refs'))
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("ref_storage", [('inline'), ('project.refs')])
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_track_include(cli, tmpdir, datafiles, ref_storage, kind):
+    project = str(datafiles)
+    dev_files_path = os.path.join(project, 'files', 'dev-files')
+    element_path = os.path.join(project, 'elements')
+    element_name = 'track-test-{}.bst'.format(kind)
+
+    configure_project(project, {
+        'ref-storage': ref_storage
+    })
+
+    # Create our repo object of the given source type with
+    # the dev files, and then collect the initial ref.
+    #
+    repo = create_repo(kind, str(tmpdir))
+    ref = repo.create(dev_files_path)
+
+    # Generate the element
+    element = {
+        'kind': 'import',
+        '(@)': ['elements/sources.yml']
+    }
+    sources = {
+        'sources': [
+            repo.source_config()
+        ]
+    }
+
+    _yaml.dump(element, os.path.join(element_path, element_name))
+    _yaml.dump(sources, os.path.join(element_path, 'sources.yml'))
+
+    # Assert that a fetch is needed
+    assert cli.get_element_state(project, element_name) == 'no reference'
+
+    # Now first try to track it
+    result = cli.run(project=project, args=['source', 'track', element_name])
+    result.assert_success()
+
+    # And now fetch it: The Source has probably already cached the
+    # latest ref locally, but it is not required to have cached
+    # the associated content of the latest ref at track time, that
+    # is the job of fetch.
+    result = cli.run(project=project, args=['source', 'fetch', element_name])
+    result.assert_success()
+
+    # Assert that we are now buildable because the source is
+    # now cached.
+    assert cli.get_element_state(project, element_name) == 'buildable'
+
+    # Assert there was a project.refs created, depending on the configuration
+    if ref_storage == 'project.refs':
+        assert os.path.exists(os.path.join(project, 'project.refs'))
+    else:
+        assert not os.path.exists(os.path.join(project, 'project.refs'))
+
+        new_sources = _yaml.load(os.path.join(element_path, 'sources.yml'))
+
+        # Get all of the sources
+        assert 'sources' in new_sources
+        sources_list = _yaml.node_get(new_sources, list, 'sources')
+        assert len(sources_list) == 1
+
+        # Get the first source from the sources list
+        new_source = _yaml.node_get(new_sources, dict, 'sources', indices=[0])
+        assert 'ref' in new_source
+        assert ref == _yaml.node_get(new_source, str, 'ref')
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("ref_storage", [('inline'), ('project.refs')])
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_track_include_junction(cli, tmpdir, datafiles, ref_storage, kind):
+    project = str(datafiles)
+    dev_files_path = os.path.join(project, 'files', 'dev-files')
+    element_path = os.path.join(project, 'elements')
+    element_name = 'track-test-{}.bst'.format(kind)
+    subproject_path = os.path.join(project, 'files', 'sub-project')
+    sub_element_path = os.path.join(subproject_path, 'elements')
+    junction_path = os.path.join(element_path, 'junction.bst')
+
+    configure_project(project, {
+        'ref-storage': ref_storage
+    })
+
+    # Create our repo object of the given source type with
+    # the dev files, and then collect the initial ref.
+    #
+    repo = create_repo(kind, str(tmpdir.join('element_repo')))
+    repo.create(dev_files_path)
+
+    # Generate the element
+    element = {
+        'kind': 'import',
+        '(@)': ['junction.bst:elements/sources.yml']
+    }
+    sources = {
+        'sources': [
+            repo.source_config()
+        ]
+    }
+
+    _yaml.dump(element, os.path.join(element_path, element_name))
+    _yaml.dump(sources, os.path.join(sub_element_path, 'sources.yml'))
+
+    generate_junction(str(tmpdir.join('junction_repo')),
+                      subproject_path, junction_path, store_ref=True)
+
+    result = cli.run(project=project, args=['source', 'track', 'junction.bst'])
+    result.assert_success()
+
+    # Assert that a fetch is needed
+    assert cli.get_element_state(project, element_name) == 'no reference'
+
+    # Now first try to track it
+    result = cli.run(project=project, args=['source', 'track', element_name])
+
+    # Assert there was a project.refs created, depending on the configuration
+    if ref_storage == 'inline':
+        # FIXME: We should expect an error. But only a warning is emitted
+        # result.assert_main_error(ErrorDomain.SOURCE, 'tracking-junction-fragment')
+
+        assert 'junction.bst:elements/sources.yml: Cannot track source in a fragment from a junction' in result.stderr
+    else:
+        assert os.path.exists(os.path.join(project, 'project.refs'))
+
+        # And now fetch it: The Source has probably already cached the
+        # latest ref locally, but it is not required to have cached
+        # the associated content of the latest ref at track time, that
+        # is the job of fetch.
+        result = cli.run(project=project, args=['source', 'fetch', element_name])
+        result.assert_success()
+
+        # Assert that we are now buildable because the source is
+        # now cached.
+        assert cli.get_element_state(project, element_name) == 'buildable'
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("ref_storage", [('inline'), ('project.refs')])
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_track_junction_included(cli, tmpdir, datafiles, ref_storage, kind):
+    project = str(datafiles)
+    element_path = os.path.join(project, 'elements')
+    subproject_path = os.path.join(project, 'files', 'sub-project')
+    junction_path = os.path.join(element_path, 'junction.bst')
+
+    configure_project(project, {
+        'ref-storage': ref_storage,
+        '(@)': ['junction.bst:test.yml']
+    })
+
+    generate_junction(str(tmpdir.join('junction_repo')),
+                      subproject_path, junction_path, store_ref=False)
+
+    result = cli.run(project=project, args=['source', 'track', 'junction.bst'])
+    result.assert_success()
diff --git a/buildstream/plugintestutils/_sourcetests/track_cross_junction.py b/buildstream/plugintestutils/_sourcetests/track_cross_junction.py
new file mode 100644
index 000000000..ece3e0b8f
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/track_cross_junction.py
@@ -0,0 +1,186 @@
+#
+#  Copyright (C) 2018 Codethink Limited
+#  Copyright (C) 2019 Bloomberg Finance LP
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# Pylint doesn't play well with fixtures and dependency injection from pytest
+# pylint: disable=redefined-outer-name
+
+import os
+import pytest
+
+from buildstream import _yaml
+from .._utils import generate_junction
+from .. import create_repo, ALL_REPO_KINDS
+from .. import cli  # pylint: disable=unused-import
+
+# Project directory
+TOP_DIR = os.path.dirname(os.path.realpath(__file__))
+DATA_DIR = os.path.join(TOP_DIR, 'project')
+
+
+def generate_element(repo, element_path, dep_name=None):
+    element = {
+        'kind': 'import',
+        'sources': [
+            repo.source_config()
+        ]
+    }
+    if dep_name:
+        element['depends'] = [dep_name]
+
+    _yaml.dump(element, element_path)
+
+
+def generate_import_element(tmpdir, kind, project, name):
+    element_name = 'import-{}.bst'.format(name)
+    repo_element_path = os.path.join(project, 'elements', element_name)
+    files = str(tmpdir.join("imported_files_{}".format(name)))
+    os.makedirs(files)
+
+    with open(os.path.join(files, '{}.txt'.format(name)), 'w') as f:
+        f.write(name)
+
+    repo = create_repo(kind, str(tmpdir.join('element_{}_repo'.format(name))))
+    repo.create(files)
+
+    generate_element(repo, repo_element_path)
+
+    return element_name
+
+
+def generate_project(tmpdir, name, config=None):
+    if config is None:
+        config = {}
+
+    project_name = 'project-{}'.format(name)
+    subproject_path = os.path.join(str(tmpdir.join(project_name)))
+    os.makedirs(os.path.join(subproject_path, 'elements'))
+
+    project_conf = {
+        'name': name,
+        'element-path': 'elements'
+    }
+    project_conf.update(config)
+    _yaml.dump(project_conf, os.path.join(subproject_path, 'project.conf'))
+
+    return project_name, subproject_path
+
+
+def generate_simple_stack(project, name, dependencies):
+    element_name = '{}.bst'.format(name)
+    element_path = os.path.join(project, 'elements', element_name)
+    element = {
+        'kind': 'stack',
+        'depends': dependencies
+    }
+    _yaml.dump(element, element_path)
+
+    return element_name
+
+
+def generate_cross_element(project, subproject_name, import_name):
+    basename, _ = os.path.splitext(import_name)
+    return generate_simple_stack(project, 'import-{}-{}'.format(subproject_name, basename),
+                                 [{
+                                     'junction': '{}.bst'.format(subproject_name),
+                                     'filename': import_name
+                                 }])
+
+
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_cross_junction_multiple_projects(cli, tmpdir, kind):
+    tmpdir = tmpdir.join(kind)
+
+    # Generate 3 projects: main, a, b
+    _, project = generate_project(tmpdir, 'main', {'ref-storage': 'project.refs'})
+    project_a, project_a_path = generate_project(tmpdir, 'a')
+    project_b, project_b_path = generate_project(tmpdir, 'b')
+
+    # Generate an element with a trackable source for each project
+    element_a = generate_import_element(tmpdir, kind, project_a_path, 'a')
+    element_b = generate_import_element(tmpdir, kind, project_b_path, 'b')
+    element_c = generate_import_element(tmpdir, kind, project, 'c')
+
+    # Create some indirections to the elements with dependencies to test --deps
+    stack_a = generate_simple_stack(project_a_path, 'stack-a', [element_a])
+    stack_b = generate_simple_stack(project_b_path, 'stack-b', [element_b])
+
+    # Create junctions for projects a and b in main.
+    junction_a = '{}.bst'.format(project_a)
+    junction_a_path = os.path.join(project, 'elements', junction_a)
+    generate_junction(tmpdir.join('repo_a'), project_a_path, junction_a_path, store_ref=False)
+
+    junction_b = '{}.bst'.format(project_b)
+    junction_b_path = os.path.join(project, 'elements', junction_b)
+    generate_junction(tmpdir.join('repo_b'), project_b_path, junction_b_path, store_ref=False)
+
+    # Track the junctions.
+    result = cli.run(project=project, args=['source', 'track', junction_a, junction_b])
+    result.assert_success()
+
+    # Import elements from a and b in to main.
+    imported_a = generate_cross_element(project, project_a, stack_a)
+    imported_b = generate_cross_element(project, project_b, stack_b)
+
+    # Generate a top level stack depending on everything
+    all_bst = generate_simple_stack(project, 'all', [imported_a, imported_b, element_c])
+
+    # Track without following junctions. But explicitly also track the elements in project a.
+    result = cli.run(project=project, args=['source', 'track',
+                                            '--deps', 'all',
+                                            all_bst,
+                                            '{}:{}'.format(junction_a, stack_a)])
+    result.assert_success()
+
+    # Elements in project b should not be tracked. But elements in project a and main should.
+    expected = [element_c,
+                '{}:{}'.format(junction_a, element_a)]
+    assert set(result.get_tracked_elements()) == set(expected)
+
+
+@pytest.mark.parametrize("kind", [(kind) for kind in ALL_REPO_KINDS])
+def test_track_exceptions(cli, tmpdir, kind):
+    tmpdir = tmpdir.join(kind)
+
+    _, project = generate_project(tmpdir, 'main', {'ref-storage': 'project.refs'})
+    project_a, project_a_path = generate_project(tmpdir, 'a')
+
+    element_a = generate_import_element(tmpdir, kind, project_a_path, 'a')
+    element_b = generate_import_element(tmpdir, kind, project_a_path, 'b')
+
+    all_bst = generate_simple_stack(project_a_path, 'all', [element_a,
+                                                            element_b])
+
+    junction_a = '{}.bst'.format(project_a)
+    junction_a_path = os.path.join(project, 'elements', junction_a)
+    generate_junction(tmpdir.join('repo_a'), project_a_path, junction_a_path, store_ref=False)
+
+    result = cli.run(project=project, args=['source', 'track', junction_a])
+    result.assert_success()
+
+    imported_b = generate_cross_element(project, project_a, element_b)
+    indirection = generate_simple_stack(project, 'indirection', [imported_b])
+
+    result = cli.run(project=project,
+                     args=['source', 'track', '--deps', 'all',
+                           '--except', indirection,
+                           '{}:{}'.format(junction_a, all_bst), imported_b])
+    result.assert_success()
+
+    expected = ['{}:{}'.format(junction_a, element_a),
+                '{}:{}'.format(junction_a, element_b)]
+    assert set(result.get_tracked_elements()) == set(expected)
diff --git a/buildstream/plugintestutils/_sourcetests/workspace.py b/buildstream/plugintestutils/_sourcetests/workspace.py
new file mode 100644
index 000000000..5218f8f1e
--- /dev/null
+++ b/buildstream/plugintestutils/_sourcetests/workspace.py
@@ -0,0 +1,161 @@
+#
+#  Copyright (C) 2018 Codethink Limited
+#  Copyright (C) 2019 Bloomberg Finance LP
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# Pylint doesn't play well with fixtures and dependency injection from pytest
+# pylint: disable=redefined-outer-name
+
+import os
+import shutil
+import pytest
+
+from buildstream import _yaml
+from .. import create_repo, ALL_REPO_KINDS
+from .. import cli  # pylint: disable=unused-import
+
+# Project directory
+TOP_DIR = os.path.dirname(os.path.realpath(__file__))
+DATA_DIR = os.path.join(TOP_DIR, 'project')
+
+
+class WorkspaceCreator():
+    def __init__(self, cli, tmpdir, datafiles, project_path=None):
+        self.cli = cli
+        self.tmpdir = tmpdir
+        self.datafiles = datafiles
+
+        if not project_path:
+            project_path = str(datafiles)
+        else:
+            shutil.copytree(str(datafiles), project_path)
+
+        self.project_path = project_path
+        self.bin_files_path = os.path.join(project_path, 'files', 'bin-files')
+
+        self.workspace_cmd = os.path.join(self.project_path, 'workspace_cmd')
+
+    def create_workspace_element(self, kind, track, suffix='', workspace_dir=None,
+                                 element_attrs=None):
+        element_name = 'workspace-test-{}{}.bst'.format(kind, suffix)
+        element_path = os.path.join(self.project_path, 'elements')
+        if not workspace_dir:
+            workspace_dir = os.path.join(self.workspace_cmd, element_name)
+            if workspace_dir[-4:] == '.bst':
+                workspace_dir = workspace_dir[:-4]
+
+        # Create our repo object of the given source type with
+        # the bin files, and then collect the initial ref.
+        repo = create_repo(kind, str(self.tmpdir))
+        ref = repo.create(self.bin_files_path)
+        if track:
+            ref = None
+
+        # Write out our test target
+        element = {
+            'kind': 'import',
+            'sources': [
+                repo.source_config(ref=ref)
+            ]
+        }
+        if element_attrs:
+            element = {**element, **element_attrs}
+        _yaml.dump(element,
+                   os.path.join(element_path,
+                                element_name))
+        return element_name, element_path, workspace_dir
+
+    def create_workspace_elements(self, kinds, track, suffixs=None, workspace_dir_usr=None,
+                                  element_attrs=None):
+
+        element_tuples = []
+
+        if suffixs is None:
+            suffixs = ['', ] * len(kinds)
+        else:
+            if len(suffixs) != len(kinds):
+                raise "terable error"
+
+        for suffix, kind in zip(suffixs, kinds):
+            element_name, _, workspace_dir = \
+                self.create_workspace_element(kind, track, suffix, workspace_dir_usr,
+                                              element_attrs)
+            element_tuples.append((element_name, workspace_dir))
+
+        # Assert that there is no reference, a track & fetch is needed
+        states = self.cli.get_element_states(self.project_path, [
+            e for e, _ in element_tuples
+        ])
+        if track:
+            assert not any(states[e] != 'no reference' for e, _ in element_tuples)
+        else:
+            assert not any(states[e] != 'fetch needed' for e, _ in element_tuples)
+
+        return element_tuples
+
+    def open_workspaces(self, kinds, track, suffixs=None, workspace_dir=None,
+                        element_attrs=None, no_checkout=False):
+
+        element_tuples = self.create_workspace_elements(kinds, track, suffixs, workspace_dir,
+                                                        element_attrs)
+        os.makedirs(self.workspace_cmd, exist_ok=True)
+
+        # Now open the workspace, this should have the effect of automatically
+        # tracking & fetching the source from the repo.
+        args = ['workspace', 'open']
+        if track:
+            args.append('--track')
+        if no_checkout:
+            args.append('--no-checkout')
+        if workspace_dir is not None:
+            assert len(element_tuples) == 1, "test logic error"
+            _, workspace_dir = element_tuples[0]
+            args.extend(['--directory', workspace_dir])
+
+        args.extend([element_name for element_name, workspace_dir_suffix in element_tuples])
+        result = self.cli.run(cwd=self.workspace_cmd, project=self.project_path, args=args)
+
+        result.assert_success()
+
+        if not no_checkout:
+            # Assert that we are now buildable because the source is now cached.
+            states = self.cli.get_element_states(self.project_path, [
+                e for e, _ in element_tuples
+            ])
+            assert not any(states[e] != 'buildable' for e, _ in element_tuples)
+
+            # Check that the executable hello file is found in each workspace
+            for _, workspace in element_tuples:
+                filename = os.path.join(workspace, 'usr', 'bin', 'hello')
+                assert os.path.exists(filename)
+
+        return element_tuples
+
+
+def open_workspace(cli, tmpdir, datafiles, kind, track, suffix='', workspace_dir=None,
+                   project_path=None, element_attrs=None, no_checkout=False):
+    workspace_object = WorkspaceCreator(cli, tmpdir, datafiles, project_path)
+    workspaces = workspace_object.open_workspaces((kind, ), track, (suffix, ), workspace_dir,
+                                                  element_attrs, no_checkout)
+    assert len(workspaces) == 1
+    element_name, workspace = workspaces[0]
+    return element_name, workspace_object.project_path, workspace
+
+
+@pytest.mark.datafiles(DATA_DIR)
+@pytest.mark.parametrize("kind", ALL_REPO_KINDS)
+def test_open(cli, tmpdir, datafiles, kind):
+    open_workspace(cli, tmpdir, datafiles, kind, False)
diff --git a/buildstream/plugintestutils/_utils/__init__.py b/buildstream/plugintestutils/_utils/__init__.py
index 5938e6a5e..b419d72b7 100644
--- a/buildstream/plugintestutils/_utils/__init__.py
+++ b/buildstream/plugintestutils/_utils/__init__.py
@@ -1 +1,10 @@
+import os
+
+from buildstream import _yaml
 from .junction import generate_junction
+
+
+def configure_project(path, config):
+    config['name'] = 'test'
+    config['element-path'] = 'elements'
+    _yaml.dump(config, os.path.join(path, 'project.conf'))
diff --git a/buildstream/plugintestutils/_utils/junction.py b/buildstream/plugintestutils/_utils/junction.py
index 530a191ac..ca059eb8b 100644
--- a/buildstream/plugintestutils/_utils/junction.py
+++ b/buildstream/plugintestutils/_utils/junction.py
@@ -1,9 +1,9 @@
 import subprocess
 import pytest
 
-from .._utils.site import HAVE_GIT, GIT, GIT_ENV
-from buildstream.plugintestutils import Repo
 from buildstream import _yaml
+from .. import Repo
+from .site import HAVE_GIT, GIT, GIT_ENV
 
 
 # generate_junction()