Merge branch 'tiagogomes/issue-195' into 'master'Qinusty/490-artifact-cache-interactivity

Add validation for project paths

See merge request BuildStream/buildstream!593

30 files changed, 492 insertions, 139 deletions

diff --git a/.pylintrc b/.pylintrc
index 93f9eeadf..153a9ef3e 100644
--- a/.pylintrc
+++ b/.pylintrc
@@ -184,7 +184,7 @@ ignore-on-opaque-inference=yes
 # List of class names for which member attributes should not be checked (useful
 # for classes with dynamically set attributes). This supports the use of
 # qualified names.
-ignored-classes=optparse.Values,thread._local,_thread._local,contextlib.closing,gi.repository.GLib.GError
+ignored-classes=optparse.Values,thread._local,_thread._local,contextlib.closing,gi.repository.GLib.GError,pathlib.PurePath
 
 # List of module names for which member attributes should not be checked
 # (useful for modules/projects where namespaces are manipulated during runtime
diff --git a/buildstream/_exceptions.py b/buildstream/_exceptions.py
index e55d942fd..5187357c5 100644
--- a/buildstream/_exceptions.py
+++ b/buildstream/_exceptions.py
@@ -1,5 +1,5 @@
 #
-#  Copyright (C) 2016 Codethink Limited
+#  Copyright (C) 2018 Codethink Limited
 #
 #  This program is free software; you can redistribute it and/or
 #  modify it under the terms of the GNU Lesser General Public
@@ -16,6 +16,7 @@
 #
 #  Authors:
 #        Tristan Van Berkom <tristan.vanberkom@codethink.co.uk>
+#        Tiago Gomes <tiago.gomes@codethink.co.uk>
 
 from enum import Enum
 
@@ -206,6 +207,13 @@ class LoadErrorReason(Enum):
     # Try to load a directory not a yaml file
     LOADING_DIRECTORY = 18
 
+    # A project path leads outside of the project directory
+    PROJ_PATH_INVALID = 19
+
+    # A project path points to a file of the not right kind (e.g. a
+    # socket)
+    PROJ_PATH_INVALID_KIND = 20
+
 
 # LoadError
 #
diff --git a/buildstream/_project.py b/buildstream/_project.py
index 1c30fb9bb..3ac562836 100644
--- a/buildstream/_project.py
+++ b/buildstream/_project.py
@@ -16,6 +16,7 @@
 #
 #  Authors:
 #        Tristan Van Berkom <tristan.vanberkom@codethink.co.uk>
+#        Tiago Gomes <tiago.gomes@codethink.co.uk>
 
 import os
 import multiprocessing  # for cpu_count()
@@ -291,7 +292,8 @@ class Project():
 
         self.element_path = os.path.join(
             self.directory,
-            _yaml.node_get(config, str, 'element-path')
+            _yaml.node_get_project_path(config, 'element-path', self.directory,
+                                        check_is_dir=True)
         )
 
         # Load project options
@@ -500,8 +502,11 @@ class Project():
                 if group in origin_dict:
                     del origin_dict[group]
             if origin_dict['origin'] == 'local':
+                path = _yaml.node_get_project_path(origin, 'path',
+                                                   self.directory,
+                                                   check_is_dir=True)
                 # paths are passed in relative to the project, but must be absolute
-                origin_dict['path'] = os.path.join(self.directory, origin_dict['path'])
+                origin_dict['path'] = os.path.join(self.directory, path)
             destination.append(origin_dict)
 
     # _ensure_project_dir()
diff --git a/buildstream/_yaml.py b/buildstream/_yaml.py
index 0e090e2e7..33ee444aa 100644
--- a/buildstream/_yaml.py
+++ b/buildstream/_yaml.py
@@ -1,5 +1,5 @@
 #
-#  Copyright (C) 2016 Codethink Limited
+#  Copyright (C) 2018 Codethink Limited
 #
 #  This program is free software; you can redistribute it and/or
 #  modify it under the terms of the GNU Lesser General Public
@@ -22,6 +22,7 @@ import collections
 import string
 from copy import deepcopy
 from contextlib import ExitStack
+from pathlib import Path
 
 from ruamel import yaml
 from ruamel.yaml.representer import SafeRepresenter, RoundTripRepresenter
@@ -392,6 +393,95 @@ def node_get(node, expected_type, key, indices=None, default_value=_get_sentinel
     return value
 
 
+# node_get_project_path()
+#
+# Fetches a project path from a dictionary node and validates it
+#
+# Paths are asserted to never lead to a directory outside of the project
+# directory. In addition, paths can not point to symbolic links, fifos,
+# sockets and block/character devices.
+#
+# The `check_is_file` and `check_is_dir` parameters can be used to
+# perform additional validations on the path. Note that an exception
+# will always be raised if both parameters are set to ``True``.
+#
+# Args:
+#    node (dict): A dictionary loaded from YAML
+#    key (str): The key whose value contains a path to validate
+#    project_dir (str): The project directory
+#    check_is_file (bool): If ``True`` an error will also be raised
+#                          if path does not point to a regular file.
+#                          Defaults to ``False``
+#    check_is_dir (bool): If ``True`` an error will be also raised
+#                         if path does not point to a directory.
+#                         Defaults to ``False``
+# Returns:
+#    (str): The project path
+#
+# Raises:
+#    (LoadError): In case that the project path is not valid or does not
+#                 exist
+#
+def node_get_project_path(node, key, project_dir, *,
+                          check_is_file=False, check_is_dir=False):
+    path_str = node_get(node, str, key)
+    path = Path(path_str)
+    project_dir_path = Path(project_dir)
+
+    provenance = node_get_provenance(node, key=key)
+
+    if (project_dir_path / path).is_symlink():
+        raise LoadError(LoadErrorReason.PROJ_PATH_INVALID_KIND,
+                        "{}: Specified path '{}' must not point to "
+                        "symbolic links "
+                        .format(provenance, path_str))
+
+    if path.parts and path.parts[0] == '..':
+        raise LoadError(LoadErrorReason.PROJ_PATH_INVALID,
+                        "{}: Specified path '{}' first component must "
+                        "not be '..'"
+                        .format(provenance, path_str))
+
+    try:
+        if sys.version_info[0] == 3 and sys.version_info[1] < 6:
+            full_resolved_path = (project_dir_path / path).resolve()
+        else:
+            full_resolved_path = (project_dir_path / path).resolve(strict=True)
+    except FileNotFoundError:
+        raise LoadError(LoadErrorReason.MISSING_FILE,
+                        "{}: Specified path '{}' does not exist"
+                        .format(provenance, path_str))
+
+    is_inside = project_dir_path in full_resolved_path.parents or (
+        full_resolved_path == project_dir_path)
+
+    if path.is_absolute() or not is_inside:
+        raise LoadError(LoadErrorReason.PROJ_PATH_INVALID,
+                        "{}: Specified path '{}' must not lead outside of the "
+                        "project directory"
+                        .format(provenance, path_str))
+
+    if full_resolved_path.is_socket() or (
+            full_resolved_path.is_fifo() or
+            full_resolved_path.is_block_device()):
+        raise LoadError(LoadErrorReason.PROJ_PATH_INVALID_KIND,
+                        "{}: Specified path '{}' points to an unsupported "
+                        "file kind"
+                        .format(provenance, path_str))
+
+    if check_is_file and not full_resolved_path.is_file():
+        raise LoadError(LoadErrorReason.PROJ_PATH_INVALID_KIND,
+                        "{}: Specified path '{}' is not a regular file"
+                        .format(provenance, path_str))
+
+    if check_is_dir and not full_resolved_path.is_dir():
+        raise LoadError(LoadErrorReason.PROJ_PATH_INVALID_KIND,
+                        "{}: Specified path '{}' is not a directory"
+                        .format(provenance, path_str))
+
+    return path_str
+
+
 # node_items()
 #
 # A convenience generator for iterating over loaded key/value
diff --git a/buildstream/plugin.py b/buildstream/plugin.py
index 155a9500e..836b60834 100644
--- a/buildstream/plugin.py
+++ b/buildstream/plugin.py
@@ -1,5 +1,5 @@
 #
-#  Copyright (C) 2017 Codethink Limited
+#  Copyright (C) 2018 Codethink Limited
 #
 #  This program is free software; you can redistribute it and/or
 #  modify it under the terms of the GNU Lesser General Public
@@ -335,6 +335,51 @@ class Plugin():
         """
         return _yaml.node_get(node, expected_type, member_name, default_value=default)
 
+    def node_get_project_path(self, node, key, *,
+                              check_is_file=False, check_is_dir=False):
+        """Fetches a project path from a dictionary node and validates it
+
+        Paths are asserted to never lead to a directory outside of the
+        project directory. In addition, paths can not point to symbolic
+        links, fifos, sockets and block/character devices.
+
+        The `check_is_file` and `check_is_dir` parameters can be used to
+        perform additional validations on the path. Note that an
+        exception will always be raised if both parameters are set to
+        ``True``.
+
+        Args:
+           node (dict): A dictionary loaded from YAML
+           key (str): The key whose value contains a path to validate
+           check_is_file (bool): If ``True`` an error will also be raised
+                                 if path does not point to a regular file.
+                                 Defaults to ``False``
+           check_is_dir (bool): If ``True`` an error will also be raised
+                                if path does not point to a directory.
+                                Defaults to ``False``
+
+        Returns:
+           (str): The project path
+
+        Raises:
+           :class:`.LoadError`: In the case that the project path is not
+                                valid or does not exist
+
+        *Since: 1.2*
+
+        **Example:**
+
+        .. code:: python
+
+          path = self.node_get_project_path(node, 'path')
+
+        """
+
+        return _yaml.node_get_project_path(node, key,
+                                           self.__project.directory,
+                                           check_is_file=check_is_file,
+                                           check_is_dir=check_is_dir)
+
     def node_validate(self, node, valid_keys):
         """This should be used in :func:`~buildstream.plugin.Plugin.configure`
         implementations to assert that users have only entered
diff --git a/buildstream/plugins/sources/local.py b/buildstream/plugins/sources/local.py
index e3b019f1a..058553424 100644
--- a/buildstream/plugins/sources/local.py
+++ b/buildstream/plugins/sources/local.py
@@ -1,5 +1,5 @@
 #
-#  Copyright (C) 2016 Codethink Limited
+#  Copyright (C) 2018 Codethink Limited
 #
 #  This program is free software; you can redistribute it and/or
 #  modify it under the terms of the GNU Lesser General Public
@@ -16,6 +16,7 @@
 #
 #  Authors:
 #        Tristan Van Berkom <tristan.vanberkom@codethink.co.uk>
+#        Tiago Gomes <tiago.gomes@codethink.co.uk>
 
 """
 local - stage local files and directories
@@ -36,7 +37,7 @@ local - stage local files and directories
 """
 
 import os
-from buildstream import Source, SourceError, Consistency
+from buildstream import Source, Consistency
 from buildstream import utils
 
 
@@ -51,14 +52,11 @@ class LocalSource(Source):
 
     def configure(self, node):
         self.node_validate(node, ['path'] + Source.COMMON_CONFIG_KEYS)
-
-        self.path = self.node_get_member(node, str, 'path')
+        self.path = self.node_get_project_path(node, 'path')
         self.fullpath = os.path.join(self.get_project_directory(), self.path)
 
     def preflight(self):
-        # Check if the configured file or directory really exists
-        if not os.path.exists(self.fullpath):
-            raise SourceError("Specified path '{}' does not exist".format(self.path))
+        pass
 
     def get_unique_key(self):
         if self.__unique_key is None:
diff --git a/buildstream/plugins/sources/ostree.py b/buildstream/plugins/sources/ostree.py
index 94fe5093f..3a841c488 100644
--- a/buildstream/plugins/sources/ostree.py
+++ b/buildstream/plugins/sources/ostree.py
@@ -1,5 +1,5 @@
 #
-#  Copyright (C) 2016 Codethink Limited
+#  Copyright (C) 2018 Codethink Limited
 #
 #  This program is free software; you can redistribute it and/or
 #  modify it under the terms of the GNU Lesser General Public
@@ -16,6 +16,7 @@
 #
 #  Authors:
 #        Andrew Leeming <andrew.leeming@codethink.co.uk>
+#        Tiago Gomes <tiago.gomes@codethink.co.uk>
 
 """
 ostree - stage files from an OSTree repository
@@ -73,9 +74,10 @@ class OSTreeSource(Source):
                                    utils.url_directory_name(self.url))
 
         # (optional) Not all repos are signed. But if they are, get the gpg key
-        self.gpg_key = self.node_get_member(node, str, 'gpg-key', None)
         self.gpg_key_path = None
-        if self.gpg_key is not None:
+        if self.node_get_member(node, str, 'gpg-key', None):
+            self.gpg_key = self.node_get_project_path(node, 'gpg-key',
+                                                      check_is_file=True)
             self.gpg_key_path = os.path.join(self.get_project_directory(), self.gpg_key)
 
         # Our OSTree repo handle
diff --git a/buildstream/plugins/sources/patch.py b/buildstream/plugins/sources/patch.py
index 11b66b3ea..2fa002080 100644
--- a/buildstream/plugins/sources/patch.py
+++ b/buildstream/plugins/sources/patch.py
@@ -1,5 +1,6 @@
 #
 #  Copyright Bloomberg Finance LP
+#  Copyright (C) 2018 Codethink Limited
 #
 #  This program is free software; you can redistribute it and/or
 #  modify it under the terms of the GNU Lesser General Public
@@ -16,6 +17,7 @@
 #
 #  Authors:
 #        Chandan Singh <csingh43@bloomberg.net>
+#        Tiago Gomes <tiago.gomes@codethink.co.uk>
 
 """
 patch - apply locally stored patches
@@ -52,19 +54,12 @@ class PatchSource(Source):
     # pylint: disable=attribute-defined-outside-init
 
     def configure(self, node):
-        self.path = self.node_get_member(node, str, "path")
+        self.path = self.node_get_project_path(node, 'path',
+                                               check_is_file=True)
         self.strip_level = self.node_get_member(node, int, "strip-level", 1)
         self.fullpath = os.path.join(self.get_project_directory(), self.path)
 
     def preflight(self):
-        # Check if the configured file really exists
-        if not os.path.exists(self.fullpath):
-            raise SourceError("Specified path '{}' does not exist".format(self.path),
-                              reason="patch-no-exist")
-        elif not os.path.isfile(self.fullpath):
-            raise SourceError("Specified path '{}' must be a file".format(self.path),
-                              reason="patch-not-a-file")
-
         # Check if patch is installed, get the binary at the same time
         self.host_patch = utils.get_host_tool("patch")
 
diff --git a/doc/examples/junctions/autotools/elements/base.bst b/doc/examples/junctions/autotools/elements/base.bst
new file mode 100644
index 000000000..1b85a9e8c
--- /dev/null
+++ b/doc/examples/junctions/autotools/elements/base.bst
@@ -0,0 +1,5 @@
+kind: stack
+description: Base stack
+
+depends:
+- base/alpine.bst
diff --git a/doc/examples/junctions/autotools/elements/base/alpine.bst b/doc/examples/junctions/autotools/elements/base/alpine.bst
new file mode 100644
index 000000000..cf85df5bf
--- /dev/null
+++ b/doc/examples/junctions/autotools/elements/base/alpine.bst
@@ -0,0 +1,13 @@
+kind: import
+description: |
+
+    Alpine Linux base runtime
+
+sources:
+- kind: tar
+
+  # This is a post doctored, trimmed down system image
+  # of the Alpine linux distribution.
+  #
+  url: alpine:integration-tests-base.v1.x86_64.tar.xz
+  ref: 3eb559250ba82b64a68d86d0636a6b127aa5f6d25d3601a79f79214dc9703639
diff --git a/doc/examples/junctions/autotools/elements/hello.bst b/doc/examples/junctions/autotools/elements/hello.bst
new file mode 100644
index 000000000..510f5b975
--- /dev/null
+++ b/doc/examples/junctions/autotools/elements/hello.bst
@@ -0,0 +1,21 @@
+kind: autotools
+description: |
+
+    Hello world example from automake
+
+variables:
+
+  # The hello world example lives in the doc/amhello folder.
+  #
+  # Set the %{command-subdir} variable to that location
+  # and just have the autotools element run it's commands there.
+  #
+  command-subdir: doc/amhello
+
+sources:
+- kind: tar
+  url: gnu:automake-1.16.tar.gz
+  ref: 80da43bb5665596ee389e6d8b64b4f122ea4b92a685b1dbd813cd1f0e0c2d83f
+
+depends:
+- base.bst
diff --git a/doc/examples/junctions/autotools/project.conf b/doc/examples/junctions/autotools/project.conf
new file mode 100644
index 000000000..7ee58b589
--- /dev/null
+++ b/doc/examples/junctions/autotools/project.conf
@@ -0,0 +1,13 @@
+# Unique project name
+name: autotools
+
+# Required BuildStream format version
+format-version: 9
+
+# Subdirectory where elements are stored
+element-path: elements
+
+# Define some aliases for the tarballs we download
+aliases:
+  alpine: https://gnome7.codethink.co.uk/tarballs/
+  gnu: https://ftp.gnu.org/gnu/automake/
diff --git a/doc/examples/junctions/elements/hello-junction.bst b/doc/examples/junctions/elements/hello-junction.bst
index dda865ecf..6d01e36a1 100644
--- a/doc/examples/junctions/elements/hello-junction.bst
+++ b/doc/examples/junctions/elements/hello-junction.bst
@@ -1,8 +1,4 @@
 kind: junction
-
-# Specify the source of the BuildStream project
-# We are going to use the autotools examples distributed with BuildStream in the
-# doc/examples/autotools directory
 sources:
 - kind: local
-  path: ../autotools
+  path: autotools
diff --git a/doc/source/advanced-features/junction-elements.rst b/doc/source/advanced-features/junction-elements.rst
index 929ac1217..81fc01a05 100644
--- a/doc/source/advanced-features/junction-elements.rst
+++ b/doc/source/advanced-features/junction-elements.rst
@@ -21,8 +21,8 @@ Below is a simple example of bst file for a junction element:
 .. literalinclude:: ../../examples/junctions/elements/hello-junction.bst
     :language: yaml
 
-This element imports the autotools example project found in the BuildStream
-doc/examples/autotools subdirectory.
+This element imports the autotools example subproject found in the
+BuildStream doc/examples/junctions/autotools subdirectory.
 
 .. note::
 
diff --git a/tests/artifactcache/expiry.py b/tests/artifactcache/expiry.py
index 4c741054b..9c74eb1c4 100644
--- a/tests/artifactcache/expiry.py
+++ b/tests/artifactcache/expiry.py
@@ -5,7 +5,7 @@ import pytest
 from buildstream import _yaml
 from buildstream._exceptions import ErrorDomain, LoadErrorReason
 
-from tests.testutils import cli
+from tests.testutils import cli, create_element_size
 
 
 DATA_DIR = os.path.join(
@@ -14,32 +14,12 @@ DATA_DIR = os.path.join(
 )
 
 
-def create_element(name, path, dependencies, size):
-    os.makedirs(path, exist_ok=True)
-
-    # Create a file to be included in this element's artifact
-    with open(os.path.join(path, name + '_data'), 'wb+') as f:
-        f.write(os.urandom(size))
-
-    element = {
-        'kind': 'import',
-        'sources': [
-            {
-                'kind': 'local',
-                'path': os.path.join(path, name + '_data')
-            }
-        ],
-        'depends': dependencies
-    }
-    _yaml.dump(element, os.path.join(path, name))
-
-
 # Ensure that the cache successfully removes an old artifact if we do
 # not have enough space left.
 @pytest.mark.datafiles(DATA_DIR)
 def test_artifact_expires(cli, datafiles, tmpdir):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    element_path = os.path.join(project, 'elements')
+    element_path = 'elements'
     cache_location = os.path.join(project, 'cache', 'artifacts', 'ostree')
     checkout = os.path.join(project, 'checkout')
 
@@ -52,7 +32,7 @@ def test_artifact_expires(cli, datafiles, tmpdir):
     # Create an element that uses almost the entire cache (an empty
     # ostree cache starts at about ~10KiB, so we need a bit of a
     # buffer)
-    create_element('target.bst', element_path, [], 6000000)
+    create_element_size('target.bst', project, element_path, [], 6000000)
     res = cli.run(project=project, args=['build', 'target.bst'])
     res.assert_success()
 
@@ -61,7 +41,7 @@ def test_artifact_expires(cli, datafiles, tmpdir):
     # Our cache should now be almost full. Let's create another
     # artifact and see if we can cause buildstream to delete the old
     # one.
-    create_element('target2.bst', element_path, [], 6000000)
+    create_element_size('target2.bst', project, element_path, [], 6000000)
     res = cli.run(project=project, args=['build', 'target2.bst'])
     res.assert_success()
 
@@ -82,7 +62,7 @@ def test_artifact_expires(cli, datafiles, tmpdir):
 @pytest.mark.datafiles(DATA_DIR)
 def test_artifact_too_large(cli, datafiles, tmpdir, size):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    element_path = os.path.join(project, 'elements')
+    element_path = 'elements'
 
     cli.configure({
         'cache': {
@@ -91,7 +71,7 @@ def test_artifact_too_large(cli, datafiles, tmpdir, size):
     })
 
     # Create an element whose artifact is too large
-    create_element('target.bst', element_path, [], size)
+    create_element_size('target.bst', project, element_path, [], size)
     res = cli.run(project=project, args=['build', 'target.bst'])
     res.assert_main_error(ErrorDomain.STREAM, None)
 
@@ -99,7 +79,7 @@ def test_artifact_too_large(cli, datafiles, tmpdir, size):
 @pytest.mark.datafiles(DATA_DIR)
 def test_expiry_order(cli, datafiles, tmpdir):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    element_path = os.path.join(project, 'elements')
+    element_path = 'elements'
     cache_location = os.path.join(project, 'cache', 'artifacts', 'ostree')
     checkout = os.path.join(project, 'workspace')
 
@@ -110,21 +90,21 @@ def test_expiry_order(cli, datafiles, tmpdir):
     })
 
     # Create an artifact
-    create_element('dep.bst', element_path, [], 2000000)
+    create_element_size('dep.bst', project, element_path, [], 2000000)
     res = cli.run(project=project, args=['build', 'dep.bst'])
     res.assert_success()
 
     # Create another artifact
-    create_element('unrelated.bst', element_path, [], 2000000)
+    create_element_size('unrelated.bst', project, element_path, [], 2000000)
     res = cli.run(project=project, args=['build', 'unrelated.bst'])
     res.assert_success()
 
     # And build something else
-    create_element('target.bst', element_path, [], 2000000)
+    create_element_size('target.bst', project, element_path, [], 2000000)
     res = cli.run(project=project, args=['build', 'target.bst'])
     res.assert_success()
 
-    create_element('target2.bst', element_path, [], 2000000)
+    create_element_size('target2.bst', project, element_path, [], 2000000)
     res = cli.run(project=project, args=['build', 'target2.bst'])
     res.assert_success()
 
@@ -133,7 +113,7 @@ def test_expiry_order(cli, datafiles, tmpdir):
     res.assert_success()
 
     # Finally, build something that will cause the cache to overflow
-    create_element('expire.bst', element_path, [], 2000000)
+    create_element_size('expire.bst', project, element_path, [], 2000000)
     res = cli.run(project=project, args=['build', 'expire.bst'])
     res.assert_success()
 
@@ -153,7 +133,7 @@ def test_expiry_order(cli, datafiles, tmpdir):
 @pytest.mark.datafiles(DATA_DIR)
 def test_keep_dependencies(cli, datafiles, tmpdir):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    element_path = os.path.join(project, 'elements')
+    element_path = 'elements'
     cache_location = os.path.join(project, 'cache', 'artifacts', 'ostree')
 
     cli.configure({
@@ -163,12 +143,12 @@ def test_keep_dependencies(cli, datafiles, tmpdir):
     })
 
     # Create a pretty big dependency
-    create_element('dependency.bst', element_path, [], 5000000)
+    create_element_size('dependency.bst', project, element_path, [], 5000000)
     res = cli.run(project=project, args=['build', 'dependency.bst'])
     res.assert_success()
 
     # Now create some other unrelated artifact
-    create_element('unrelated.bst', element_path, [], 4000000)
+    create_element_size('unrelated.bst', project, element_path, [], 4000000)
     res = cli.run(project=project, args=['build', 'unrelated.bst'])
     res.assert_success()
 
@@ -184,7 +164,8 @@ def test_keep_dependencies(cli, datafiles, tmpdir):
     # duplicating artifacts (bad!) we need to make this equal in size
     # or smaller than half the size of its dependencies.
     #
-    create_element('target.bst', element_path, ['dependency.bst'], 2000000)
+    create_element_size('target.bst', project,
+                        element_path, ['dependency.bst'], 2000000)
     res = cli.run(project=project, args=['build', 'target.bst'])
     res.assert_success()
 
@@ -197,7 +178,7 @@ def test_keep_dependencies(cli, datafiles, tmpdir):
 @pytest.mark.datafiles(DATA_DIR)
 def test_never_delete_dependencies(cli, datafiles, tmpdir):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    element_path = os.path.join(project, 'elements')
+    element_path = 'elements'
 
     cli.configure({
         'cache': {
@@ -206,10 +187,14 @@ def test_never_delete_dependencies(cli, datafiles, tmpdir):
     })
 
     # Create a build tree
-    create_element('dependency.bst', element_path, [], 8000000)
-    create_element('related.bst', element_path, ['dependency.bst'], 8000000)
-    create_element('target.bst', element_path, ['related.bst'], 8000000)
-    create_element('target2.bst', element_path, ['target.bst'], 8000000)
+    create_element_size('dependency.bst', project,
+                        element_path, [], 8000000)
+    create_element_size('related.bst', project,
+                        element_path, ['dependency.bst'], 8000000)
+    create_element_size('target.bst', project,
+                        element_path, ['related.bst'], 8000000)
+    create_element_size('target2.bst', project,
+                        element_path, ['target.bst'], 8000000)
 
     # We try to build this pipeline, but it's too big for the
     # cache. Since all elements are required, the build should fail.
@@ -249,7 +234,7 @@ def test_never_delete_dependencies(cli, datafiles, tmpdir):
 @pytest.mark.datafiles(DATA_DIR)
 def test_invalid_cache_quota(cli, datafiles, tmpdir, quota, success):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    element_path = os.path.join(project, 'elements')
+    os.makedirs(os.path.join(project, 'elements'))
 
     cli.configure({
         'cache': {
diff --git a/tests/examples/junctions.py b/tests/examples/junctions.py
index 49e2ebbff..d2a653884 100644
--- a/tests/examples/junctions.py
+++ b/tests/examples/junctions.py
@@ -11,42 +11,12 @@ DATA_DIR = os.path.join(
     os.path.dirname(os.path.realpath(__file__)), '..', '..', 'doc', 'examples', 'junctions'
 )
 
-JUNCTION_IMPORT_PATH = os.path.join(
-    os.path.dirname(os.path.realpath(__file__)), '..', '..', 'doc', 'examples', 'autotools'
-)
-
-
-def ammend_juntion_path_paths(tmpdir):
-    # The junction element in the examples/junctions project uses a local source type.
-    # It's "path:" must specify a relative path from the project's root directory.
-    # For the hello-junction element to function during these tests, the copy of the junctions
-    # project made in the buildstream/tmp/directory, "path:" must be ammended to be the relative
-    # path to the autotools example from the temporary test directory.
-    junction_element = os.path.join(tmpdir, "elements", "hello-junction.bst")
-    junction_element_bst = ""
-    junction_relative_path = os.path.relpath(JUNCTION_IMPORT_PATH, tmpdir)
-    with open(junction_element, 'r') as f:
-        junction_element_bst = f.read()
-    ammended_element_bst = junction_element_bst.replace("../autotools", junction_relative_path)
-    with open(junction_element, 'w') as f:
-        f.write(ammended_element_bst)
-
-
-# Check that the autotools project is where the junctions example expects and
-# contains the hello.bst element.
-@pytest.mark.datafiles(DATA_DIR)
-def test_autotools_example_is_present(datafiles):
-    autotools_path = JUNCTION_IMPORT_PATH
-    assert os.path.exists(autotools_path)
-    assert os.path.exists(os.path.join(autotools_path, "elements", "hello.bst"))
-
 
 # Test that the project builds successfully
 @pytest.mark.skipif(not IS_LINUX, reason='Only available on linux')
 @pytest.mark.datafiles(DATA_DIR)
 def test_build(cli, tmpdir, datafiles):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    ammend_juntion_path_paths(str(tmpdir))
 
     result = cli.run(project=project, args=['build', 'callHello.bst'])
     result.assert_success()
@@ -57,7 +27,6 @@ def test_build(cli, tmpdir, datafiles):
 @pytest.mark.datafiles(DATA_DIR)
 def test_shell_call_hello(cli, tmpdir, datafiles):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    ammend_juntion_path_paths(str(tmpdir))
 
     result = cli.run(project=project, args=['build', 'callHello.bst'])
     result.assert_success()
@@ -73,7 +42,6 @@ def test_shell_call_hello(cli, tmpdir, datafiles):
 def test_open_cross_junction_workspace(cli, tmpdir, datafiles):
     project = os.path.join(datafiles.dirname, datafiles.basename)
     workspace_dir = os.path.join(str(tmpdir), "workspace_hello_junction")
-    ammend_juntion_path_paths(str(tmpdir))
 
     result = cli.run(project=project,
                      args=['workspace', 'open', 'hello-junction.bst:hello.bst', workspace_dir])
diff --git a/tests/format/project.py b/tests/format/project.py
index 9d595981b..df1a2364b 100644
--- a/tests/format/project.py
+++ b/tests/format/project.py
@@ -2,7 +2,7 @@ import os
 import pytest
 from buildstream import _yaml
 from buildstream._exceptions import ErrorDomain, LoadErrorReason
-from tests.testutils.runcli import cli
+from tests.testutils import cli, filetypegenerator
 
 
 # Project directory
@@ -90,6 +90,48 @@ def test_project_unsupported(cli, datafiles):
     result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.UNSUPPORTED_PROJECT)
 
 
+@pytest.mark.datafiles(os.path.join(DATA_DIR, 'element-path'))
+def test_missing_element_path_directory(cli, datafiles):
+    project = os.path.join(datafiles.dirname, datafiles.basename)
+    result = cli.run(project=project, args=['workspace', 'list'])
+    result.assert_main_error(ErrorDomain.LOAD,
+                             LoadErrorReason.MISSING_FILE)
+
+
+@pytest.mark.datafiles(os.path.join(DATA_DIR, 'element-path'))
+def test_element_path_not_a_directory(cli, datafiles):
+    project = os.path.join(datafiles.dirname, datafiles.basename)
+    path = os.path.join(project, 'elements')
+    for file_type in filetypegenerator.generate_file_types(path):
+        result = cli.run(project=project, args=['workspace', 'list'])
+        if not os.path.isdir(path):
+            result.assert_main_error(ErrorDomain.LOAD,
+                                     LoadErrorReason.PROJ_PATH_INVALID_KIND)
+        else:
+            result.assert_success()
+
+
+@pytest.mark.datafiles(os.path.join(DATA_DIR, 'local-plugin'))
+def test_missing_local_plugin_directory(cli, datafiles):
+    project = os.path.join(datafiles.dirname, datafiles.basename)
+    result = cli.run(project=project, args=['workspace', 'list'])
+    result.assert_main_error(ErrorDomain.LOAD,
+                             LoadErrorReason.MISSING_FILE)
+
+
+@pytest.mark.datafiles(os.path.join(DATA_DIR, 'local-plugin'))
+def test_local_plugin_not_directory(cli, datafiles):
+    project = os.path.join(datafiles.dirname, datafiles.basename)
+    path = os.path.join(project, 'plugins')
+    for file_type in filetypegenerator.generate_file_types(path):
+        result = cli.run(project=project, args=['workspace', 'list'])
+        if not os.path.isdir(path):
+            result.assert_main_error(ErrorDomain.LOAD,
+                                     LoadErrorReason.PROJ_PATH_INVALID_KIND)
+        else:
+            result.assert_success()
+
+
 @pytest.mark.datafiles(DATA_DIR)
 def test_project_plugin_load_allowed(cli, datafiles):
     project = os.path.join(datafiles.dirname, datafiles.basename, 'plugin-allowed')
diff --git a/tests/format/project/element-path/project.conf b/tests/format/project/element-path/project.conf
new file mode 100644
index 000000000..57e87de4f
--- /dev/null
+++ b/tests/format/project/element-path/project.conf
@@ -0,0 +1,2 @@
+name: foo
+element-path: elements
diff --git a/tests/format/project/local-plugin/project.conf b/tests/format/project/local-plugin/project.conf
new file mode 100644
index 000000000..97166e350
--- /dev/null
+++ b/tests/format/project/local-plugin/project.conf
@@ -0,0 +1,6 @@
+name: foo
+plugins:
+- origin: local
+  path: plugins
+  sources:
+    mysource: 0
diff --git a/tests/frontend/push.py b/tests/frontend/push.py
index 471991ef7..be324ca53 100644
--- a/tests/frontend/push.py
+++ b/tests/frontend/push.py
@@ -202,7 +202,7 @@ def test_push_after_pull(cli, tmpdir, datafiles):
 @pytest.mark.datafiles(DATA_DIR)
 def test_artifact_expires(cli, datafiles, tmpdir):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    element_path = os.path.join(project, 'elements')
+    element_path = 'elements'
 
     # Create an artifact share (remote artifact cache) in the tmpdir/artifactshare
     # Mock a file system with 12 MB free disk space
@@ -215,12 +215,12 @@ def test_artifact_expires(cli, datafiles, tmpdir):
         })
 
         # Create and build an element of 5 MB
-        create_element_size('element1.bst', element_path, [], int(5e6))  # [] => no deps
+        create_element_size('element1.bst', project, element_path, [], int(5e6))
         result = cli.run(project=project, args=['build', 'element1.bst'])
         result.assert_success()
 
         # Create and build an element of 5 MB
-        create_element_size('element2.bst', element_path, [], int(5e6))  # [] => no deps
+        create_element_size('element2.bst', project, element_path, [], int(5e6))
         result = cli.run(project=project, args=['build', 'element2.bst'])
         result.assert_success()
 
@@ -231,7 +231,7 @@ def test_artifact_expires(cli, datafiles, tmpdir):
         assert_shared(cli, share, project, 'element2.bst')
 
         # Create and build another element of 5 MB (This will exceed the free disk space available)
-        create_element_size('element3.bst', element_path, [], int(5e6))
+        create_element_size('element3.bst', project, element_path, [], int(5e6))
         result = cli.run(project=project, args=['build', 'element3.bst'])
         result.assert_success()
 
@@ -250,7 +250,7 @@ def test_artifact_expires(cli, datafiles, tmpdir):
 @pytest.mark.datafiles(DATA_DIR)
 def test_artifact_too_large(cli, datafiles, tmpdir):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    element_path = os.path.join(project, 'elements')
+    element_path = 'elements'
 
     # Create an artifact share (remote cache) in tmpdir/artifactshare
     # Mock a file system with 5 MB total space
@@ -263,12 +263,12 @@ def test_artifact_too_large(cli, datafiles, tmpdir):
         })
 
         # Create and push a 3MB element
-        create_element_size('small_element.bst', element_path, [], int(3e6))
+        create_element_size('small_element.bst', project, element_path, [], int(3e6))
         result = cli.run(project=project, args=['build', 'small_element.bst'])
         result.assert_success()
 
         # Create and try to push a 6MB element.
-        create_element_size('large_element.bst', element_path, [], int(6e6))
+        create_element_size('large_element.bst', project, element_path, [], int(6e6))
         result = cli.run(project=project, args=['build', 'large_element.bst'])
         result.assert_success()
 
@@ -285,7 +285,7 @@ def test_artifact_too_large(cli, datafiles, tmpdir):
 @pytest.mark.datafiles(DATA_DIR)
 def test_recently_pulled_artifact_does_not_expire(cli, datafiles, tmpdir):
     project = os.path.join(datafiles.dirname, datafiles.basename)
-    element_path = os.path.join(project, 'elements')
+    element_path = 'elements'
 
     # Create an artifact share (remote cache) in tmpdir/artifactshare
     # Mock a file system with 12 MB free disk space
@@ -298,11 +298,11 @@ def test_recently_pulled_artifact_does_not_expire(cli, datafiles, tmpdir):
         })
 
         # Create and build 2 elements, each of 5 MB.
-        create_element_size('element1.bst', element_path, [], int(5e6))
+        create_element_size('element1.bst', project, element_path, [], int(5e6))
         result = cli.run(project=project, args=['build', 'element1.bst'])
         result.assert_success()
 
-        create_element_size('element2.bst', element_path, [], int(5e6))
+        create_element_size('element2.bst', project, element_path, [], int(5e6))
         result = cli.run(project=project, args=['build', 'element2.bst'])
         result.assert_success()
 
@@ -327,7 +327,7 @@ def test_recently_pulled_artifact_does_not_expire(cli, datafiles, tmpdir):
         assert cli.get_element_state(project, 'element1.bst') == 'cached'
 
         # Create and build the element3 (of 5 MB)
-        create_element_size('element3.bst', element_path, [], int(5e6))
+        create_element_size('element3.bst', project, element_path, [], int(5e6))
         result = cli.run(project=project, args=['build', 'element3.bst'])
         result.assert_success()
 
diff --git a/tests/sources/local.py b/tests/sources/local.py
index 9dfb5f972..de12473d9 100644
--- a/tests/sources/local.py
+++ b/tests/sources/local.py
@@ -1,8 +1,8 @@
 import os
 import pytest
 
-from buildstream._exceptions import ErrorDomain
-from tests.testutils import cli
+from buildstream._exceptions import ErrorDomain, LoadErrorReason
+from tests.testutils import cli, filetypegenerator
 
 DATA_DIR = os.path.join(
     os.path.dirname(os.path.realpath(__file__)),
@@ -11,17 +11,62 @@ DATA_DIR = os.path.join(
 
 
 @pytest.mark.datafiles(os.path.join(DATA_DIR, 'basic'))
-def test_missing_file(cli, tmpdir, datafiles):
+def test_missing_path(cli, tmpdir, datafiles):
     project = os.path.join(datafiles.dirname, datafiles.basename)
 
     # Removing the local file causes preflight to fail
-    localfile = os.path.join(datafiles.dirname, datafiles.basename, 'file.txt')
+    localfile = os.path.join(project, 'file.txt')
     os.remove(localfile)
 
     result = cli.run(project=project, args=[
         'show', 'target.bst'
     ])
-    result.assert_main_error(ErrorDomain.SOURCE, None)
+    result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.MISSING_FILE)
+
+
+@pytest.mark.datafiles(os.path.join(DATA_DIR, 'basic'))
+def test_non_regular_file_or_directory(cli, tmpdir, datafiles):
+    project = os.path.join(datafiles.dirname, datafiles.basename)
+    localfile = os.path.join(project, 'file.txt')
+
+    for file_type in filetypegenerator.generate_file_types(localfile):
+        result = cli.run(project=project, args=[
+            'show', 'target.bst'
+        ])
+        if os.path.isdir(localfile) and not os.path.islink(localfile):
+            result.assert_success()
+        elif os.path.isfile(localfile) and not os.path.islink(localfile):
+            result.assert_success()
+        else:
+            result.assert_main_error(ErrorDomain.LOAD,
+                                     LoadErrorReason.PROJ_PATH_INVALID_KIND)
+
+
+@pytest.mark.datafiles(os.path.join(DATA_DIR, 'basic'))
+def test_invalid_absolute_path(cli, tmpdir, datafiles):
+    project = os.path.join(datafiles.dirname, datafiles.basename)
+
+    with open(os.path.join(project, "target.bst"), 'r') as f:
+        old_yaml = f.read()
+
+    new_yaml = old_yaml.replace("file.txt", os.path.join(project, "file.txt"))
+    assert old_yaml != new_yaml
+
+    with open(os.path.join(project, "target.bst"), 'w') as f:
+        f.write(new_yaml)
+
+    result = cli.run(project=project, args=['show', 'target.bst'])
+    result.assert_main_error(ErrorDomain.LOAD,
+                             LoadErrorReason.PROJ_PATH_INVALID)
+
+
+@pytest.mark.datafiles(os.path.join(DATA_DIR, 'invalid-relative-path'))
+def test_invalid_relative_path(cli, tmpdir, datafiles):
+    project = os.path.join(datafiles.dirname, datafiles.basename)
+
+    result = cli.run(project=project, args=['show', 'target.bst'])
+    result.assert_main_error(ErrorDomain.LOAD,
+                             LoadErrorReason.PROJ_PATH_INVALID)
 
 
 @pytest.mark.datafiles(os.path.join(DATA_DIR, 'basic'))
diff --git a/tests/sources/local/invalid-relative-path/file.txt b/tests/sources/local/invalid-relative-path/file.txt
new file mode 100644
index 000000000..a496efee8
--- /dev/null
+++ b/tests/sources/local/invalid-relative-path/file.txt
@@ -0,0 +1 @@
+This is a text file
diff --git a/tests/sources/local/invalid-relative-path/project.conf b/tests/sources/local/invalid-relative-path/project.conf
new file mode 100644
index 000000000..afa0f5475
--- /dev/null
+++ b/tests/sources/local/invalid-relative-path/project.conf
@@ -0,0 +1,2 @@
+# Basic project
+name: foo
diff --git a/tests/sources/local/invalid-relative-path/target.bst b/tests/sources/local/invalid-relative-path/target.bst
new file mode 100644
index 000000000..b09f180e8
--- /dev/null
+++ b/tests/sources/local/invalid-relative-path/target.bst
@@ -0,0 +1,5 @@
+kind: import
+description: This is the pony
+sources:
+- kind: local
+  path: ../invalid-relative-path/file.txt
diff --git a/tests/sources/patch.py b/tests/sources/patch.py
index 697a0ccfb..39d43369d 100644
--- a/tests/sources/patch.py
+++ b/tests/sources/patch.py
@@ -1,8 +1,8 @@
 import os
 import pytest
 
-from buildstream._exceptions import ErrorDomain
-from tests.testutils import cli
+from buildstream._exceptions import ErrorDomain, LoadErrorReason
+from tests.testutils import cli, filetypegenerator
 
 DATA_DIR = os.path.join(
     os.path.dirname(os.path.realpath(__file__)),
@@ -15,27 +15,56 @@ def test_missing_patch(cli, tmpdir, datafiles):
     project = os.path.join(datafiles.dirname, datafiles.basename)
 
     # Removing the local file causes preflight to fail
-    localfile = os.path.join(datafiles.dirname, datafiles.basename, 'file_1.patch')
+    localfile = os.path.join(project, 'file_1.patch')
     os.remove(localfile)
 
     result = cli.run(project=project, args=[
         'show', 'target.bst'
     ])
-    result.assert_main_error(ErrorDomain.SOURCE, 'patch-no-exist')
+    result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.MISSING_FILE)
 
 
 @pytest.mark.datafiles(os.path.join(DATA_DIR, 'basic'))
 def test_non_regular_file_patch(cli, tmpdir, datafiles):
     project = os.path.join(datafiles.dirname, datafiles.basename)
 
-    # Add a fifo, that's not a regular file, should cause explosions
-    patch_path = os.path.join(datafiles.dirname, datafiles.basename, 'irregular_file.patch')
-    os.mkfifo(patch_path)
+    patch_path = os.path.join(project, 'irregular_file.patch')
+    for file_type in filetypegenerator.generate_file_types(patch_path):
+        result = cli.run(project=project, args=[
+            'show', 'irregular.bst'
+        ])
+        if os.path.isfile(patch_path) and not os.path.islink(patch_path):
+            result.assert_success()
+        else:
+            result.assert_main_error(ErrorDomain.LOAD,
+                                     LoadErrorReason.PROJ_PATH_INVALID_KIND)
 
-    result = cli.run(project=project, args=[
-        'show', 'irregular.bst'
-    ])
-    result.assert_main_error(ErrorDomain.SOURCE, "patch-not-a-file")
+
+@pytest.mark.datafiles(os.path.join(DATA_DIR, 'basic'))
+def test_invalid_absolute_path(cli, tmpdir, datafiles):
+    project = os.path.join(datafiles.dirname, datafiles.basename)
+
+    with open(os.path.join(project, "target.bst"), 'r') as f:
+        old_yaml = f.read()
+    new_yaml = old_yaml.replace("file_1.patch",
+                                os.path.join(project, "file_1.patch"))
+    assert old_yaml != new_yaml
+
+    with open(os.path.join(project, "target.bst"), 'w') as f:
+        f.write(new_yaml)
+
+    result = cli.run(project=project, args=['show', 'target.bst'])
+    result.assert_main_error(ErrorDomain.LOAD,
+                             LoadErrorReason.PROJ_PATH_INVALID)
+
+
+@pytest.mark.datafiles(os.path.join(DATA_DIR, 'invalid-relative-path'))
+def test_invalid_relative_path(cli, tmpdir, datafiles):
+    project = os.path.join(datafiles.dirname, datafiles.basename)
+
+    result = cli.run(project=project, args=['show', 'irregular.bst'])
+    result.assert_main_error(ErrorDomain.LOAD,
+                             LoadErrorReason.PROJ_PATH_INVALID)
 
 
 @pytest.mark.datafiles(os.path.join(DATA_DIR, 'basic'))
diff --git a/tests/sources/patch/invalid-relative-path/file_1.patch b/tests/sources/patch/invalid-relative-path/file_1.patch
new file mode 100644
index 000000000..424a486dd
--- /dev/null
+++ b/tests/sources/patch/invalid-relative-path/file_1.patch
@@ -0,0 +1,7 @@
+diff --git a/file.txt b/file.txt
+index a496efe..341ef26 100644
+--- a/file.txt
++++ b/file.txt
+@@ -1 +1 @@
+-This is a text file
++This is text file with superpowers
diff --git a/tests/sources/patch/invalid-relative-path/irregular.bst b/tests/sources/patch/invalid-relative-path/irregular.bst
new file mode 100644
index 000000000..6b63a4edb
--- /dev/null
+++ b/tests/sources/patch/invalid-relative-path/irregular.bst
@@ -0,0 +1,5 @@
+kind: import
+description: This is the pony
+sources:
+- kind: patch
+  path: ../invalid-relative-path/irregular_file.patch
diff --git a/tests/sources/patch/invalid-relative-path/project.conf b/tests/sources/patch/invalid-relative-path/project.conf
new file mode 100644
index 000000000..afa0f5475
--- /dev/null
+++ b/tests/sources/patch/invalid-relative-path/project.conf
@@ -0,0 +1,2 @@
+# Basic project
+name: foo
diff --git a/tests/testutils/element_generators.py b/tests/testutils/element_generators.py
index 3f6090da8..49f235c61 100644
--- a/tests/testutils/element_generators.py
+++ b/tests/testutils/element_generators.py
@@ -18,11 +18,12 @@ from buildstream import _yaml
 # Returns:
 #  Nothing (creates a .bst file of specified size)
 #
-def create_element_size(name, path, dependencies, size):
-    os.makedirs(path, exist_ok=True)
+def create_element_size(name, project_dir, elements_path, dependencies, size):
+    full_elements_path = os.path.join(project_dir, elements_path)
+    os.makedirs(full_elements_path, exist_ok=True)
 
     # Create a file to be included in this element's artifact
-    with open(os.path.join(path, name + '_data'), 'wb+') as f:
+    with open(os.path.join(project_dir, name + '_data'), 'wb+') as f:
         f.write(os.urandom(size))
 
     # Simplest case: We want this file (of specified size) to just
@@ -32,9 +33,9 @@ def create_element_size(name, path, dependencies, size):
         'sources': [
             {
                 'kind': 'local',
-                'path': os.path.join(path, name + '_data')
+                'path': name + '_data'
             }
         ],
         'depends': dependencies
     }
-    _yaml.dump(element, os.path.join(path, name))
+    _yaml.dump(element, os.path.join(project_dir, elements_path, name))
diff --git a/tests/testutils/filetypegenerator.py b/tests/testutils/filetypegenerator.py
new file mode 100644
index 000000000..2dadb7e80
--- /dev/null
+++ b/tests/testutils/filetypegenerator.py
@@ -0,0 +1,62 @@
+#
+#  Copyright (C) 2018 Codethink Limited
+#
+#  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/>.
+#
+#  Authors:
+#        Tiago Gomes <tiago.gomes@codethink.co.uk>
+
+import os
+import socket
+
+
+# generate_file_types()
+#
+# Generator that creates a regular file directory, symbolic link, fifo
+# and socket at the specified path.
+#
+# Args:
+#  path: (str) path where to create each different type of file
+#
+def generate_file_types(path):
+    def clean():
+        if os.path.exists(path):
+            if os.path.isdir(path):
+                os.rmdir(path)
+            else:
+                os.remove(path)
+
+    clean()
+
+    with open(path, 'w') as f:
+        pass
+    yield
+    clean()
+
+    os.makedirs(path)
+    yield
+    clean()
+
+    os.symlink("project.conf", path)
+    yield
+    clean()
+
+    os.mkfifo(path)
+    yield
+    clean()
+
+    s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+    s.bind(path)
+    yield
+    clean()