Refactoring: Renamed _BstError -> BstError

Base class for exceptions is now a part of the already private _exceptions module

Also moved PipelineError from _pipeline -> _exceptions module

8 files changed, 52 insertions, 50 deletions

diff --git a/buildstream/_exceptions.py b/buildstream/_exceptions.py
index 587e8dd80..328dcca4e 100644
--- a/buildstream/_exceptions.py
+++ b/buildstream/_exceptions.py
@@ -40,12 +40,12 @@ def _get_last_exception():
 # context to exceptions raised by plugins in child tasks, this
 # context can then be communicated back to the main process.
 #
-class _BstError(Exception):
+class BstError(Exception):
 
     def __init__(self, message):
         global _last_exception
 
-        super(_BstError, self).__init__(message)
+        super(BstError, self).__init__(message)
 
         # The build sandbox in which the error occurred, if the
         # error occurred at element assembly time.
@@ -63,7 +63,7 @@ class _BstError(Exception):
 # This exception is raised either by the plugin loading process,
 # or by the base :class:`.Plugin` element itself.
 #
-class PluginError(_BstError):
+class PluginError(BstError):
     pass
 
 
@@ -116,7 +116,7 @@ class LoadErrorReason(Enum):
 # This exception is raised when loading or parsing YAML, or when
 # interpreting project YAML
 #
-class LoadError(_BstError):
+class LoadError(BstError):
     def __init__(self, reason, message):
         super(LoadError, self).__init__(message)
 
@@ -130,7 +130,7 @@ class LoadError(_BstError):
 # Raised when a :class:`.Source` or :class:`.Element` plugin fails to
 # implement a mandatory method
 #
-class ImplError(_BstError):
+class ImplError(BstError):
     pass
 
 
@@ -143,14 +143,14 @@ class ImplError(_BstError):
 # can not be found. E.g. The :class:`.Sandbox` class expects that
 # bubblewrap is installed for it to work.
 #
-class ProgramNotFoundError(_BstError):
+class ProgramNotFoundError(BstError):
     pass
 
 
 # PlatformError
 #
 # Raised if the current platform is not supported.
-class PlatformError(_BstError):
+class PlatformError(BstError):
     pass
 
 
@@ -158,7 +158,7 @@ class PlatformError(_BstError):
 #
 # Raised when errors are encountered by the sandbox implementation
 #
-class SandboxError(_BstError):
+class SandboxError(BstError):
     pass
 
 
@@ -166,5 +166,21 @@ class SandboxError(_BstError):
 #
 # Raised when errors are encountered in the artifact caches
 #
-class ArtifactError(_BstError):
+class ArtifactError(BstError):
     pass
+
+
+# PipelineError
+#
+# Raised when a pipeline fails
+#
+class PipelineError(BstError):
+
+    def __init__(self, message=None):
+
+        # The empty string should never appear to a user,
+        # this only allows us to treat this internal error as
+        # a BstError from the frontend.
+        if message is None:
+            message = ""
+        super(PipelineError, self).__init__(message)
diff --git a/buildstream/_frontend/main.py b/buildstream/_frontend/main.py
index 662f267cb..33e900d5c 100644
--- a/buildstream/_frontend/main.py
+++ b/buildstream/_frontend/main.py
@@ -28,7 +28,7 @@ from blessings import Terminal
 from .. import Context, Project, Scope, Consistency
 
 # Import various buildstream internals
-from .._exceptions import _BstError, LoadError
+from .._exceptions import BstError, LoadError
 from .._message import MessageType, unconditional_messages
 from .._pipeline import Pipeline, PipelineError
 from .._scheduler import Scheduler
@@ -313,7 +313,7 @@ def pull(app, elements, deps):
         to_pull = app.pipeline.deps_elements(deps)
         app.pipeline.pull(app.scheduler, to_pull)
         click.echo("")
-    except _BstError as e:
+    except BstError as e:
         click.echo("")
         click.echo("ERROR: {}".format(e))
         sys.exit(-1)
@@ -343,7 +343,7 @@ def push(app, elements, deps):
         to_push = app.pipeline.deps_elements(deps)
         app.pipeline.push(app.scheduler, to_push)
         click.echo("")
-    except _BstError as e:
+    except BstError as e:
         click.echo("")
         click.echo("ERROR: {}".format(e))
         sys.exit(-1)
@@ -489,7 +489,7 @@ def shell(app, element, sysroot, build, command):
     try:
         exitcode = app.pipeline.targets[0]._shell(scope, sysroot, command=command)
         sys.exit(exitcode)
-    except _BstError as e:
+    except BstError as e:
         click.echo("")
         click.echo("Errors shelling into this pipeline: %s" % str(e))
         sys.exit(-1)
@@ -514,7 +514,7 @@ def checkout(app, element, directory, force, integrate):
     try:
         app.pipeline.checkout(directory, force, integrate)
         click.echo("")
-    except _BstError as e:
+    except BstError as e:
         click.echo("")
         click.echo("ERROR: {}".format(e))
         sys.exit(-1)
@@ -548,7 +548,7 @@ def source_bundle(app, target, force, directory,
         app.pipeline.source_bundle(app.scheduler, dependencies, force, track,
                                    compression, directory)
         click.echo("")
-    except _BstError as e:
+    except BstError as e:
         click.echo("")
         click.echo("ERROR: {}".format(e))
         sys.exit(-1)
@@ -586,7 +586,7 @@ def workspace_open(app, no_checkout, force, source, track, element, directory):
     try:
         app.pipeline.open_workspace(app.scheduler, directory, source, no_checkout, track, force)
         click.echo("")
-    except _BstError as e:
+    except BstError as e:
         click.echo("")
         click.echo("ERROR: {}".format(e))
         sys.exit(-1)
@@ -615,7 +615,7 @@ def workspace_close(app, source, remove_dir, element):
     try:
         app.pipeline.close_workspace(source, remove_dir)
         click.echo("")
-    except _BstError as e:
+    except BstError as e:
         click.echo("")
         click.echo("ERROR: {}".format(e))
         sys.exit(-1)
@@ -645,7 +645,7 @@ def workspace_reset(app, source, track, no_checkout, element):
     try:
         app.pipeline.reset_workspace(app.scheduler, source, track, no_checkout)
         click.echo("")
-    except _BstError as e:
+    except BstError as e:
         click.echo("")
         click.echo("ERROR: {}".format(e))
         sys.exit(-1)
@@ -665,13 +665,13 @@ def workspace_list(app):
     try:
         context = Context(app.main_options['option'])
         context.load(config)
-    except _BstError as e:
+    except BstError as e:
         click.echo("Error loading user configuration: {}".format(e))
         sys.exit(-1)
 
     try:
         project = Project(directory, context)
-    except _BstError as e:
+    except BstError as e:
         click.echo("Error loading project: {}".format(e))
         sys.exit(-1)
 
@@ -765,7 +765,7 @@ class App():
         try:
             self.context = Context(self.main_options['option'])
             self.context.load(config)
-        except _BstError as e:
+        except BstError as e:
             click.echo("Error loading user configuration: %s" % str(e))
             sys.exit(-1)
 
@@ -823,7 +823,7 @@ class App():
 
         try:
             self.project = Project(directory, self.context)
-        except _BstError as e:
+        except BstError as e:
             click.echo("Error loading project: %s" % str(e))
             sys.exit(-1)
 
@@ -836,7 +836,7 @@ class App():
                                      resolve_ticker=self.resolve_ticker,
                                      remote_ticker=self.remote_ticker,
                                      cache_ticker=self.cache_ticker)
-        except _BstError as e:
+        except BstError as e:
             click.echo("Error loading pipeline: %s" % str(e))
             sys.exit(-1)
 
diff --git a/buildstream/_ostree.py b/buildstream/_ostree.py
index 8e390e94b..794c57df3 100644
--- a/buildstream/_ostree.py
+++ b/buildstream/_ostree.py
@@ -26,7 +26,7 @@ import os
 import subprocess
 from . import _site
 from . import utils
-from ._exceptions import _BstError
+from ._exceptions import BstError
 
 import gi
 gi.require_version('OSTree', '1.0')
@@ -35,7 +35,7 @@ from gi.repository.GLib import Variant, VariantDict  # nopep8
 
 
 # For users of this file, they must expect (except) it.
-class OSTreeError(_BstError):
+class OSTreeError(BstError):
     pass
 
 
diff --git a/buildstream/_pipeline.py b/buildstream/_pipeline.py
index c7cd61ecf..90ed899ea 100644
--- a/buildstream/_pipeline.py
+++ b/buildstream/_pipeline.py
@@ -29,7 +29,7 @@ from operator import itemgetter
 from tempfile import TemporaryDirectory
 from pluginbase import PluginBase
 
-from ._exceptions import _BstError, ArtifactError, ImplError, LoadError
+from ._exceptions import PipelineError, ArtifactError, ImplError
 from ._message import Message, MessageType
 from ._elementfactory import ElementFactory
 from ._loader import Loader
@@ -44,20 +44,6 @@ from .element import Element
 from ._scheduler import SchedStatus, TrackQueue, FetchQueue, BuildQueue, PullQueue, PushQueue
 
 
-# Internal exception raised when a pipeline fails
-#
-class PipelineError(_BstError):
-
-    def __init__(self, message=None):
-
-        # The empty string should never appear to a user,
-        # this only allows us to treat this internal error as
-        # a _BstError from the frontend.
-        if message is None:
-            message = ""
-        super(PipelineError, self).__init__(message)
-
-
 class Planner():
     def __init__(self):
         self.depth_map = {}
diff --git a/buildstream/_scheduler/job.py b/buildstream/_scheduler/job.py
index d8e720d9f..43b6b7c78 100644
--- a/buildstream/_scheduler/job.py
+++ b/buildstream/_scheduler/job.py
@@ -30,7 +30,7 @@ import multiprocessing
 from ruamel import yaml
 
 # BuildStream toplevel imports
-from .._exceptions import _BstError
+from .._exceptions import BstError
 from .._message import Message, MessageType, unconditional_messages
 from ..plugin import _plugin_lookup
 from .. import _yaml, _signals, utils
@@ -267,7 +267,7 @@ class Job():
                     envelope = Envelope('result', result)
                     self.queue.put(envelope)
 
-            except _BstError as e:
+            except BstError as e:
                 elapsed = datetime.datetime.now() - starttime
 
                 if self.tries <= self.max_retries:
@@ -281,7 +281,7 @@ class Job():
                 self.child_shutdown(1)
 
             except Exception as e:
-                # If an unhandled (not normalized to _BstError) occurs, that's a bug,
+                # If an unhandled (not normalized to BstError) occurs, that's a bug,
                 # send the traceback and formatted exception back to the frontend
                 # and print it to the log file.
                 #
diff --git a/buildstream/element.py b/buildstream/element.py
index ac5d69ac6..6c55026ee 100644
--- a/buildstream/element.py
+++ b/buildstream/element.py
@@ -37,7 +37,7 @@ import shutil
 
 from . import _yaml
 from ._variables import Variables
-from ._exceptions import _BstError, LoadError, LoadErrorReason, ImplError
+from ._exceptions import BstError, LoadError, LoadErrorReason, ImplError
 from . import Plugin, Consistency
 from .project import BST_ARTIFACT_VERSION as BST_CORE_ARTIFACT_VERSION
 from . import SandboxFlags
@@ -81,7 +81,7 @@ class Scope(Enum):
     """
 
 
-class ElementError(_BstError):
+class ElementError(BstError):
     """Raised by Element implementations.
 
     This exception is raised when an :class:`.Element` encounters an error.
@@ -1066,7 +1066,7 @@ class Element(Plugin):
                     self.stage(sandbox)
                     # Step 3 - Assemble
                     collect = self.assemble(sandbox)
-                except _BstError as e:
+                except BstError as e:
                     # If an error occurred assembling an element in a sandbox,
                     # then tack on the sandbox directory to the error
                     e.sandbox = rootdir
diff --git a/buildstream/plugin.py b/buildstream/plugin.py
index 23d34ab10..abbed7dca 100644
--- a/buildstream/plugin.py
+++ b/buildstream/plugin.py
@@ -77,7 +77,7 @@ from weakref import WeakValueDictionary
 
 from . import _yaml, _signals
 from . import utils
-from ._exceptions import PluginError, ImplError, _BstError
+from ._exceptions import PluginError, ImplError, BstError
 from ._message import Message, MessageType
 
 
@@ -475,7 +475,7 @@ class Plugin():
                 self.__context._push_message_depth(silent_nested)
                 yield
 
-            except _BstError as e:
+            except BstError as e:
                 # Note the failure in status messages and reraise, the scheduler
                 # expects an error when there is an error.
                 elapsed = datetime.datetime.now() - starttime
diff --git a/buildstream/source.py b/buildstream/source.py
index aeae41220..629d41a6b 100644
--- a/buildstream/source.py
+++ b/buildstream/source.py
@@ -28,7 +28,7 @@ import shutil
 from contextlib import contextmanager
 
 from . import _yaml, _signals, utils
-from ._exceptions import _BstError, ImplError, LoadError, LoadErrorReason
+from ._exceptions import BstError, ImplError, LoadError, LoadErrorReason
 from . import Plugin
 
 
@@ -55,7 +55,7 @@ class Consistency():
     """
 
 
-class SourceError(_BstError):
+class SourceError(BstError):
     """Raised by Source implementations.
 
     This exception is raised when a :class:`.Source` encounters an error.