Merging release/0.4.0 into master. RE:#BITBUCKET-11

Branch: master

HISTORY.rst

@@ -1,5 +1,14 @@
 .. :changelog:
 
+.. Unreleased Changes
+
+0.4.0 (2018-04-18)
+------------------
+* Auto-versioning now happens via ``setuptools_scm``, replacing previous calls to ``natcap.versioner``.
+* Added an option to `TaskGraph` constructor to allow negative values in the `n_workers` argument to indicate that the entire object should run in the main thread. A value of 0 will indicate that no multiprocessing will be used but concurrency will be allowed for non-blocking `add_task`.
+* Added an abstract class `task.EncapsulatedTaskOp` that can be used to instance a class that needs scope in order to be used as an operation passed to a process. The advantage of using `EncapsulatedTaskOp` is that the `__name__` hash used by `TaskGraph` to determine if a task is unique is calculated in the superclass and the subclass need only worry about implementation of `__call__`.
+* Added a `priority` optional scalar argument to `TaskGraph.add_task` to indicates the priority preference of the task to be executed. A higher priority task whose dependencies are satisfied will executed before one with a lower priority.
+
 0.3.0 (2017-11-17)
 ------------------
 * Refactor of core scheduler. Old scheduler used asynchronicity to attempt to test if a Task was complete, occasionally testing all Tasks in potential work queue per task completion. Scheduler now uses bookkeeping to keep track of all dependencies and submits tasks for work only when all dependencies are satisfied.

setup.py

@@ -5,7 +5,9 @@
 
 setup(
     name='taskgraph',
-    natcap_version='taskgraph/version.py',
+    use_scm_version={'version_scheme': 'post-release',
+                     'local_scheme': 'node-and-date'},
+    setup_requires=['setuptools_scm'],
     description='Parallel task graph framework.',
     long_description=README,
     maintainer='Rich Sharp',