Merge pull request #185 from jbohren-forks/cache-resultspace

optimization: caching resultspace environments

catkin_tools/resultspace.py

@@ -9,8 +9,11 @@
 CMAKE_EXEC = which('cmake')
 SORT_EXEC = which('sort')
 
+# Cache for result-space environments
+_resultspace_env_cache = {}
 
-def get_resultspace_environment(result_space_path, quiet=False):
+
+def get_resultspace_environment(result_space_path, quiet=False, cached=True):
     """Get the environemt variables which result from sourcing another catkin
     workspace's setup files as the string output of `cmake -E environment`.
     This command is used to be as portable as possible.
@@ -19,9 +22,16 @@ def get_resultspace_environment(result_space_path, quiet=False):
     :type result_space_path: str
     :param quiet: don't throw exceptions, ``bool``
     :type quiet: bool
+    :param cached: use the cached environment
+    :type cached: bool
 
     :returns: a dictionary of environment variables and their values
     """
+
+    # Check the cache first
+    if cached and result_space_path in _resultspace_env_cache:
+        return _resultspace_env_cache[result_space_path]
+
     # Check to make sure result_space_path is a valid directory
     if not os.path.isdir(result_space_path):
         if quiet:
@@ -94,15 +104,19 @@ def get_resultspace_environment(result_space_path, quiet=False):
         print("WARNING: Failed to extract environment from resultspace: %s: %s" % (result_space_path, str(err)))
         return {}
 
+    _resultspace_env_cache[result_space_path] = env_dict
+
     return env_dict
 
 
-def load_resultspace_environment(result_space_path):
+def load_resultspace_environment(result_space_path, cached=True):
     """Load the environemt variables which result from sourcing another
     workspace path into this process's environment.
 
     :param result_space_path: path to a Catkin result-space whose environment should be loaded, ``str``
     :type result_space_path: str
+    :param cached: use the cached environment
+    :type cached: bool
     """
-    env_dict = get_resultspace_environment(result_space_path)
+    env_dict = get_resultspace_environment(result_space_path, cached=cached)
     os.environ.update(env_dict)