Ditch $PIPE_OUTPUT_ROOT as dafault output

$PIPE_OUTPUT_ROOT should be a parent directory. Stop using it
as a default output directory if --output or --rerun not specified.

python/lsst/pipe/base/argumentParser.py

@@ -462,6 +462,12 @@ def parse_args(self, config, args=None, log=None, override=None):
 
         obeyShowArgument(namespace.show, namespace.config, exit=False)
 
+        # No environment variable or --output or --rerun specified.
+        if self.requireOutput and namespace.output is None and namespace.rerun is None:
+            self.error("no output directory specified.\n"
+                       "An output directory must be specified with the --output or --rerun\n"
+                       "command-line arguments.\n")
+
         namespace.butler = dafPersist.Butler(
             root = namespace.input,
             calibRoot = namespace.calib,
@@ -496,12 +502,6 @@ def parse_args(self, config, args=None, log=None, override=None):
         namespace.config.validate()
         namespace.config.freeze()
 
-        # No environment variable or --output or --rerun specified.
-        if self.requireOutput and namespace.output is None and namespace.rerun is None:
-            self.error("no output directory specified.\n"
-                       "An output directory must be specified with the --output or --rerun\n"
-                       "command-line arguments or the PIPE_OUTPUT_ROOT environment variable.\n")
-
         return namespace
 
     def _parseDirectories(self, namespace):
@@ -516,10 +516,8 @@ def _parseDirectories(self, namespace):
         # If an output directory is specified, process it and assign it to the namespace
         if namespace.rawOutput:
             namespace.output = _fixPath(DEFAULT_OUTPUT_NAME, namespace.rawOutput)
-        # This catches the case where the output was not specified, but _fixPath must still
-        # be run as there may be an environment variable set for the output
         else:
-            namespace.output = _fixPath(DEFAULT_OUTPUT_NAME, namespace.rawOutput)
+            namespace.output = None
 
         # This section processes the rerun argument, if rerun is specified as a colon separated
         # value, it will be parsed as an input and output. The input value will be overridden if

tests/testArgumentParser.py

@@ -358,7 +358,7 @@ def testPipeVars(self):
         )
         self.assertEqual(namespace.input, os.path.abspath(DataPath))
         self.assertEqual(namespace.calib, None)
-        self.assertEqual(namespace.output, os.path.abspath(DataPath))
+        self.assertEqual(namespace.output, None)
 
     def testBareHelp(self):
         """Make sure bare help does not print an error message (ticket #3090)
@@ -469,6 +469,7 @@ def testConfigDatasetTypeNoFieldDefault(self):
         """Test ConfigDatasetType with a config field that has no default value"""
         name = "dsTypeNoDefault"
         ap = pipeBase.ArgumentParser(name="argumentParser")
+        ap.requireOutput = False  # Allow simpler command-line
         dsType = pipeBase.ConfigDatasetType(name=name)
 
         ap.add_id_argument("--id", dsType, "help text")
@@ -496,16 +497,6 @@ def testOutputs(self):
         self.assertEqual(args.output, path)
         self.assertIsNone(args.rerun)
 
-        # Specified by environment variable
-        try:
-            os.environ["PIPE_OUTPUT_ROOT"] = path
-            args = parser.parse_args(config=self.config, args=[DataPath,])
-            self.assertEqual(args.input, DataPath)
-            self.assertEqual(args.output, path)
-            self.assertIsNone(args.rerun)
-        finally:
-            os.environ.pop("PIPE_OUTPUT_ROOT", None)
-
         # Specified by rerun
         args = parser.parse_args(config=self.config, args=[DataPath, "--rerun", "foo"])
         self.assertEqual(args.input, DataPath)