1 files changed, 67 insertions, 0 deletions
diff --git a/lib/spack/external/nose/plugins/debug.py b/lib/spack/external/nose/plugins/debug.py
new file mode 100644
index 0000000000..78243e60d0
--- /dev/null
+++ b/lib/spack/external/nose/plugins/debug.py
@@ -0,0 +1,67 @@
+"""
+This plugin provides ``--pdb`` and ``--pdb-failures`` options. The ``--pdb``
+option will drop the test runner into pdb when it encounters an error. To
+drop into pdb on failure, use ``--pdb-failures``.
+"""
+
+import pdb
+from nose.plugins.base import Plugin
+
+class Pdb(Plugin):
+    """
+    Provides --pdb and --pdb-failures options that cause the test runner to
+    drop into pdb if it encounters an error or failure, respectively.
+    """
+    enabled_for_errors = False
+    enabled_for_failures = False
+    score = 5 # run last, among builtins
+    
+    def options(self, parser, env):
+        """Register commandline options.
+        """
+        parser.add_option(
+            "--pdb", action="store_true", dest="debugBoth",
+            default=env.get('NOSE_PDB', False),
+            help="Drop into debugger on failures or errors")
+        parser.add_option(
+            "--pdb-failures", action="store_true",
+            dest="debugFailures",
+            default=env.get('NOSE_PDB_FAILURES', False),
+            help="Drop into debugger on failures")
+        parser.add_option(
+            "--pdb-errors", action="store_true",
+            dest="debugErrors",
+            default=env.get('NOSE_PDB_ERRORS', False),
+            help="Drop into debugger on errors")
+
+    def configure(self, options, conf):
+        """Configure which kinds of exceptions trigger plugin.
+        """
+        self.conf = conf
+        self.enabled_for_errors = options.debugErrors or options.debugBoth
+        self.enabled_for_failures = options.debugFailures or options.debugBoth
+        self.enabled = self.enabled_for_failures or self.enabled_for_errors
+
+    def addError(self, test, err):
+        """Enter pdb if configured to debug errors.
+        """
+        if not self.enabled_for_errors:
+            return
+        self.debug(err)
+
+    def addFailure(self, test, err):
+        """Enter pdb if configured to debug failures.
+        """
+        if not self.enabled_for_failures:
+            return
+        self.debug(err)
+
+    def debug(self, err):
+        import sys # FIXME why is this import here?
+        ec, ev, tb = err
+        stdout = sys.stdout
+        sys.stdout = sys.__stdout__
+        try:
+            pdb.post_mortem(tb)
+        finally:
+            sys.stdout = stdout