Got rid of all strings used as exceptions

4 files changed, 29 insertions, 4 deletions

diff --git a/src/nbblib/bs.py b/src/nbblib/bs.py
index cb498cb..c7a33be 100644
--- a/src/nbblib/bs.py
+++ b/src/nbblib/bs.py
@@ -43,7 +43,7 @@ class BSSourceTree(object):
     def detect(cls, vcs_tree, context):
         """Find BS tree type and return it"""
         if len(BSSourceTree.plugins) < 1:
-            raise "No BS source tree classes registered"
+            raise NoPluginsRegistered(cls)
         matches = PluginDict()
         for key, klass in BSSourceTree.plugins.items():
             try:
diff --git a/src/nbblib/main.py b/src/nbblib/main.py
index 079d743..19582ed 100644
--- a/src/nbblib/main.py
+++ b/src/nbblib/main.py
@@ -109,7 +109,20 @@ def print_version(context):
 
 def print_help(context):
     print __doc__ % context,
+    
+    
+class PropertySetAgainError(Exception):
+    def __str__(self):
+        return "Property cannot be set more than once"
+
 
+class InvalidPropertyValue(Exception):
+    def __init__(self, value):
+        super(InvalidPropertyValue, self).__init__()
+        self.value = value
+    def __str__(self):
+        return "Property cannot be set to invalid value '%s'" % self.value
+    
 
 class Property(object):
     def __init__(self, **kwargs):
@@ -126,9 +139,9 @@ class Property(object):
     def __set__(self, instance, value):
         # print "Property.__set__", instance, value
         if hasattr(self, 'value'):
-            raise "Property cannot be set more than once"
+            raise PropertySetAgainError()
         elif not self.isvalid(value):
-            raise "Property cannot be set to invalid value '%s'" % value
+            raise InvalidPropertyValue
         else:
             self.value = self.convert(value)
     def __str__(self):
diff --git a/src/nbblib/plugins.py b/src/nbblib/plugins.py
index bd6839b..1b7a653 100644
--- a/src/nbblib/plugins.py
+++ b/src/nbblib/plugins.py
@@ -1,3 +1,6 @@
+import sys
+
+
 class DuplicatePluginName(Exception):
     pass
 
@@ -35,6 +38,15 @@ class PluginDict(object):
 # Slightly modified go store plugins as dict.
 ########################################################################
 
+
+class NoPluginsRegistered(Exception):
+    def __init__(self, cls):
+        super(NoPluginsRegistered, self).__init__()
+        self.cls = cls
+    def __str__(self):
+        return "No %s plugins registered" % (self.cls.__name__)
+    
+
 class GenericPluginMeta(type):
     def __init__(cls, name, bases, attrs):
         if not hasattr(cls, 'plugins'):
diff --git a/src/nbblib/vcs.py b/src/nbblib/vcs.py
index b0aee5b..a3e4867 100644
--- a/src/nbblib/vcs.py
+++ b/src/nbblib/vcs.py
@@ -73,7 +73,7 @@ class VCSourceTree(object):
     def detect(cls, srcdir, context):
         """Detect VCS tree type and return object representing it"""
         if len(VCSourceTree.plugins) < 1:
-            raise "No VC source tree classes registered"
+            raise NoPluginsRegistered(cls)
         matches = PluginDict()
         for key, klass in VCSourceTree.plugins.items():
             try: