- Improved error handling. No longer show tracebacks for user errors.

- Now require a recipe option (and therefore a section) for every part.

README.txt

@@ -189,6 +189,13 @@ You can send questions to jim@zope.com.
 Change History
 ==============
 
+1.0.0b3
+-------
+
+- Improved error handling.  No longer show tracebacks for user errors.
+
+- Now require a recipe option (and therefore a section) for every part.
+
 1.0.0b2
 -------
 

src/zc/buildout/buildout.py

@@ -29,10 +29,21 @@ import zc.buildout.easy_install
 import pkg_resources
 import zc.buildout.easy_install
 
-class MissingOption(KeyError):
+class UserError(Exception):
+    """Errors made by a user 
+    """
+
+    def __str__(self):
+        return " ".join(map(str, self))
+
+class MissingOption(UserError, KeyError):
     """A required option was missing
     """
 
+class MissingSection(UserError, KeyError):
+    """A required section is missinh
+    """
+
 class Options(dict):
 
     def __init__(self, buildout, section, data):
@@ -44,7 +55,8 @@ class Options(dict):
         try:
             return super(Options, self).__getitem__(option)
         except KeyError:
-            raise MissingOption("Missing option", self.section, option)
+            raise MissingOption("Missing option: %s:%s"
+                                % (self.section, option))
 
     # XXX need test
     def __setitem__(self, option, value):
@@ -133,7 +145,12 @@ class Buildout(dict):
         if r is not None:
             return r
         if key in seen:
-            raise ValueError('Circular references', seen, key)
+            raise UserError("Circular reference in substitutions.\n"
+                            "We're evaluating %s\nand are referencing: %s.\n"
+                            % (", ".join([":".join(k) for k in seen]),
+                               ":".join(key)
+                               )
+                            )
         seen.append(key)
         value = '$$'.join([self._dosubs_esc(s, data, converted, seen)
                            for s in value.split('$$')
@@ -151,10 +168,12 @@ class Buildout(dict):
             if v is None:
                 options = data.get(s[0])
                 if options is None:
-                    raise KeyError("Referenced section does not exist", s[0])
+                    raise MissingSection(
+                        "Referenced section does not exist", s[0])
                 v = options.get(s[1])
                 if v is None:
-                    raise KeyError("Referenced option does not exist", *s)
+                    raise MissingOption("Referenced option does not exist:",
+                                        *s)
                 if '$' in v:
                     v = self._dosubs(s[0], s[1], v, data, converted, seen)
                     options[s[1]] = v
@@ -335,7 +354,8 @@ class Buildout(dict):
         for part in parts:
             options = self.get(part)
             if options is None:
-                options = self[part] = {}
+                raise MissingSection("No section was specified for part", part)
+
             recipe, entry = self._recipe(part, options)
             recipes_requirements.append(recipe)
 
@@ -382,7 +402,7 @@ class Buildout(dict):
             options['__buildout_signature__'] = ' '.join(sig)
 
     def _recipe(self, part, options):
-        recipe = options.get('recipe', part)
+        recipe = options['recipe']
         if ':' in recipe:
             recipe, entry = recipe.split(':')
         else:
@@ -528,7 +548,7 @@ def _open(base, filename, seen):
 
     filename = os.path.join(base, filename)
     if filename in seen:
-        raise ValueError("Recursive file include", seen, filename)
+        raise UserError("Recursive file include", seen, filename)
 
     base = os.path.dirname(filename)
     seen.append(filename)
@@ -592,7 +612,7 @@ def _update(d1, d2):
     return d1
 
 def _error(*message):
-    sys.stderr.write(' '.join(message) +'\n')
+    sys.stderr.write('Error: ' + ' '.join(message) +'\n')
     sys.exit(1)
 
 def main(args=None):
@@ -612,9 +632,6 @@ def main(args=None):
                 else:
                     verbosity -= 10
                 op = op[1:]
-            if op == 'd':
-                op = op[1:]
-                import pdb; pdb.set_trace()
                 
             if op[:1] == 'c':
                 op = op[1:]
@@ -641,8 +658,11 @@ def main(args=None):
     if verbosity:
         options.append(('buildout', 'verbosity', str(verbosity)))
 
-    buildout = Buildout(config_file, options)
-    buildout._setup_logging()
+    try:
+        buildout = Buildout(config_file, options)
+        buildout._setup_logging()
+    except UserError, v:
+        _error(str(v))
 
     if args:
         command = args.pop(0)
@@ -652,9 +672,13 @@ def main(args=None):
         command = 'install'
 
     try:
-        getattr(buildout, command)(args)
+        try:
+            getattr(buildout, command)(args)
+        except UserError, v:
+            _error(str(v))
+            
     finally:
-        logging.shutdown()
+            logging.shutdown()
 
 if sys.version_info[:2] < (2, 4):
     def reversed(iterable):

src/zc/buildout/buildout.txt

@@ -255,8 +255,9 @@ buildout and recipes are doing.
     recipe = recipes:mkdir
     path = mystuff    
 
-Generally, when we name a part, we also create a section of the same
-name that contains part data.  In this section, we'll usually define
+
+When we name a part, we also create a section of the same
+name that contains part data.  In this section, we'll define
 the recipe to be used to install the part.  In this case, we also
 specify the path to be created.
 

src/zc/buildout/tests.py

@@ -39,7 +39,7 @@ Asking for an option that doesn't exist, a MissingOption error is raised:
     >>> buildout['buildout']['eek']
     Traceback (most recent call last):
     ...
-    MissingOption: ('Missing option', 'buildout', 'eek')
+    MissingOption: Missing option: buildout:eek
 
 It is an error to create a variable-reference cycle:
 
@@ -55,11 +55,36 @@ It is an error to create a variable-reference cycle:
 
     >>> print system(os.path.join(sample_buildout, 'bin', 'buildout')),
     ... # doctest: +NORMALIZE_WHITESPACE +ELLIPSIS
-    Traceback (most recent call last):
+    Error: Circular reference in substitutions.
+    We're evaluating buildout:y, buildout:z, buildout:x
+    and are referencing: buildout:y.
+
+Al parts have to have a section:
+
+    >>> write(sample_buildout, 'buildout.cfg',
+    ... '''
+    ... [buildout]
+    ... parts = x
+    ... ''')
+
+    >>> print system(os.path.join(sample_buildout, 'bin', 'buildout')),
+    Error: No section was specified for part x
+
+and all parts have to have a specified recipe:
+
+
+    >>> write(sample_buildout, 'buildout.cfg',
+    ... '''
+    ... [buildout]
+    ... parts = x
     ...
-    ValueError: ('Circular references',
-           [('buildout', 'y'), ('buildout', 'z'), ('buildout', 'x')],
-           ('buildout', 'y'))
+    ... [x]
+    ... foo = 1
+    ... ''')
+
+    >>> print system(os.path.join(sample_buildout, 'bin', 'buildout')),
+    Error: Missing option: x:recipe
+
 """
  
 def test_comparing_saved_options_with_funny_characters():