Rework command framework

Implies catching exceptions in a single place.

6 files changed, 124 insertions, 106 deletions

diff --git a/TODO b/TODO
index 3fb0272..e9ab673 100644
--- a/TODO
+++ b/TODO
@@ -6,7 +6,8 @@ TODO: (to get git-amb equivalent functionality)
    * Write docs: man page equivalent, README, and HACKING.
 
 TODO: (Large list)
- * Move command objects to plugin detection framework
+ * Switch plugins.Foo.validate() functions to different protocol:
+   Either return or raise an exception.
  * supports execution of user commands in source, build, install dirs
  * BS support: cmake, scons, ...
  * VCS support: SVN, darcs, hg, ...
@@ -33,6 +34,7 @@ TODO: (Large list)
  * Man page or something similar. Generate from help texts?
 
 DONE:
+ * Do not move command objects to plugin detection framework (bad idea!)
  * Find or implement @abstractmethod decorator.
  * Unify detect() methods.
  * Design nice user interface. Requirements:
diff --git a/src/nbblib/bs.py b/src/nbblib/bs.py
index f8f247c..f9215a2 100644
--- a/src/nbblib/bs.py
+++ b/src/nbblib/bs.py
@@ -76,7 +76,9 @@ class BSSourceTree(plugins.GenericDetectPlugin):
 
 
 class AutomakeSourceTree(BSSourceTree):
+
     name = 'automake'
+
     def __init__(self, context, vcs_tree):
         super(AutomakeSourceTree, self).__init__(context)
         srcdir = vcs_tree.tree_root
@@ -130,7 +132,9 @@ class AutomakeSourceTree(BSSourceTree):
 
 
 class SconsSourceTree(BSSourceTree):
+
     name = 'scons'
+
     def __init__(self, context, vcs_tree):
         super(SconsSourceTree, self).__init__(context)
         srcdir = vcs_tree.tree_root
diff --git a/src/nbblib/commands.py b/src/nbblib/commands.py
index e5eab40..2e653b6 100644
--- a/src/nbblib/commands.py
+++ b/src/nbblib/commands.py
@@ -15,7 +15,7 @@ import nbblib.vcs as vcs
 import nbblib.bs as bs
 
 
-__all__ = []
+__all__ = ['Commander']
 
 
 def adjust_doc(doc):
@@ -36,18 +36,23 @@ def adjust_doc(doc):
 
 __all__.append('CommandLineError')
 class CommandLineError(Exception):
-    def __init__(self, message, *args, **kwargs):
+    def __init__(self, message):
         super(CommandLineError, self).__init__()
-        if args:
-            self.msg = message % args
-        elif kwargs:
-            self.msg = message % kwargs
-        else:
-            self.msg = message
+        self.msg = message
     def __str__(self):
         return "Command line error: %s" % self.msg
 
 
+__all__.append('UnknownCommand')
+class UnknownCommand(Exception):
+    def __init__(self, context, cmd):
+        super(UnknownCommand, self).__init__()
+        self.prog = context.prog
+        self.cmd = cmd
+    def __str__(self):
+        return "Unknown %(prog)s command '%(cmd)s'" % self.__dict__
+
+
 ########################################################################
 # Command plugin system
 ########################################################################
@@ -81,27 +86,44 @@ class Command(object):
 
     usage = ''
 
-    def __init__(self, *args, **kwargs):
+    def __init__(self, context, *args, **kwargs):
         super(Command, self).__init__()
         self.validate_args(*args, **kwargs)
         self.args = args
         self.kwargs = kwargs
-        self.context = kwargs['context']
+        self.context = context
 
     @plugins.abstractmethod
     def run(self):
         """Run the command"""
         pass
 
-    # Candidate for abstractmethod
-    def validate_args(self, *args, **kwargs):
-        """Validate command line arguments"""
-        print "Command: ", self.name
-        print "*args:   ", args
-        print "**kwargs:", kwargs
-        if len(args) > 0:
+    @plugins.abstractmethod
+    def validate_args(self, *cmdargs, **kwargs):
+        """Validate command line arguments: Abstract method.
+
+        May make use of self.context.
+        """
+        pass
+
+    def validate_args_none(self, *cmdargs, **kwargs):
+        """Validate command line arguments: no argument at all"""
+        logging.debug("Command:  %s", self.name)
+        logging.debug("*cmdargs: %s", cmdargs)
+        logging.debug("**kwargs: %s", kwargs)
+        if len(cmdargs) > 0:
             raise CommandLineError("'%s' command takes no parameters",
                                    self.name)
+        logging.debug("Command match!")
+        return True
+
+    def validate_args_any(self, *cmdargs, **kwargs):
+        """Validate command line arguments: accept any argument"""
+        logging.debug("Command:  %s", self.name)
+        logging.debug("*cmdargs: %s", cmdargs)
+        logging.debug("**kwargs: %s", kwargs)
+        logging.debug("Command match!")
+        return True
 
     def __str__(self):
         return "Command(%s, %s)" % (self.cmd_name, self.cmdargs)
@@ -127,8 +149,7 @@ class HelpCommand(Command):
         print "List of commands:"
         keys = Command.plugins.keys()
         if not keys:
-            print "Error: No commands found."
-            sys.exit(2)
+            raise Exception("No commands found. Please lart the developer.")
         keys.sort()
         keys2 = Command.plugins.keys()
 	keys2.sort(lambda a,b: cmp(len(b),len(a)))
@@ -163,6 +184,7 @@ class HelpCommand(Command):
 class InternalConfigCommand(Command):
     name = 'internal-config'
     summary = 'print internal program configuration'
+    validate_args = Command.validate_args_none
     def run(self):
         print "Source tree types:",  ", ".join(vcs.VCSourceTree.plugins.keys())
         print "Build system types:", ", ".join(bs.BSSourceTree.plugins.keys())
@@ -172,10 +194,9 @@ class InternalConfigCommand(Command):
 class SourceClassCommand(Command):
     """Base class for commands acting on source trees"""
     name = None # abstract command class
-    def __init__(self, *args, **kwargs):
-        super(SourceClassCommand, self).__init__(*args, **kwargs)
+    def __init__(self, context, *args, **kwargs):
+        super(SourceClassCommand, self).__init__(context, *args, **kwargs)
 
-        context = kwargs['context']
         srcdir = os.getcwd()
         absdir = os.path.abspath(srcdir)
 
@@ -193,20 +214,18 @@ class SourceClassCommand(Command):
 
 class DetectCommand(Command):
     name = None
-    def __init__(self, *args, **kwargs):
-        super(DetectCommand, self).__init__(*args, **kwargs)
-        self.context = kwargs['context']
+    def __init__(self, context, *args, **kwargs):
+        super(DetectCommand, self).__init__(context, *args, **kwargs)
         self.srcdir = os.getcwd()
         self.absdir = os.path.abspath(self.srcdir)
-    def validate_args(self, *args, **kwargs):
-        pass
+    validate_args = Command.validate_args_none
 
 
 class DetectVCSCommand(DetectCommand):
     name = "detect-vcs"
     summary = "detect source tree VCS"
-    def __init__(self, *args, **kwargs):
-        super(DetectVCSCommand, self).__init__(*args, **kwargs)
+    def __init__(self, context, *args, **kwargs):
+        super(DetectVCSCommand, self).__init__(context, *args, **kwargs)
         self.vcs_sourcetree = vcs.VCSourceTree.detect(self.context, self.absdir)
         logging.debug("vcs_sourcetree %s", self.vcs_sourcetree)
     def run(self):
@@ -214,13 +233,14 @@ class DetectVCSCommand(DetectCommand):
             print 'VCS:', self.vcs_sourcetree.name, self.vcs_sourcetree.tree_root
         else:
             print 'VCS:', 'Not detected'
+    validate_args = Command.validate_args_none
 
 
 class DetectBSCommand(DetectCommand):
     name = "detect-bs"
     summary = "detect source tree BS"
-    def __init__(self, *args, **kwargs):
-        super(DetectBSCommand, self).__init__(*args, **kwargs)
+    def __init__(self, context, *args, **kwargs):
+        super(DetectBSCommand, self).__init__(context, *args, **kwargs)
         self.vcs_sourcetree = vcs.VCSourceTree.detect(self.context, self.absdir)
         logging.debug("vcs_sourcetree %s", self.vcs_sourcetree)
         self.bs_sourcetree = bs.BSSourceTree.detect(self.context,
@@ -231,6 +251,7 @@ class DetectBSCommand(DetectCommand):
             print 'BS:', self.bs_sourcetree.name, self.bs_sourcetree.tree_root
         else:
             print 'BS:', 'Not detected'
+    validate_args = Command.validate_args_none
 
 
 class BuildTestCommand(SourceClassCommand):
@@ -241,49 +262,37 @@ class BuildTestCommand(SourceClassCommand):
         self.bs_sourcetree.configure()
         self.bs_sourcetree.build()
         self.bs_sourcetree.install()
+    validate_args = Command.validate_args_none
 
 
 class InitCommand(SourceClassCommand):
     name = 'init'
     summary = 'initialize buildsystem'
-    def validate_args(self, *args, **kwargs):
-        """Validate command line arguments"""
-        if len(args) > 0:
-            raise CommandLineError("'%s' command takes no parameters",
-                                   self.name)
+    validate_args = Command.validate_args_none
     def run(self):
         self.bs_sourcetree.init()
 
+
 class ConfigureCommand(SourceClassCommand):
     name = 'configure'
     summary = 'configure buildsystem'
-    def validate_args(self, *args, **kwargs):
-        """Validate command line arguments"""
-        if len(args) > 0:
-            raise CommandLineError("'%s' command takes no parameters",
-                                   self.name)
+    validate_args = Command.validate_args_none
     def run(self):
         self.bs_sourcetree.configure()
 
+
 class BuildCommand(SourceClassCommand):
     name = 'build'
     summary = 'build from source'
-    def validate_args(self, *args, **kwargs):
-        """Validate command line arguments"""
-        if len(args) > 0:
-            raise CommandLineError("'%s' command takes no parameters",
-                                   self.name)
+    validate_args = Command.validate_args_none
     def run(self):
         self.bs_sourcetree.build()
 
+
 class InstallCommand(SourceClassCommand):
     name = 'install'
     summary = 'install the built things'
-    def validate_args(self, *args, **kwargs):
-        """Validate command line arguments"""
-        if len(args) > 0:
-            raise CommandLineError("'%s' command takes no parameters",
-                                   self.name)
+    validate_args = Command.validate_args_none
     def run(self):
         self.bs_sourcetree.install()
 
@@ -291,8 +300,7 @@ class InstallCommand(SourceClassCommand):
 class MakeCommand(SourceClassCommand):
     name = 'make'
     summary = 'run make in builddir'
-    def validate_args(self, *args, **kwargs):
-        pass
+    validate_args = Command.validate_args_any
     def run(self):
         os.chdir(self.bs_sourcetree.config.builddir)
         progutils.prog_run(["make"] + list(self.args),
@@ -340,34 +348,17 @@ class ConfigCommand(SourceClassCommand):
             assert(False)
 
 
-########################################################################
-# Commands
-########################################################################
-
+class Commander(object):
 
-__all__.append('UnknownCommand')
-class UnknownCommand(Exception):
-    def __init__(self, cmd):
-        super(UnknownCommand, self).__init__()
-        self.cmd = cmd
-    def __str__(self):
-        return "Fatal: Unknown command '%(cmd)s'" % self.__dict__
-
-
-__all__.append('NBB_Command')
-class NBB_Command(object):
-    def __init__(self, cmd, cmdargs, context):
+    def __init__(self, context, cmd, *cmdargs):
+        self.context = context
+        logging.debug("Commander() %s %s", cmd, cmdargs)
         if cmd in Command.plugins:
-            try:
-                c = Command.plugins[cmd](*cmdargs, **{'context':context})
-                c.run()
-            except CommandLineError, e:
-                print "%(prog)s: Fatal:" % context, e
-                sys.exit(2)
-            except progutils.ProgramRunError, e:
-                print "%(prog)s: Fatal:" % context, e
-                sys.exit(3)
+            self.command = Command.plugins[cmd](context, *cmdargs)
         else:
-            print "%(prog)s:" % context, UnknownCommand(cmd)
-            sys.exit(2)
+            raise UnknownCommand(context, cmd)
+
+    def run(self):
+        self.command.run()
 
+# End of file.
diff --git a/src/nbblib/main.py b/src/nbblib/main.py
index fabbdad..22c93e3 100644
--- a/src/nbblib/main.py
+++ b/src/nbblib/main.py
@@ -75,6 +75,7 @@ from nbblib import commands
 from nbblib import package
 from nbblib import plugins
 from nbblib import vcs
+from nbblib import progutils
 
 
 def print_version(context):
@@ -206,14 +207,13 @@ def main(argv):
 
     if len(argv) < 2:
         raise commands.CommandLineError(\
-            "%(prog)s requires some arguments",
-            prog=context.prog)
+            "%(prog)s requires some arguments" % context)
 
     i = 1
     while i<len(argv):
         if argv[i][0] != '-':
             break
-        if argv[i] in ('-h', '--help'):
+        elif argv[i] in ('-h', '--help'):
             print_help(context)
             return
         elif argv[i] in ('-V', '--version'):
@@ -225,7 +225,7 @@ def main(argv):
             i = i + 1
             assert(i<len(argv))
             context.bs = argv[i]
-        elif argv[i][:6] == '--build-system=':
+        elif argv[i][:15] == '--build-system=':
             context.bs = argv[i][6:]
         elif argv[i] in ('-v', '--vcs'):
             i = i + 1
@@ -236,32 +236,44 @@ def main(argv):
         elif argv[i] in ('--info', '--debug'):
             pass # acted on in previous stage
         else:
-            raise commands.CommandLineError('Unknown global option %s' % repr(argv[i]))
-        # print "", i, argv[i]
+            raise commands.CommandLineError(\
+                'Unknown global option %s' % repr(argv[i]))
         i = i + 1
+
     logging.info("Context: %s", context)
     cmd = argv[i]
     cmdargs = argv[i+1:]
-    nbb = commands.NBB_Command(cmd, cmdargs, context=context)
+
+    cdr = commands.Commander(context, cmd, *cmdargs)
+    cdr.run()
 
 
 def cmdmain(argv):
     try:
         main(argv)
         logging.shutdown()
+    except commands.CommandLineError, e:
+        logging.error(e)
+        logging.shutdown()
+        sys.exit(2)
+    except commands.UnknownCommand, e:
+        logging.error(e)
+        logging.shutdown()
+        sys.exit(2)
     except plugins.PluginNoMatch, e:
+        logging.error(e)
         logging.shutdown()
-        print e
         sys.exit(1)
     except plugins.AmbigousPluginDetection, e:
+        logging.error(e)
         logging.shutdown()
-        print e
         sys.exit(1)
-    except commands.CommandLineError, e:
+    except progutils.ProgramRunError, e:
+        logging.error(e)
         logging.shutdown()
-        print e
-        sys.exit(2)
+        sys.exit(3)
     except SystemExit, e:
+        logging.error("Someone called sys.exit() who should not have", exc_info=e)
         logging.shutdown()
         raise
 
diff --git a/test/nbb-basic.at b/test/nbb-basic.at
index 4da4795..81ebf09 100644
--- a/test/nbb-basic.at
+++ b/test/nbb-basic.at
@@ -33,9 +33,18 @@ dnl ===================================================================
 
 AT_SETUP([nbb basic: no parameters at all])
 AT_KEYWORDS([nbb no parameters])
-AT_CHECK([AT_NBB], [2],
-[Command line error: nbb requires some arguments
-], [])
+AT_CHECK([AT_NBB], [2], [], 
+[ERROR: Command line error: nbb requires some arguments
+])
+AT_CLEANUP()
+
+dnl ===================================================================
+
+AT_SETUP([nbb basic: unknown command])
+AT_KEYWORDS([nbb unknown command])
+AT_CHECK([AT_NBB this-command-does-not-exist], [2], [],
+[ERROR: Unknown nbb command 'this-command-does-not-exist'
+])
 AT_CLEANUP()
 
 dnl ===================================================================
diff --git a/test/nbb-detect.at b/test/nbb-detect.at
index 0ca3176..d5458f4 100644
--- a/test/nbb-detect.at
+++ b/test/nbb-detect.at
@@ -8,8 +8,8 @@ dnl ===================================================================
 AT_SETUP([nbb detect-vcs: no VCS repository type])
 AT_KEYWORDS([nbb detect vcs])
 AT_CHECK([mkdir test.foo && cd test.foo])
-AT_CHECK([echo "Unknown VCS source tree type: '$PWD/test.foo'" > expout
-cd test.foo && AT_NBB detect-vcs], [1], [expout])
+AT_CHECK([echo "ERROR: Unknown VCS source tree type: '$PWD/test.foo'" > experr
+cd test.foo && AT_NBB detect-vcs], [1], [], [experr])
 AT_CHECK([rm -rf test.foo])
 AT_CLEANUP()
 
@@ -46,11 +46,11 @@ AT_CHECK([cd test.bzrgit && bzr init && bzr nick testnick])
 AT_CHECK([cd test.bzrgit && git init], [0],
 [Initialized empty Git repository in .git/
 ])
-AT_CHECK([echo "Ambigous VCS types detected for '$PWD/test.bzrgit':
+AT_CHECK([echo "ERROR: Ambigous VCS types detected for '$PWD/test.bzrgit':
   VCS type  Branch name
   git       master
-  bzr       testnick" > expout
-cd test.bzrgit && AT_NBB detect-vcs], [1], [expout])
+  bzr       testnick" > experr
+cd test.bzrgit && AT_NBB detect-vcs], [1], [], [experr])
 AT_CHECK([rm -rf test.bzrgit])
 AT_CLEANUP()
 
@@ -102,10 +102,10 @@ AC[_]OUTPUT
 AT_DATA([test.git/SConstruct], [dnl
 # Test
 ])
-AT_CHECK([echo "Ambigous BS types detected for '$PWD/test.git':
+AT_CHECK([echo "ERROR: Ambigous BS types detected for '$PWD/test.git':
   automake
-  scons" > expout
-cd test.git && AT_NBB detect-bs], [1], [expout])
+  scons" > experr
+cd test.git && AT_NBB detect-bs], [1], [], [experr])
 AT_CHECK([rm -rf test.git])
 AT_CLEANUP()
 
@@ -117,8 +117,8 @@ AT_CHECK([mkdir test.git && cd test.git])
 AT_CHECK([cd test.git && git init], [0],
 [Initialized empty Git repository in .git/
 ])
-AT_CHECK([echo "Unknown BS source tree type: '$PWD/test.git'" > expout
-cd test.git && AT_NBB detect-bs], [1], [expout])
+AT_CHECK([echo "ERROR: Unknown BS source tree type: '$PWD/test.git'" > experr
+cd test.git && AT_NBB detect-bs], [1], [], [experr])
 AT_CHECK([rm -rf test.git])
 AT_CLEANUP()