report error messages in annotated_builder.py

[inglorion]

Summary

annotated_builder.py's report_step_exception() function would emit a
buildbot @@@STEP_EXCEPTION@@@ annotation, but had no way to report an
error message. This change adds that functionality and makes
annotated_builder.py use it. I also spotted and removed a redundant
check around a call to util.clean_dir().

[rnk]

lgtm I'm so happy that fixing this doesn't require a buildmaster restart.

zorg/trunk/zorg/buildbot/builders/annotated/annotated_builder.py

class AnnotatedBuilder:
     """
 
     def halt_on_failure(self):
         util.report('@@@HALT_ON_FAILURE@@@')
 
     def report_build_step(self, step):
         util.report('@@@BUILD_STEP %s@@@' % (step,))
 
-    def report_step_exception(self):
+    def report_step_exception(self, exn=None):
+        if exn:
+            util.report(str(exn))
         util.report('@@@STEP_EXCEPTION@@@')
 
     def build_and_check_stage(
         self,
         stage,
         build_dir,
         source_dir,
         cmake_args,
def check(self, stage_name, build_dir, check_targets, jobs=None):
         cmd += check_targets
         util.report_run_cmd(cmd, cwd=build_dir)
 
     def clean_build_dir(self, stage_name, build_dir):
         self.report_build_step('%s clean' % (stage_name,))
         self.halt_on_failure()
         try:
             util.clean_dir(build_dir)
-        except OSError as e:
-            if e.errno != errno.ENOENT:
-                self.report_step_exception()
-                raise
+        except Exception as e:
+          self.report_step_exception(e)
 
     def cmake(
         self,
         stage_name,
         build_dir,
         source_dir,
         cmake='cmake',
         cmake_args=None):
def set_environment(self, env=None, vs_tools=None, arch=None):
             if env is not None:
                 new_env.epdate(env)
 
             for (var, val) in new_env.items():
                 os.environ[var] = val
 
             for var in sorted(os.environ.keys()):
                 util.report('%s=%s' % (var, os.environ[var]))
-        except:
-            self.report_step_exception()
+        except Exception as e:
+            self.report_step_exception(e)
             raise
 
     def update_sources(self, source_dir, projects, revision=None, svn='svn'):
         self.report_build_step('update-sources')
         self.halt_on_failure()
         try:
             for (project, path, uri) in projects:
                 if path is None:
                     path = source_dir
                 elif not os.path.isabs(path):
                     path = pjoin(source_dir, path)
                 util.report(
                     "Updating %s at %s from %s" % (project, util.shquote(path), uri))
                 if revision is None:
                     revision_args = []
                 else:
                     revision_args = ['-r', revision]
                 if os.path.exists(pjoin(path, '.svn')):
                     cmd = [svn, 'up'] + revision_args
                 else:
                     util.mkdirp(path)
                     cmd = [svn, 'co'] + revision_args + [uri, '.']
                 util.report_run_cmd(cmd, cwd=path)
-        except:
-            self.report_step_exception()
+        except Exception as e:
+            self.report_step_exception(e)
             raise
 
     def run_steps(
         self,
         stages=1,
         check_targets=None,
         check_stages=None,
         extra_cmake_args=None,