Move path/commit validation into GitFileHistory

This definitely belongs in the model layer, not in the executable.

Author: georgebrock

bin/git-browse

@@ -7,21 +7,16 @@ import argparse
 sys.path.append(os.path.join(os.path.dirname(__file__), '..'))
 
 from gitbrowse.browser import GitBrowser
-from gitbrowse import git
 
 
 parser = argparse.ArgumentParser(add_help=False)
 parser.add_argument('rev', nargs='?', default='HEAD')
 parser.add_argument('file')
 args = parser.parse_args()
 
-if not git.verify_revision(args.rev):
-    sys.exit(1)
+try:
+    browser = GitBrowser(args.file, args.rev)
+except ValueError as err:
+    sys.exit(str(err))
 
-if not git.verify_file(args.file):
-    sys.exit("'%s' either does not exist, or is not tracked by git" % (
-        args.file
-    ))
-
-browser = GitBrowser(args.file, args.rev)
 browser.run()

gitbrowse/git.py

@@ -35,8 +35,13 @@ class GitFileHistory(object):
     """
 
     def __init__(self, path, start_commit):
-        #TODO Validate path
-        #TODO Validate commit
+        if not verify_revision(start_commit):
+            raise ValueError('%s is not a valid commit, branch, tag, etc.' % (
+                start_commit,
+            ))
+
+        if not verify_file(path):
+            raise ValueError('"%s" is not tracked by git' % (path, ))
 
         self.path = path