inconsistent error handling

[Michael Ching]

read-only pages do not raise a TracError when there are insufficient privileges. In the case of an unprivileged user, they will see a grayed out form for readonly pages, but an error for normal pages.

One of the following changes should make it consistent. We opted for simply removing the TracError because it seems more graceful to show the grayed out form rather than an error.

From:

        if page.readonly:
            if 'WIKI_ADMIN' in req.perm(resource):
                cancomment = True
        elif 'WIKI_MODIFY' in req.perm(resource):
            cancomment = True
        elif appendonly and 'WIKI_VIEW' in req.perm(resource):
            cancomment = True
        else:
            raise TracError('Error: Insufficient privileges to AddComment')

To:

        if page.readonly:
            if 'WIKI_ADMIN' in req.perm(resource):
                cancomment = True
        elif 'WIKI_MODIFY' in req.perm(resource):
            cancomment = True
        elif appendonly and 'WIKI_VIEW' in req.perm(resource):
            cancomment = True

Or:

        if page.readonly:
            if 'WIKI_ADMIN' in req.perm(resource):
                cancomment = True
            else:
                raise TracError('Error: Insufficient privileges to AddComment')
        elif 'WIKI_MODIFY' in req.perm(resource):
            cancomment = True
        elif appendonly and 'WIKI_VIEW' in req.perm(resource):
            cancomment = True
        else:
            raise TracError('Error: Insufficient privileges to AddComment')

[Oliver Metz]

Display greyed out comment box instead of macro error

[osimons]

(In [8745]) AddCommentMacro: Not raise an error for permission issue. Render the form with all fields disabled instead. Closes #4959.