review/api.py @ 789e5765c9ff

Start adding some documentation to the internals of the API.

I also managed to sneak a doctest in there which found a bug.
The bug is now fixed.
Awesome.
author Steve Losh <steve@stevelosh.com>
date Wed, 07 Oct 2009 23:38:30 -0400
parents 08528309f7cd
children 62c8ba974c19
from __future__ import with_statement

"""The data structures used by hg-review."""

import os
import messages, templates
from datetime import datetime
from mercurial import cmdutil, hg, patch
from mercurial.node import hex
from mercurial.util import sha1


class PreexistingDatastore(Exception):
    """Raised when trying to initialize a datastore when one seems to exist."""
    def __init__(self, committed):
        super(PreexistingDatastore, self).__init__()
        self.committed = committed
    

class SignoffExists(Exception):
    """Raised when trying to signoff twice without forcing."""
    pass

class CannotDeleteObject(Exception):
    """Raised when trying to delete an object that does not support deletion."""
    pass

class FileNotInChangeset(Exception):
    """Raised when trying to add a comment on a file not in the changeset."""
    def __init__(self, filename):
        super(FileNotInChangeset, self).__init__()
        self.filename = filename
    


def _split_path_dammit(p):
    """Take a file path (from the current platform) and split it.  Really.
    
    os.path doesn't seem to have an easy way to say "Split this path into a
    list of pieces."
    
    >>> _split_path_dammit('')
    []
    >>> _split_path_dammit('one')
    ['one']
    >>> _split_path_dammit('one/two/three')
    ['one', 'two', 'three']
    >>> _split_path_dammit('one/two/three/')
    ['one', 'two', 'three']
    >>> _split_path_dammit('one/two/three.py')
    ['one', 'two', 'three.py']
    
    """
    def _spd(p):
        p, i = os.path.split(p)
        while i or p:
            yield i
            p, i = os.path.split(p)
    
    return filter(None, list(_spd(p)))[::-1]

def _parse_hgrf(repo):
    """Parse the .hgreview file and return the data inside.
    
    The .hgreview file will be pulled from the tip revision of the given
    repository.  If it is not committed it will not be found!
    
    """
    data = {}
    hgrd = repo['tip']['.hgreview'].data().split('\n')
    lines = [line for line in hgrd if line.strip()]
    for line in lines:
        label, _, path = [i.strip() for i in line.partition('=')]
        if label == 'local':
            data['lpath'] = path
        elif label == 'remote':
            data['rpath'] = path
    
    return data

def _commitfunc(ui, repo, message, match, opts):
    """A function used by the guts of Mercurial.
    
    Mercurial needs a "commit function" parameter when using cmdutil.commit.
    This is a simple function for *only* that purpose.
    
    """
    return repo.commit(message, opts.get('user'), opts.get('date'), match)

def _parse_data(data):
    """Parse the data (string) of a stored _ReviewObject and return a dict."""
    meta, _, message = data.partition('\n\n')
    
    data = {}
    for m in meta.split('\n'):
        label, _, val = m.partition(':')
        data[label] = val
    data['message'] = message
    return data


def sanitize_path(p, repo=None):
    """Sanitize a (platform-specific) path.
    
    If no repository is given, the path's separators will be replaced with
    forward slashes (the form Mercurial uses internally).
    
    If a repository is given, the result will be relative to the root of the
    repository.  This is useful for turning relative paths into normalized
    paths that can be used to look up files from a changectx.
    
    This function is idempotent.  If you sanitize a path multiple times
    against the same repository the result will not change.
    
    """
    if repo:
        p = os.path.relpath(os.path.realpath(p), start=repo.root)
    return '/'.join(_split_path_dammit(p))


class ReviewDatastore(object):
    """The data store for all the reviews so far."""
    def __init__(self, ui, repo, lpath=None, rpath=None, create=False):
        self.ui = ui
        
        if not create:
            data = _parse_hgrf(repo)
            self.lpath = data['lpath']
            self.rpath = data['rpath']
        else:
            if '.hgreview' in repo['tip']:
                raise PreexistingDatastore(True)
            if os.path.exists(os.path.join(repo.root, '.hgreview')):
                raise PreexistingDatastore(False)
            self.lpath = lpath or '.review'
            self.rpath = rpath or ('../%s-review' % os.path.basename(repo.root))
        
        root = os.path.join(repo.root, self.lpath)
        self.target = repo
        self.repo = hg.repository(ui, root, create)
        
        if create:
            hgrpath = os.path.join(repo.root, '.hgreview')
            with open(hgrpath, 'w') as hgrf:
                hgrf.write('local = %s\n' % self.lpath)
                hgrf.write('remote = %s\n' % self.rpath)
            repo.add(['.hgreview'])
    
    def __getitem__(self, rev):
        """Return a ReviewChangeset for the given revision."""
        node = hex(self.target[rev].node())
        return ReviewChangeset(self.ui, self.repo, self.target, node)
    

class ReviewChangeset(object):
    """The review data about one changeset in the target repository."""
    def __init__(self, ui, repo, target, node):
        self.repo = repo
        self.target = target
        self.ui = ui
        self.node = node
        
        if '%s/.exists' % self.node in self.repo['tip']:
            _match = lambda p: lambda fn: fn.startswith(p)
            
            relevant = filter(_match(node), self.repo['tip'])
            commentfns = filter(_match('%s/comments' % node), relevant)
            signofffns = filter(_match('%s/signoffs' % node), relevant)
            
            self.comments = []
            for fn in commentfns:
                data = _parse_data(self.repo['tip'][fn].data())
                data['lines'] = data['lines'].split(',')
                data['lines'] = map(int, filter(None, data['lines']))
                self.comments.append(ReviewComment(**data))
            
            self.signoffs = []
            for fn in signofffns:
                data = _parse_data(self.repo['tip'][fn].data())
                self.signoffs.append(ReviewSignoff(**data))
        else:
            self.comments = []
            self.signoffs = []
            
            path = os.path.join(self.repo.root, self.node)
            os.mkdir(path)
            with open(os.path.join(path, '.exists'), 'w') as e:
                pass
            
            cmdutil.commit(ui, self.repo, _commitfunc,
                [os.path.join(path, '.exists')],
                { 'message': 'Initialize review data for changeset %s' % self.node,
                  'addremove': True, })
    
    def add_signoff(self, message, opinion='', force=False):
        """Add (and commit) a signoff for the given revision."""
        existing = filter(lambda s: s.author == self.ui.username(), self.signoffs)
        
        if existing:
            if not force:
                raise SignoffExists
            existing[0].delete(self.ui, self.repo)
        
        signoff = ReviewSignoff(self.ui.username(), datetime.utcnow(),
            self.node, opinion, message)
        signoff.commit(self.ui, self.repo)
    
    def add_comment(self, message, filename='', lines=[]):
        """Add (and commit) a comment for the given file and lines."""
        if filename and filename not in self.target[self.node].files():
            raise FileNotInChangeset(filename)
        
        comment = ReviewComment(self.ui.username(), datetime.utcnow(),
            self.node, filename, lines, message)
        comment.commit(self.ui, self.repo)
    
    def full_diffs(self, filenames=None, opts={}):
        """Return diffs of the given files."""
        
        target_files = self.target[self.node].files()
        if not filenames:
            filenames = target_files
        else:
            filenames = filter(lambda f: f in target_files, filenames)
        
        opts['unified'] = '100000'
        node2 = self.node
        node1 = self.target[node2].parents()[0].node()
        
        diffs = {}
        for filename in filenames:
            m = cmdutil.matchfiles(self.target, [filename])
            d = patch.diff(self.target, node1, node2, match=m,
                opts=patch.diffopts(self.ui, opts))
            
            # patch.diff will give us back a generator with two items
            # the first is the diff header, which we don't care about
            d.next()
            
            # the second is the diff's contents, which is what we want
            diffs[filename] = d.next()
        
        return diffs
    

class _ReviewObject(object):
    """Some kind of object."""
    def __init__(self, container, commit_message, delete_message=None):
        self.container = container
        self.commit_message = commit_message
        self.delete_message = delete_message
    
    def commit(self, ui, repo):
        """Write and commit this object to the given repo."""
        
        path = os.path.join(repo.root, self.node, self.container)
        if not os.path.exists(path):
            os.mkdir(path)
        
        data = self.render_data()
        filename = sha1(data).hexdigest()
        objectpath = os.path.join(path, filename)
        
        with open(objectpath, 'w') as objectfile:
            objectfile.write(data)
        
        cmdutil.commit(ui, repo, _commitfunc, [objectpath],
            { 'message': self.commit_message % self.node, 'addremove': True, })
    
    def delete(self, ui, repo):
        """Delete and commit this object in the given repo."""
        
        if not self.delete_message:
            raise CannotDeleteObject
        
        data = self.render_data()
        filename = sha1(data).hexdigest()
        objectpath = os.path.join(repo.root, self.node, self.container, filename)
        
        os.remove(objectpath)
        
        cmdutil.commit(ui, repo, _commitfunc, [objectpath],
            { 'message': self.delete_message % self.node, 'addremove': True, })
    

class ReviewComment(_ReviewObject):
    """A single review comment."""
    def __init__(self, author, datetime, node, filename, lines, message, **extra):
        super(ReviewComment, self).__init__(
            container='comments', commit_message=messages.COMMIT_COMMENT,
        )
        self.author = author
        self.datetime = datetime
        self.node = node
        self.filename = filename
        self.lines = lines
        self.message = message
    
    def render_data(self):
        datetime = str(self.datetime)
        lines = ','.join(self.lines)
        return templates.COMMENT_FILE_TEMPLATE % ( self.author, datetime,
            self.node, self.filename, lines, self.message )
    
    def __str__(self):
        return '\n'.join(map(str, [
            self.author,
            self.datetime,
            self.node,
            self.filename,
            self.lines,
            self.message,
            '\n',
        ]))
    

class ReviewSignoff(_ReviewObject):
    """A single review signoff."""
    def __init__(self, author, datetime, node, opinion, message, **extra):
        super(ReviewSignoff, self).__init__(
            container='signoffs', commit_message=messages.COMMIT_SIGNOFF,
            delete_message=messages.DELETE_SIGNOFF,
        )
        self.author = author
        self.datetime = datetime
        self.node = node
        self.opinion = opinion
        self.message = message
    
    def render_data(self):
        datetime = str(self.datetime)
        return templates.SIGNOFF_FILE_TEMPLATE % ( self.author, datetime,
            self.node, self.opinion, self.message )