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371
371
                tree.lock_read()
372
372
        new_tree.lock_read()
373
373
        try:
374
 
            return _show_diff_trees(old_tree, new_tree, to_file,
375
 
                                    specific_files, external_diff_options,
376
 
                                    old_label=old_label, new_label=new_label,
377
 
                                    extra_trees=extra_trees,
378
 
                                    path_encoding=path_encoding)
 
374
            differ = DiffTree.from_trees_options(old_tree, new_tree, to_file,
 
375
                                                   path_encoding,
 
376
                                                   external_diff_options,
 
377
                                                   old_label, new_label)
 
378
            return differ.show_diff(specific_files, extra_trees)
379
379
        finally:
380
380
            new_tree.unlock()
381
381
            if extra_trees is not None:
385
385
        old_tree.unlock()
386
386
 
387
387
 
388
 
def _show_diff_trees(old_tree, new_tree, to_file,
389
 
                     specific_files, external_diff_options, path_encoding,
390
 
                     old_label='a/', new_label='b/', extra_trees=None):
391
 
 
392
 
    # GNU Patch uses the epoch date to detect files that are being added
393
 
    # or removed in a diff.
394
 
    EPOCH_DATE = '1970-01-01 00:00:00 +0000'
395
 
 
396
 
    # TODO: Generation of pseudo-diffs for added/deleted files could
397
 
    # be usefully made into a much faster special case.
398
 
 
399
 
    if external_diff_options:
400
 
        assert isinstance(external_diff_options, basestring)
401
 
        opts = external_diff_options.split()
402
 
        def diff_file(olab, olines, nlab, nlines, to_file):
403
 
            external_diff(olab, olines, nlab, nlines, to_file, opts)
404
 
    else:
405
 
        diff_file = internal_diff
406
 
    
407
 
    delta = new_tree.changes_from(old_tree,
408
 
        specific_files=specific_files,
409
 
        extra_trees=extra_trees, require_versioned=True)
410
 
 
411
 
    has_changes = 0
412
 
    for path, file_id, kind in delta.removed:
413
 
        has_changes = 1
414
 
        path_encoded = path.encode(path_encoding, "replace")
415
 
        to_file.write("=== removed %s '%s'\n" % (kind, path_encoded))
416
 
        old_name = '%s%s\t%s' % (old_label, path,
417
 
                                 _patch_header_date(old_tree, file_id, path))
418
 
        new_name = '%s%s\t%s' % (new_label, path, EPOCH_DATE)
419
 
        old_tree.inventory[file_id].diff(diff_file, old_name, old_tree,
420
 
                                         new_name, None, None, to_file)
421
 
    for path, file_id, kind in delta.added:
422
 
        has_changes = 1
423
 
        path_encoded = path.encode(path_encoding, "replace")
424
 
        to_file.write("=== added %s '%s'\n" % (kind, path_encoded))
425
 
        old_name = '%s%s\t%s' % (old_label, path, EPOCH_DATE)
426
 
        new_name = '%s%s\t%s' % (new_label, path,
427
 
                                 _patch_header_date(new_tree, file_id, path))
428
 
        new_tree.inventory[file_id].diff(diff_file, new_name, new_tree,
429
 
                                         old_name, None, None, to_file, 
430
 
                                         reverse=True)
431
 
    for (old_path, new_path, file_id, kind,
432
 
         text_modified, meta_modified) in delta.renamed:
433
 
        has_changes = 1
434
 
        prop_str = get_prop_change(meta_modified)
435
 
        oldpath_encoded = old_path.encode(path_encoding, "replace")
436
 
        newpath_encoded = new_path.encode(path_encoding, "replace")
437
 
        to_file.write("=== renamed %s '%s' => '%s'%s\n" % (kind,
438
 
                            oldpath_encoded, newpath_encoded, prop_str))
439
 
        old_name = '%s%s\t%s' % (old_label, old_path,
440
 
                                 _patch_header_date(old_tree, file_id,
441
 
                                                    old_path))
442
 
        new_name = '%s%s\t%s' % (new_label, new_path,
443
 
                                 _patch_header_date(new_tree, file_id,
444
 
                                                    new_path))
445
 
        _maybe_diff_file_or_symlink(old_name, old_tree, file_id,
446
 
                                    new_name, new_tree,
447
 
                                    text_modified, kind, to_file, diff_file)
448
 
    for path, file_id, kind, text_modified, meta_modified in delta.modified:
449
 
        has_changes = 1
450
 
        prop_str = get_prop_change(meta_modified)
451
 
        path_encoded = path.encode(path_encoding, "replace")
452
 
        to_file.write("=== modified %s '%s'%s\n" % (kind,
453
 
                            path_encoded, prop_str))
454
 
        # The file may be in a different location in the old tree (because
455
 
        # the containing dir was renamed, but the file itself was not)
456
 
        old_path = old_tree.id2path(file_id)
457
 
        old_name = '%s%s\t%s' % (old_label, old_path,
458
 
                                 _patch_header_date(old_tree, file_id, old_path))
459
 
        new_name = '%s%s\t%s' % (new_label, path,
460
 
                                 _patch_header_date(new_tree, file_id, path))
461
 
        if text_modified:
462
 
            _maybe_diff_file_or_symlink(old_name, old_tree, file_id,
463
 
                                        new_name, new_tree,
464
 
                                        True, kind, to_file, diff_file)
465
 
 
466
 
    return has_changes
467
 
 
468
 
 
469
388
def _patch_header_date(tree, file_id, path):
470
389
    """Returns a timestamp suitable for use in a patch header."""
471
390
    mtime = tree.get_file_mtime(file_id, path)
501
420
        return  ""
502
421
 
503
422
 
504
 
def _maybe_diff_file_or_symlink(old_path, old_tree, file_id,
505
 
                                new_path, new_tree, text_modified,
506
 
                                kind, to_file, diff_file):
507
 
    if text_modified:
508
 
        new_entry = new_tree.inventory[file_id]
509
 
        old_tree.inventory[file_id].diff(diff_file,
510
 
                                         old_path, old_tree,
511
 
                                         new_path, new_entry, 
512
 
                                         new_tree, to_file)
 
423
class DiffPath(object):
 
424
    """Base type for command object that compare files"""
 
425
 
 
426
    # The type or contents of the file were unsuitable for diffing
 
427
    CANNOT_DIFF = 'CANNOT_DIFF'
 
428
    # The file has changed in a semantic way
 
429
    CHANGED = 'CHANGED'
 
430
    # The file content may have changed, but there is no semantic change
 
431
    UNCHANGED = 'UNCHANGED'
 
432
 
 
433
    def __init__(self, old_tree, new_tree, to_file, path_encoding='utf-8'):
 
434
        """Constructor.
 
435
 
 
436
        :param old_tree: The tree to show as the old tree in the comparison
 
437
        :param new_tree: The tree to show as new in the comparison
 
438
        :param to_file: The file to write comparison data to
 
439
        :param path_encoding: The character encoding to write paths in
 
440
        """
 
441
        self.old_tree = old_tree
 
442
        self.new_tree = new_tree
 
443
        self.to_file = to_file
 
444
        self.path_encoding = path_encoding
 
445
 
 
446
    @classmethod
 
447
    def from_diff_tree(klass, diff_tree):
 
448
        return klass(diff_tree.old_tree, diff_tree.new_tree,
 
449
                     diff_tree.to_file, diff_tree.path_encoding)
 
450
 
 
451
    @staticmethod
 
452
    def _diff_many(differs, file_id, old_path, new_path, old_kind, new_kind):
 
453
        for file_differ in differs:
 
454
            result = file_differ.diff(file_id, old_path, new_path, old_kind,
 
455
                                      new_kind)
 
456
            if result is not DiffPath.CANNOT_DIFF:
 
457
                return result
 
458
        else:
 
459
            return DiffPath.CANNOT_DIFF
 
460
 
 
461
 
 
462
class DiffKindChange(object):
 
463
    """Special differ for file kind changes.
 
464
 
 
465
    Represents kind change as deletion + creation.  Uses the other differs
 
466
    to do this.
 
467
    """
 
468
    def __init__(self, differs):
 
469
        self.differs = differs
 
470
 
 
471
    @classmethod
 
472
    def from_diff_tree(klass, diff_tree):
 
473
        return klass(diff_tree.differs)
 
474
 
 
475
    def diff(self, file_id, old_path, new_path, old_kind, new_kind):
 
476
        """Perform comparison
 
477
 
 
478
        :param file_id: The file_id of the file to compare
 
479
        :param old_path: Path of the file in the old tree
 
480
        :param new_path: Path of the file in the new tree
 
481
        :param old_kind: Old file-kind of the file
 
482
        :param new_kind: New file-kind of the file
 
483
        """
 
484
        if None in (old_kind, new_kind):
 
485
            return DiffPath.CANNOT_DIFF
 
486
        result = DiffPath._diff_many(self.differs, file_id, old_path,
 
487
                                       new_path, old_kind, None)
 
488
        if result is DiffPath.CANNOT_DIFF:
 
489
            return result
 
490
        return DiffPath._diff_many(self.differs, file_id, old_path, new_path,
 
491
                                     None, new_kind)
 
492
 
 
493
 
 
494
class DiffDirectory(DiffPath):
 
495
 
 
496
    def diff(self, file_id, old_path, new_path, old_kind, new_kind):
 
497
        """Perform comparison between two directories.  (dummy)
 
498
 
 
499
        """
 
500
        if 'directory' not in (old_kind, new_kind):
 
501
            return self.CANNOT_DIFF
 
502
        if old_kind not in ('directory', None):
 
503
            return self.CANNOT_DIFF
 
504
        if new_kind not in ('directory', None):
 
505
            return self.CANNOT_DIFF
 
506
        return self.CHANGED
 
507
 
 
508
 
 
509
class DiffSymlink(DiffPath):
 
510
 
 
511
    def diff(self, file_id, old_path, new_path, old_kind, new_kind):
 
512
        """Perform comparison between two symlinks
 
513
 
 
514
        :param file_id: The file_id of the file to compare
 
515
        :param old_path: Path of the file in the old tree
 
516
        :param new_path: Path of the file in the new tree
 
517
        :param old_kind: Old file-kind of the file
 
518
        :param new_kind: New file-kind of the file
 
519
        """
 
520
        if 'symlink' not in (old_kind, new_kind):
 
521
            return self.CANNOT_DIFF
 
522
        if old_kind == 'symlink':
 
523
            old_target = self.old_tree.get_symlink_target(file_id)
 
524
        elif old_kind is None:
 
525
            old_target = None
 
526
        else:
 
527
            return self.CANNOT_DIFF
 
528
        if new_kind == 'symlink':
 
529
            new_target = self.new_tree.get_symlink_target(file_id)
 
530
        elif new_kind is None:
 
531
            new_target = None
 
532
        else:
 
533
            return self.CANNOT_DIFF
 
534
        return self.diff_symlink(old_target, new_target)
 
535
 
 
536
    def diff_symlink(self, old_target, new_target):
 
537
        if old_target is None:
 
538
            self.to_file.write('=== target is %r\n' % new_target)
 
539
        elif new_target is None:
 
540
            self.to_file.write('=== target was %r\n' % old_target)
 
541
        else:
 
542
            self.to_file.write('=== target changed %r => %r\n' %
 
543
                              (old_target, new_target))
 
544
        return self.CHANGED
 
545
 
 
546
 
 
547
class DiffText(DiffPath):
 
548
 
 
549
    # GNU Patch uses the epoch date to detect files that are being added
 
550
    # or removed in a diff.
 
551
    EPOCH_DATE = '1970-01-01 00:00:00 +0000'
 
552
 
 
553
    def __init__(self, old_tree, new_tree, to_file, path_encoding='utf-8',
 
554
                 old_label='', new_label='', text_differ=internal_diff):
 
555
        DiffPath.__init__(self, old_tree, new_tree, to_file, path_encoding)
 
556
        self.text_differ = text_differ
 
557
        self.old_label = old_label
 
558
        self.new_label = new_label
 
559
        self.path_encoding = path_encoding
 
560
 
 
561
    def diff(self, file_id, old_path, new_path, old_kind, new_kind):
 
562
        """Compare two files in unified diff format
 
563
 
 
564
        :param file_id: The file_id of the file to compare
 
565
        :param old_path: Path of the file in the old tree
 
566
        :param new_path: Path of the file in the new tree
 
567
        :param old_kind: Old file-kind of the file
 
568
        :param new_kind: New file-kind of the file
 
569
        """
 
570
        if 'file' not in (old_kind, new_kind):
 
571
            return self.CANNOT_DIFF
 
572
        from_file_id = to_file_id = file_id
 
573
        if old_kind == 'file':
 
574
            old_date = _patch_header_date(self.old_tree, file_id, old_path)
 
575
        elif old_kind is None:
 
576
            old_date = self.EPOCH_DATE
 
577
            from_file_id = None
 
578
        else:
 
579
            return self.CANNOT_DIFF
 
580
        if new_kind == 'file':
 
581
            new_date = _patch_header_date(self.new_tree, file_id, new_path)
 
582
        elif new_kind is None:
 
583
            new_date = self.EPOCH_DATE
 
584
            to_file_id = None
 
585
        else:
 
586
            return self.CANNOT_DIFF
 
587
        from_label = '%s%s\t%s' % (self.old_label, old_path, old_date)
 
588
        to_label = '%s%s\t%s' % (self.new_label, new_path, new_date)
 
589
        return self.diff_text(from_file_id, to_file_id, from_label, to_label)
 
590
 
 
591
    def diff_text(self, from_file_id, to_file_id, from_label, to_label):
 
592
        """Diff the content of given files in two trees
 
593
 
 
594
        :param from_file_id: The id of the file in the from tree.  If None,
 
595
            the file is not present in the from tree.
 
596
        :param to_file_id: The id of the file in the to tree.  This may refer
 
597
            to a different file from from_file_id.  If None,
 
598
            the file is not present in the to tree.
 
599
        """
 
600
        def _get_text(tree, file_id):
 
601
            if file_id is not None:
 
602
                return tree.get_file(file_id).readlines()
 
603
            else:
 
604
                return []
 
605
        try:
 
606
            from_text = _get_text(self.old_tree, from_file_id)
 
607
            to_text = _get_text(self.new_tree, to_file_id)
 
608
            self.text_differ(from_label, from_text, to_label, to_text,
 
609
                             self.to_file)
 
610
        except errors.BinaryFile:
 
611
            self.to_file.write(
 
612
                  ("Binary files %s and %s differ\n" %
 
613
                  (from_label, to_label)).encode(self.path_encoding))
 
614
        return self.CHANGED
 
615
 
 
616
 
 
617
class DiffTree(object):
 
618
    """Provides textual representations of the difference between two trees.
 
619
 
 
620
    A DiffTree examines two trees and where a file-id has altered
 
621
    between them, generates a textual representation of the difference.
 
622
    DiffTree uses a sequence of DiffPath objects which are each
 
623
    given the opportunity to handle a given altered fileid. The list
 
624
    of DiffPath objects can be extended globally by appending to
 
625
    DiffTree.diff_factories, or for a specific diff operation by
 
626
    supplying the extra_factories option to the appropriate method.
 
627
    """
 
628
 
 
629
    # list of factories that can provide instances of DiffPath objects
 
630
    # may be extended by plugins.
 
631
    diff_factories = [DiffSymlink.from_diff_tree,
 
632
                      DiffDirectory.from_diff_tree]
 
633
 
 
634
    def __init__(self, old_tree, new_tree, to_file, path_encoding='utf-8',
 
635
                 diff_text=None, extra_factories=None):
 
636
        """Constructor
 
637
 
 
638
        :param old_tree: Tree to show as old in the comparison
 
639
        :param new_tree: Tree to show as new in the comparison
 
640
        :param to_file: File to write comparision to
 
641
        :param path_encoding: Character encoding to write paths in
 
642
        :param diff_text: DiffPath-type object to use as a last resort for
 
643
            diffing text files.
 
644
        :param extra_factories: Factories of DiffPaths to try before any other
 
645
            DiffPaths"""
 
646
        if diff_text is None:
 
647
            diff_text = DiffText(old_tree, new_tree, to_file, path_encoding,
 
648
                                 '', '',  internal_diff)
 
649
        self.old_tree = old_tree
 
650
        self.new_tree = new_tree
 
651
        self.to_file = to_file
 
652
        self.path_encoding = path_encoding
 
653
        self.differs = []
 
654
        if extra_factories is not None:
 
655
            self.differs.extend(f(self) for f in extra_factories)
 
656
        self.differs.extend(f(self) for f in self.diff_factories)
 
657
        self.differs.extend([diff_text, DiffKindChange.from_diff_tree(self)])
 
658
 
 
659
    @classmethod
 
660
    def from_trees_options(klass, old_tree, new_tree, to_file,
 
661
                           path_encoding, external_diff_options, old_label,
 
662
                           new_label):
 
663
        """Factory for producing a DiffTree.
 
664
 
 
665
        Designed to accept options used by show_diff_trees.
 
666
        :param old_tree: The tree to show as old in the comparison
 
667
        :param new_tree: The tree to show as new in the comparison
 
668
        :param to_file: File to write comparisons to
 
669
        :param path_encoding: Character encoding to use for writing paths
 
670
        :param external_diff_options: If supplied, use the installed diff
 
671
            binary to perform file comparison, using supplied options.
 
672
        :param old_label: Prefix to use for old file labels
 
673
        :param new_label: Prefix to use for new file labels
 
674
        """
 
675
        if external_diff_options:
 
676
            assert isinstance(external_diff_options, basestring)
 
677
            opts = external_diff_options.split()
 
678
            def diff_file(olab, olines, nlab, nlines, to_file):
 
679
                external_diff(olab, olines, nlab, nlines, to_file, opts)
 
680
        else:
 
681
            diff_file = internal_diff
 
682
        diff_text = DiffText(old_tree, new_tree, to_file, path_encoding,
 
683
                             old_label, new_label, diff_file)
 
684
        return klass(old_tree, new_tree, to_file, path_encoding, diff_text)
 
685
 
 
686
    def show_diff(self, specific_files, extra_trees=None):
 
687
        """Write tree diff to self.to_file
 
688
 
 
689
        :param sepecific_files: the specific files to compare (recursive)
 
690
        :param extra_trees: extra trees to use for mapping paths to file_ids
 
691
        """
 
692
        # TODO: Generation of pseudo-diffs for added/deleted files could
 
693
        # be usefully made into a much faster special case.
 
694
 
 
695
        delta = self.new_tree.changes_from(self.old_tree,
 
696
            specific_files=specific_files,
 
697
            extra_trees=extra_trees, require_versioned=True)
 
698
 
 
699
        has_changes = 0
 
700
        for path, file_id, kind in delta.removed:
 
701
            has_changes = 1
 
702
            path_encoded = path.encode(self.path_encoding, "replace")
 
703
            self.to_file.write("=== removed %s '%s'\n" % (kind, path_encoded))
 
704
            self.diff(file_id, path, path)
 
705
 
 
706
        for path, file_id, kind in delta.added:
 
707
            has_changes = 1
 
708
            path_encoded = path.encode(self.path_encoding, "replace")
 
709
            self.to_file.write("=== added %s '%s'\n" % (kind, path_encoded))
 
710
            self.diff(file_id, path, path)
 
711
        for (old_path, new_path, file_id, kind,
 
712
             text_modified, meta_modified) in delta.renamed:
 
713
            has_changes = 1
 
714
            prop_str = get_prop_change(meta_modified)
 
715
            oldpath_encoded = old_path.encode(self.path_encoding, "replace")
 
716
            newpath_encoded = new_path.encode(self.path_encoding, "replace")
 
717
            self.to_file.write("=== renamed %s '%s' => '%s'%s\n" % (kind,
 
718
                                oldpath_encoded, newpath_encoded, prop_str))
 
719
            if text_modified:
 
720
                self.diff(file_id, old_path, new_path)
 
721
        for path, file_id, kind, text_modified, meta_modified in\
 
722
            delta.modified:
 
723
            has_changes = 1
 
724
            prop_str = get_prop_change(meta_modified)
 
725
            path_encoded = path.encode(self.path_encoding, "replace")
 
726
            self.to_file.write("=== modified %s '%s'%s\n" % (kind,
 
727
                                path_encoded, prop_str))
 
728
            # The file may be in a different location in the old tree (because
 
729
            # the containing dir was renamed, but the file itself was not)
 
730
            if text_modified:
 
731
                old_path = self.old_tree.id2path(file_id)
 
732
                self.diff(file_id, old_path, path)
 
733
        return has_changes
 
734
 
 
735
    def diff(self, file_id, old_path, new_path):
 
736
        """Perform a diff of a single file
 
737
 
 
738
        :param file_id: file-id of the file
 
739
        :param old_path: The path of the file in the old tree
 
740
        :param new_path: The path of the file in the new tree
 
741
        """
 
742
        try:
 
743
            old_kind = self.old_tree.kind(file_id)
 
744
        except errors.NoSuchId:
 
745
            old_kind = None
 
746
        try:
 
747
            new_kind = self.new_tree.kind(file_id)
 
748
        except errors.NoSuchId:
 
749
            new_kind = None
 
750
 
 
751
        result = DiffPath._diff_many(self.differs, file_id, old_path,
 
752
                                       new_path, old_kind, new_kind)
 
753
        if result is DiffPath.CANNOT_DIFF:
 
754
            error_path = new_path
 
755
            if error_path is None:
 
756
                error_path = old_path
 
757
            raise errors.NoDiffFound(error_path)