Provide a feature not present into difflib, which is generate a colored diff

 from a diff file/string. This code is original form ERP5Subversion and was moved 
 to here for be used in general ERP5. 

 XXX The organisation of DiffUtils should be reviewed and reorganised if needed. 
 ie.: Move behaviour to a tool.



git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@32272 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Type/DiffUtils.py

+##############################################################################
+#
+# Copyright (c) 2005 Nexedi SARL and Contributors. All Rights Reserved.
+#                    Yoshinori Okuji <yo@nexedi.com>
+#                    Christophe Dumez <christophe@nexedi.com>
+#
+# WARNING: This program as such is intended to be used by professional
+# programmers who take the whole responsability of assessing all potential
+# consequences resulting from its eventual inadequacies and bugs
+# End users who are looking for a ready-to-use solution with commercial
+# garantees and support are strongly adviced to contract a Free Software
+# Service Company
+#
+# This program is Free Software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+#
+##############################################################################
+
+"""
+ Provide a feature not present into difflib, which is generate a colored diff
+ from a diff file/string.
+
+ This code is original form ERP5Subversion and was moved to here for be used in
+ general ERP5. 
+
+ XXX The organisation of DiffUtils should be reviewed and reorganised in a tool
+ if a general tool want to be provided.
+"""
+import os, re
+from xml.sax.saxutils import escape
+
+NBSP = '&nbsp;'
+NBSP_TAB = NBSP*8
+
+class DiffFile:
+  """
+  # Members :
+   - path : path of the modified file
+   - children : sub codes modified
+   - old_revision
+   - new_revision
+  """
+
+  def __init__(self, raw_diff):
+    if '@@' not in raw_diff:
+      self.binary = True
+      return
+    else:
+      self.binary = False
+    self.header = raw_diff.split('@@')[0][:-1]
+    # Getting file path in header
+    self.path = self.header.split('====')[0][:-1].strip()
+    # Getting revisions in header
+    for line in self.header.splitlines():
+      if line.startswith('--- '):
+        tmp = re.search('\\([^)]+\\)$', line)
+        self.old_revision = tmp.string[tmp.start():tmp.end()][1:-1].strip()
+      if line.startswith('+++ '):
+        tmp = re.search('\\([^)]+\\)$', line)
+        self.new_revision = tmp.string[tmp.start():tmp.end()][1:-1].strip()
+    # Splitting the body from the header
+    self.body = os.linesep.join(raw_diff.strip().splitlines()[4:])
+    # Now splitting modifications
+    self.children = []
+    first = True
+    tmp = []
+    for line in self.body.splitlines():
+      if line:
+        if line.startswith('@@') and not first:
+          self.children.append(CodeBlock(os.linesep.join(tmp)))
+          tmp = [line, ]
+        else:
+          first = False
+          tmp.append(line)
+    self.children.append(CodeBlock(os.linesep.join(tmp)))
+    
+  def toHTML(self):
+    """ return HTML diff
+    """
+    # Adding header of the table
+    if self.binary:
+      return '<b>Folder or binary file or just no changes!</b><br/><br/><br/>'
+    
+    html_list = []
+    html_list.append('''
+    <table style="text-align: left; width: 100%%; border: 0;" cellpadding="0" cellspacing="0">
+  <tbody>
+    <tr>
+      <td style="background-color: grey; text-align: center; font-weight: bold;">%s</td>
+      <td style="background-color: black; width: 2px;"></td>
+      <td style="background-color: grey; text-align: center; font-weight: bold;">%s</td>
+    </tr>''' % (self.old_revision, self.new_revision))
+    header_color = 'grey'
+    child_html_text = '''<tr><td style="background-color: %(headcolor)s">
+    &nbsp;</td><td style="background-color: black; width: 2px;"></td>
+    <td style="background-color: %(headcolor)s">&nbsp;</td></tr><tr>
+    <td style="background-color: rgb(68, 132, 255);font-weight: bold;">Line %(oldline)s</td>
+    <td style="background-color: black; width: 2px;"></td>
+    <td style="background-color: rgb(68, 132, 255);font-weight: bold;">Line %(newline)s</td>
+    </tr>'''
+    for child in self.children:
+      # Adding line number of the modification
+      html_list.append( child_html_text % {'headcolor':header_color, 'oldline':child.old_line, 'newline':child.new_line} )
+      header_color = 'white'
+      # Adding diff of the modification
+      old_code_list = child.getOldCodeList()
+      new_code_list = child.getNewCodeList()
+      i = 0
+      for old_line_tuple in old_code_list:
+        new_line_tuple = new_code_list[i]
+        new_line = new_line_tuple[0] or ' '
+        old_line = old_line_tuple[0] or ' '
+        i += 1
+        html_list.append( '''<tr>
+        <td style="background-color: %s">%s</td>
+        <td style="background-color: black; width: 2px;"></td>
+        <td style="background-color: %s">%s</td>
+        </tr>'''%(old_line_tuple[1],
+        escape(old_line).replace(' ', NBSP).replace('\t', NBSP_TAB),
+        new_line_tuple[1],
+        escape(new_line).replace(' ', NBSP).replace('\t', NBSP_TAB))
+        )
+    html_list.append('''</tbody></table><br/>''')
+    return '\n'.join(html_list)
+
+class CodeBlock:
+  """
+   A code block contains several SubCodeBlocks
+   Members :
+   - old_line : line in old code (before modif)
+   - new line : line in new code (after modif)
+  
+   Methods :
+   - getOldCodeList() : return code before modif
+   - getNewCodeList() : return code after modif
+   Note: the code returned is a list of tuples (code line, background color)
+  """
+
+  def __init__(self, raw_diff):
+    # Splitting body and header
+    self.body = os.linesep.join(raw_diff.splitlines()[1:])
+    self.header = raw_diff.splitlines()[0]
+    # Getting modifications lines
+    tmp = re.search('^@@ -\d+', self.header)
+    self.old_line = tmp.string[tmp.start():tmp.end()][4:]
+    tmp = re.search('\+\d+', self.header)
+    self.new_line = tmp.string[tmp.start():tmp.end()][1:]
+    # Splitting modifications in SubCodeBlocks
+    in_modif = False
+    self.children = []
+    tmp = []
+    for line in self.body.splitlines():
+      if line:
+        if (line.startswith('+') or line.startswith('-')):
+          if in_modif:
+            tmp.append(line)
+          else:
+            self.children.append(SubCodeBlock(os.linesep.join(tmp)))
+            tmp = [line, ]
+            in_modif = True
+        else:
+          if in_modif:
+            self.children.append(SubCodeBlock(os.linesep.join(tmp)))
+            tmp = [line, ]
+            in_modif = False
+          else:
+            tmp.append(line)
+    self.children.append(SubCodeBlock(os.linesep.join(tmp)))
+    
+  def getOldCodeList(self):
+    """ Return code before modification
+    """
+    tmp = []
+    for child in self.children:
+      tmp.extend(child.getOldCodeList())
+    return tmp
+    
+  def getNewCodeList(self):
+    """ Return code after modification
+    """
+    tmp = []
+    for child in self.children:
+      tmp.extend(child.getNewCodeList())
+    return tmp
+    
+class SubCodeBlock:
+  """ a SubCodeBlock contain 0 or 1 modification (not more)
+  """
+  def __init__(self, code):
+    self.body = code
+    self.modification = self._getModif()
+    self.old_code_length = self._getOldCodeLength()
+    self.new_code_length = self._getNewCodeLength()
+    # Choosing background color
+    if self.modification == 'none':
+      self.color = 'white'
+    elif self.modification == 'change':
+      self.color = 'rgb(253, 228, 6);'#light orange
+    elif self.modification == 'deletion':
+      self.color = 'rgb(253, 117, 74);'#light red
+    else: # addition
+      self.color = 'rgb(83, 253, 74);'#light green
+    
+  def _getModif(self):
+    """ Return type of modification :
+        addition, deletion, none
+    """
+    nb_plus = 0
+    nb_minus = 0
+    for line in self.body.splitlines():
+      if line.startswith("-"):
+        nb_minus -= 1
+      elif line.startswith("+"):
+        nb_plus += 1
+    if (nb_plus == 0 and nb_minus == 0):
+      return 'none'
+    if (nb_minus == 0):
+      return 'addition'
+    if (nb_plus == 0):
+      return 'deletion'
+    return 'change'
+      
+  def _getOldCodeLength(self):
+    """ Private function to return old code length
+    """
+    nb_lines = 0
+    for line in self.body.splitlines():
+      if not line.startswith("+"):
+        nb_lines += 1
+    return nb_lines
+      
+  def _getNewCodeLength(self):
+    """ Private function to return new code length
+    """
+    nb_lines = 0
+    for line in self.body.splitlines():
+      if not line.startswith("-"):
+        nb_lines += 1
+    return nb_lines
+  
+  def getOldCodeList(self):
+    """ Return code before modification
+    """
+    if self.modification == 'none':
+      old_code = [(x, 'white') for x in self.body.splitlines()]
+    elif self.modification == 'change':
+      old_code = [self._getOldCodeList(x) for x in self.body.splitlines() \
+      if self._getOldCodeList(x)[0]]
+      # we want old_code_list and new_code_list to have the same length
+      if(self.old_code_length < self.new_code_length):
+        filling = [(None, self.color)] * (self.new_code_length - \
+        self.old_code_length)
+        old_code.extend(filling)
+    else: # deletion or addition
+      old_code = [self._getOldCodeList(x) for x in self.body.splitlines()]
+    return old_code
+  
+  def _getOldCodeList(self, line):
+    """ Private function to return code before modification
+    """
+    if line.startswith('+'):
+      return (None, self.color)
+    if line.startswith('-'):
+      return (' ' + line[1:], self.color)
+    return (line, self.color)
+  
+  def getNewCodeList(self):
+    """ Return code after modification
+    """
+    if self.modification == 'none':
+      new_code = [(x, 'white') for x in self.body.splitlines()]
+    elif self.modification == 'change':
+      new_code = [self._getNewCodeList(x) for x in self.body.splitlines() \
+      if self._getNewCodeList(x)[0]]
+      # we want old_code_list and new_code_list to have the same length
+      if(self.new_code_length < self.old_code_length):
+        filling = [(None, self.color)] * (self.old_code_length - \
+        self.new_code_length)
+        new_code.extend(filling)
+    else: # deletion or addition
+      new_code = [self._getNewCodeList(x) for x in self.body.splitlines()]
+    return new_code
+  
+  def _getNewCodeList(self, line):
+    """ Private function to return code after modification
+    """
+    if line.startswith('-'):
+      return (None, self.color)
+    if line.startswith('+'):
+      return (' ' + line[1:], self.color)
+    return (line, self.color)