Re-land: Change actions.txt to actions.xml

tools/metrics/histograms/pretty_print.py

 #!/usr/bin/env python
 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Pretty-prints the histograms.xml file, alphabetizing tags, wrapping text
 at 80 chars, enforcing standard attribute ordering, and standardizing
 indentation.
 
 This is quite a bit more complicated than just calling tree.toprettyxml();
 we need additional customization, like special attribute ordering in tags
 and wrapping text nodes, so we implement our own full custom XML pretty-printer.
 """
 
 from __future__ import with_statement
 
-import diffutil
-import json
 import logging
 import os
 import shutil
 import sys
-import textwrap
 import xml.dom.minidom
 
+import print_style
+
 sys.path.insert(1, os.path.join(sys.path[0], '..', '..', 'python'))
 from google import path_utils
 
-WRAP_COLUMN = 80
-
-# Desired order for tag attributes; attributes listed here will appear first,
-# and in the same order as in these lists.
-# { tag_name: [attribute_name, ...] }
-ATTRIBUTE_ORDER = {
-  'enum': ['name', 'type'],
-  'histogram': ['name', 'enum', 'units'],
-  'int': ['value', 'label'],
-  'fieldtrial': ['name', 'separator', 'ordering'],
-  'group': ['name', 'label'],
-  'affected-histogram': ['name'],
-  'with-group': ['name'],
-}
-
-# Tag names for top-level nodes whose children we don't want to indent.
-TAGS_THAT_DONT_INDENT = [
-  'histogram-configuration',
-  'histograms',
-  'fieldtrials',
-  'enums'
-]
-
-# Extra vertical spacing rules for special tag names.
-# {tag_name: (newlines_after_open, newlines_before_close, newlines_after_close)}
-TAGS_THAT_HAVE_EXTRA_NEWLINE = {
-  'histogram-configuration': (2, 1, 1),
-  'histograms': (2, 1, 1),
-  'fieldtrials': (2, 1, 1),
-  'enums': (2, 1, 1),
-  'histogram': (1, 1, 1),
-  'enum': (1, 1, 1),
-  'fieldtrial': (1, 1, 1),
-}
-
-# Tags that we allow to be squished into a single line for brevity.
-TAGS_THAT_ALLOW_SINGLE_LINE = [
-  'summary',
-  'int',
-]
+# Import the metrics/common module.
+sys.path.append(os.path.join(os.path.dirname(__file__), '..', 'common'))
+import diff_util
 
 # Tags whose children we want to alphabetize. The key is the parent tag name,
 # and the value is a pair of the tag name of the children we want to sort,
 # and a key function that maps each child node to the desired sort key.
 ALPHABETIZATION_RULES = {
   'histograms': ('histogram', lambda n: n.attributes['name'].value.lower()),
   'enums': ('enum', lambda n: n.attributes['name'].value.lower()),
   'enum': ('int', lambda n: int(n.attributes['value'].value)),
   'fieldtrials': ('fieldtrial', lambda n: n.attributes['name'].value.lower()),
   'fieldtrial': ('affected-histogram',
                  lambda n: n.attributes['name'].value.lower()),
 }
 
 
 class Error(Exception):
   pass
 
 
-def LastLineLength(s):
-  """Returns the length of the last line in s.
-
-  Args:
-    s: A multi-line string, including newlines.
-
-  Returns:
-    The length of the last line in s, in characters.
-  """
-  if s.rfind('\n') == -1: return len(s)
-  return len(s) - s.rfind('\n') - len('\n')
-
-
-def XmlEscape(s):
-  """XML-escapes the given string, replacing magic characters (&<>") with their
-  escaped equivalents."""
-  s = s.replace("&", "&amp;").replace("<", "&lt;")
-  s = s.replace("\"", "&quot;").replace(">", "&gt;")
-  return s
-
-
-def PrettyPrintNode(node, indent=0):
-  """Pretty-prints the given XML node at the given indent level.
-
-  Args:
-    node: The minidom node to pretty-print.
-    indent: The current indent level.
-
-  Returns:
-    The pretty-printed string (including embedded newlines).
-
-  Raises:
-    Error if the XML has unknown tags or attributes.
-  """
-  # Handle the top-level document node.
-  if node.nodeType == xml.dom.minidom.Node.DOCUMENT_NODE:
-    return '\n'.join([PrettyPrintNode(n) for n in node.childNodes])
-
-  # Handle text nodes.
-  if node.nodeType == xml.dom.minidom.Node.TEXT_NODE:
-    # Wrap each paragraph in the text to fit in the 80 column limit.
-    wrapper = textwrap.TextWrapper()
-    wrapper.initial_indent = ' ' * indent
-    wrapper.subsequent_indent = ' ' * indent
-    wrapper.break_on_hyphens = False
-    wrapper.break_long_words = False
-    wrapper.width = WRAP_COLUMN
-    text = XmlEscape(node.data)
-    # Remove any common indent.
-    text = textwrap.dedent(text.strip('\n'))
-    lines = text.split('\n')
-    # Split the text into paragraphs at blank line boundaries.
-    paragraphs = [[]]
-    for l in lines:
-      if len(l.strip()) == 0 and len(paragraphs[-1]) > 0:
-        paragraphs.append([])
-      else:
-        paragraphs[-1].append(l)
-    # Remove trailing empty paragraph if present.
-    if len(paragraphs) > 0 and len(paragraphs[-1]) == 0:
-      paragraphs = paragraphs[:-1]
-    # Wrap each paragraph and separate with two newlines.
-    return '\n\n'.join([wrapper.fill('\n'.join(p)) for p in paragraphs])
-
-  # Handle element nodes.
-  if node.nodeType == xml.dom.minidom.Node.ELEMENT_NODE:
-    newlines_after_open, newlines_before_close, newlines_after_close = (
-      TAGS_THAT_HAVE_EXTRA_NEWLINE.get(node.tagName, (1, 1, 0)))
-    # Open the tag.
-    s = ' ' * indent + '<' + node.tagName
-
-    # Calculate how much space to allow for the '>' or '/>'.
-    closing_chars = 1
-    if not node.childNodes:
-      closing_chars = 2
-
-    # Pretty-print the attributes.
-    attributes = node.attributes.keys()
-    if attributes:
-      # Reorder the attributes.
-      if not node.tagName in ATTRIBUTE_ORDER:
-        unrecognized_attributes = attributes;
-      else:
-        unrecognized_attributes = (
-          [a for a in attributes if not a in ATTRIBUTE_ORDER[node.tagName]])
-        attributes = (
-          [a for a in ATTRIBUTE_ORDER[node.tagName] if a in attributes])
-
-      for a in unrecognized_attributes:
-        logging.error(
-            'Unrecognized attribute "%s" in tag "%s"' % (a, node.tagName))
-      if unrecognized_attributes:
-        raise Error()
-
-      for a in attributes:
-        value = XmlEscape(node.attributes[a].value)
-        # Replace sequences of whitespace with single spaces.
-        words = value.split()
-        a_str = ' %s="%s"' % (a, ' '.join(words))
-        # Start a new line if the attribute will make this line too long.
-        if LastLineLength(s) + len(a_str) + closing_chars > WRAP_COLUMN:
-          s += '\n' + ' ' * (indent + 3)
-        # Output everything up to the first quote.
-        s += ' %s="' % (a)
-        value_indent_level = LastLineLength(s)
-        # Output one word at a time, splitting to the next line where necessary.
-        column = value_indent_level
-        for i, word in enumerate(words):
-          # This is slightly too conservative since not every word will be
-          # followed by the closing characters...
-          if i > 0 and (column + len(word) + 1 + closing_chars > WRAP_COLUMN):
-            s = s.rstrip()  # remove any trailing whitespace
-            s += '\n' + ' ' * value_indent_level
-            column = value_indent_level
-          s += word + ' '
-          column += len(word) + 1
-        s = s.rstrip()  # remove any trailing whitespace
-        s += '"'
-      s = s.rstrip()  # remove any trailing whitespace
-
-    # Pretty-print the child nodes.
-    if node.childNodes:
-      s += '>'
-      # Calculate the new indent level for child nodes.
-      new_indent = indent
-      if node.tagName not in TAGS_THAT_DONT_INDENT:
-        new_indent += 2
-      child_nodes = node.childNodes
-
-      # Recursively pretty-print the child nodes.
-      child_nodes = [PrettyPrintNode(n, indent=new_indent) for n in child_nodes]
-      child_nodes = [c for c in child_nodes if len(c.strip()) > 0]
-
-      # Determine whether we can fit the entire node on a single line.
-      close_tag = '</%s>' % node.tagName
-      space_left = WRAP_COLUMN - LastLineLength(s) - len(close_tag)
-      if (node.tagName in TAGS_THAT_ALLOW_SINGLE_LINE and
-          len(child_nodes) == 1 and len(child_nodes[0].strip()) <= space_left):
-        s += child_nodes[0].strip()
-      else:
-        s += '\n' * newlines_after_open + '\n'.join(child_nodes)
-        s += '\n' * newlines_before_close + ' ' * indent
-      s += close_tag
-    else:
-      s += '/>'
-    s += '\n' * newlines_after_close
-    return s
-
-  # Handle comment nodes.
-  if node.nodeType == xml.dom.minidom.Node.COMMENT_NODE:
-    return '<!--%s-->\n' % node.data
-
-  # Ignore other node types. This could be a processing instruction (<? ... ?>)
-  # or cdata section (<![CDATA[...]]!>), neither of which are legal in the
-  # histograms XML at present.
-  logging.error('Ignoring unrecognized node data: %s' % node.toxml())
-  raise Error()
-
-
 def unsafeAppendChild(parent, child):
   """Append child to parent's list of children, ignoring the possibility that it
   is already in another node's childNodes list.  Requires that the previous
   parent of child is discarded (to avoid non-tree DOM graphs).
   This can provide a significant speedup as O(n^2) operations are removed (in
   particular, each child insertion avoids the need to traverse the old parent's
   entire list of children)."""
   child.parentNode = None
   parent.appendChild(child)
   child.parentNode = parent
@@ skipping 41 matching lines @@
 
   # Recursively handle other element nodes and other node types.
   for c in node.childNodes: TransformByAlphabetizing(c)
   return node
 
 
 def PrettyPrint(raw_xml):
   """Pretty-print the given XML.
 
   Args:
-    xml: The contents of the histograms XML file, as a string.
+    raw_xml: The contents of the histograms XML file, as a string.
 
   Returns:
     The pretty-printed version.
   """
   tree = xml.dom.minidom.parseString(raw_xml)
   tree = TransformByAlphabetizing(tree)
-  return PrettyPrintNode(tree)
+  return print_style.GetPrintStyle().PrettyPrintNode(tree)
 
 
 def main():
   logging.basicConfig(level=logging.INFO)
 
   presubmit = ('--presubmit' in sys.argv)
 
   histograms_filename = 'histograms.xml'
   histograms_backup_filename = 'histograms.before.pretty-print.xml'
 
@@ skipping 24 matching lines @@
     logging.error('Aborting parsing due to fatal errors.')
     sys.exit(1)
 
   if xml == pretty:
     logging.info('%s is correctly pretty-printed.' % histograms_filename)
     sys.exit(0)
   if presubmit:
     logging.info('%s is not formatted correctly; run pretty_print.py to fix.' %
                  histograms_filename)
     sys.exit(1)
-  if not diffutil.PromptUserToAcceptDiff(
+  if not diff_util.PromptUserToAcceptDiff(
       xml, pretty,
       'Is the prettified version acceptable?'):
     logging.error('Aborting')
     return
 
   logging.info('Creating backup file %s' % histograms_backup_filename)
   shutil.move(histograms_pathname, histograms_backup_pathname)
 
   logging.info('Writing new %s file' % histograms_filename)
   with open(histograms_pathname, 'wb') as f:
     f.write(pretty)
 
 
 if __name__ == '__main__':
   main()