Change actions.txt to actions.xml

tools/metrics/common/pretty_print_xml.py

+import logging

[Alexei Svitkine (slow), 2014/01/31 19:56:58]

Needs some comments / copyright block at the top.

[yao, 2014/02/03 14:39:20]

Done.

+import textwrap
+import xml.dom.minidom
+
+WRAP_COLUMN = 80
+
+
+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
+
+
+class XmlStyle(object):
+  """A class that stores all style specification for an output xml file."""
+
+  def __init__(self, attribute_order, tags_that_have_extra_newline,
+               tags_that_dont_indent, tags_that_allow_single_line):
+    # List of tag names for top-level nodes whose children are not indented.
+    self.attribute_order = attribute_order
+    self.tags_that_have_extra_newline = tags_that_have_extra_newline
+    self.tags_that_dont_indent = tags_that_dont_indent
+    self.tags_that_allow_single_line = tags_that_allow_single_line
+
+
+def PrettyPrintNode(node, xml_style, indent=0):

[Alexei Svitkine (slow), 2014/01/31 19:56:58]

Can you make it so this file is marked as being branched/copied from
tools/metrics/histograms/pretty_print.py so the diff is easier to read?

[yao, 2014/02/03 14:39:20]

Done.

+  """Pretty-prints the given XML node at the given indent level.
+
+  Args:
+    node: The minidom node to pretty-print.
+    xml_style: An XmlStyle object that represents the style requirement of the
+        output xml file.
+    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, xml_style) 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 = (
+        xml_style.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 node.tagName not in xml_style.attribute_order:
+        unrecognized_attributes = attributes
+      else:
+        unrecognized_attributes = (
+            [a for a in attributes
+             if a not in xml_style.attribute_order[node.tagName]])
+        attributes = [a for a in xml_style.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 xml_style.tags_that_dont_indent:
+        new_indent += 2
+      child_nodes = node.childNodes
+
+      # Recursively pretty-print the child nodes.
+      child_nodes = [PrettyPrintNode(n, xml_style, 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 xml_style.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()