diff env/lib/python3.9/site-packages/bs4/diagnose.py @ 0:4f3585e2f14b draft default tip

"planemo upload commit 60cee0fc7c0cda8592644e1aad72851dec82c959"
author shellac
date Mon, 22 Mar 2021 18:12:50 +0000
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/env/lib/python3.9/site-packages/bs4/diagnose.py	Mon Mar 22 18:12:50 2021 +0000
@@ -0,0 +1,242 @@
+"""Diagnostic functions, mainly for use when doing tech support."""
+
+# Use of this source code is governed by the MIT license.
+__license__ = "MIT"
+
+import cProfile
+from io import StringIO
+from html.parser import HTMLParser
+import bs4
+from bs4 import BeautifulSoup, __version__
+from bs4.builder import builder_registry
+
+import os
+import pstats
+import random
+import tempfile
+import time
+import traceback
+import sys
+import cProfile
+
+def diagnose(data):
+    """Diagnostic suite for isolating common problems.
+
+    :param data: A string containing markup that needs to be explained.
+    :return: None; diagnostics are printed to standard output.
+    """
+    print(("Diagnostic running on Beautiful Soup %s" % __version__))
+    print(("Python version %s" % sys.version))
+
+    basic_parsers = ["html.parser", "html5lib", "lxml"]
+    for name in basic_parsers:
+        for builder in builder_registry.builders:
+            if name in builder.features:
+                break
+        else:
+            basic_parsers.remove(name)
+            print((
+                "I noticed that %s is not installed. Installing it may help." %
+                name))
+
+    if 'lxml' in basic_parsers:
+        basic_parsers.append("lxml-xml")
+        try:
+            from lxml import etree
+            print(("Found lxml version %s" % ".".join(map(str,etree.LXML_VERSION))))
+        except ImportError as e:
+            print(
+                "lxml is not installed or couldn't be imported.")
+
+
+    if 'html5lib' in basic_parsers:
+        try:
+            import html5lib
+            print(("Found html5lib version %s" % html5lib.__version__))
+        except ImportError as e:
+            print(
+                "html5lib is not installed or couldn't be imported.")
+
+    if hasattr(data, 'read'):
+        data = data.read()
+    elif data.startswith("http:") or data.startswith("https:"):
+        print(('"%s" looks like a URL. Beautiful Soup is not an HTTP client.' % data))
+        print("You need to use some other library to get the document behind the URL, and feed that document to Beautiful Soup.")
+        return
+    else:
+        try:
+            if os.path.exists(data):
+                print(('"%s" looks like a filename. Reading data from the file.' % data))
+                with open(data) as fp:
+                    data = fp.read()
+        except ValueError:
+            # This can happen on some platforms when the 'filename' is
+            # too long. Assume it's data and not a filename.
+            pass
+        print("")
+
+    for parser in basic_parsers:
+        print(("Trying to parse your markup with %s" % parser))
+        success = False
+        try:
+            soup = BeautifulSoup(data, features=parser)
+            success = True
+        except Exception as e:
+            print(("%s could not parse the markup." % parser))
+            traceback.print_exc()
+        if success:
+            print(("Here's what %s did with the markup:" % parser))
+            print((soup.prettify()))
+
+        print(("-" * 80))
+
+def lxml_trace(data, html=True, **kwargs):
+    """Print out the lxml events that occur during parsing.
+
+    This lets you see how lxml parses a document when no Beautiful
+    Soup code is running. You can use this to determine whether
+    an lxml-specific problem is in Beautiful Soup's lxml tree builders
+    or in lxml itself.
+
+    :param data: Some markup.
+    :param html: If True, markup will be parsed with lxml's HTML parser.
+       if False, lxml's XML parser will be used.
+    """
+    from lxml import etree
+    for event, element in etree.iterparse(StringIO(data), html=html, **kwargs):
+        print(("%s, %4s, %s" % (event, element.tag, element.text)))
+
+class AnnouncingParser(HTMLParser):
+    """Subclass of HTMLParser that announces parse events, without doing
+    anything else.
+
+    You can use this to get a picture of how html.parser sees a given
+    document. The easiest way to do this is to call `htmlparser_trace`.
+    """
+
+    def _p(self, s):
+        print(s)
+
+    def handle_starttag(self, name, attrs):
+        self._p("%s START" % name)
+
+    def handle_endtag(self, name):
+        self._p("%s END" % name)
+
+    def handle_data(self, data):
+        self._p("%s DATA" % data)
+
+    def handle_charref(self, name):
+        self._p("%s CHARREF" % name)
+
+    def handle_entityref(self, name):
+        self._p("%s ENTITYREF" % name)
+
+    def handle_comment(self, data):
+        self._p("%s COMMENT" % data)
+
+    def handle_decl(self, data):
+        self._p("%s DECL" % data)
+
+    def unknown_decl(self, data):
+        self._p("%s UNKNOWN-DECL" % data)
+
+    def handle_pi(self, data):
+        self._p("%s PI" % data)
+
+def htmlparser_trace(data):
+    """Print out the HTMLParser events that occur during parsing.
+
+    This lets you see how HTMLParser parses a document when no
+    Beautiful Soup code is running.
+
+    :param data: Some markup.
+    """
+    parser = AnnouncingParser()
+    parser.feed(data)
+
+_vowels = "aeiou"
+_consonants = "bcdfghjklmnpqrstvwxyz"
+
+def rword(length=5):
+    "Generate a random word-like string."
+    s = ''
+    for i in range(length):
+        if i % 2 == 0:
+            t = _consonants
+        else:
+            t = _vowels
+        s += random.choice(t)
+    return s
+
+def rsentence(length=4):
+    "Generate a random sentence-like string."
+    return " ".join(rword(random.randint(4,9)) for i in range(length))
+        
+def rdoc(num_elements=1000):
+    """Randomly generate an invalid HTML document."""
+    tag_names = ['p', 'div', 'span', 'i', 'b', 'script', 'table']
+    elements = []
+    for i in range(num_elements):
+        choice = random.randint(0,3)
+        if choice == 0:
+            # New tag.
+            tag_name = random.choice(tag_names)
+            elements.append("<%s>" % tag_name)
+        elif choice == 1:
+            elements.append(rsentence(random.randint(1,4)))
+        elif choice == 2:
+            # Close a tag.
+            tag_name = random.choice(tag_names)
+            elements.append("</%s>" % tag_name)
+    return "<html>" + "\n".join(elements) + "</html>"
+
+def benchmark_parsers(num_elements=100000):
+    """Very basic head-to-head performance benchmark."""
+    print(("Comparative parser benchmark on Beautiful Soup %s" % __version__))
+    data = rdoc(num_elements)
+    print(("Generated a large invalid HTML document (%d bytes)." % len(data)))
+    
+    for parser in ["lxml", ["lxml", "html"], "html5lib", "html.parser"]:
+        success = False
+        try:
+            a = time.time()
+            soup = BeautifulSoup(data, parser)
+            b = time.time()
+            success = True
+        except Exception as e:
+            print(("%s could not parse the markup." % parser))
+            traceback.print_exc()
+        if success:
+            print(("BS4+%s parsed the markup in %.2fs." % (parser, b-a)))
+
+    from lxml import etree
+    a = time.time()
+    etree.HTML(data)
+    b = time.time()
+    print(("Raw lxml parsed the markup in %.2fs." % (b-a)))
+
+    import html5lib
+    parser = html5lib.HTMLParser()
+    a = time.time()
+    parser.parse(data)
+    b = time.time()
+    print(("Raw html5lib parsed the markup in %.2fs." % (b-a)))
+
+def profile(num_elements=100000, parser="lxml"):
+    """Use Python's profiler on a randomly generated document."""
+    filehandle = tempfile.NamedTemporaryFile()
+    filename = filehandle.name
+
+    data = rdoc(num_elements)
+    vars = dict(bs4=bs4, data=data, parser=parser)
+    cProfile.runctx('bs4.BeautifulSoup(data, parser)' , vars, vars, filename)
+
+    stats = pstats.Stats(filename)
+    # stats.strip_dirs()
+    stats.sort_stats("cumulative")
+    stats.print_stats('_html5lib|bs4', 50)
+
+# If this file is run as a script, standard input is diagnosed.
+if __name__ == '__main__':
+    diagnose(sys.stdin.read())