Uploaded Test files

venv/Lib/site-packages/nbconvert/utils/pandoc.py

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+"""Utility for calling pandoc"""
+# Copyright (c) IPython Development Team.
+# Distributed under the terms of the Modified BSD License.
+
+from __future__ import print_function, absolute_import
+
+import subprocess
+import warnings
+import re
+from io import TextIOWrapper, BytesIO
+
+from nbconvert.utils.version import check_version
+import shutil
+
+from .exceptions import ConversionException
+
+_minimal_version = "1.12.1"
+_maximal_version = "3.0.0"
+
+
+def pandoc(source, fmt, to, extra_args=None, encoding='utf-8'):
+    """Convert an input string using pandoc.
+
+    Pandoc converts an input string `from` a format `to` a target format.
+
+    Parameters
+    ----------
+    source : string
+        Input string, assumed to be valid format `from`.
+    fmt : string
+        The name of the input format (markdown, etc.)
+    to : string
+        The name of the output format (html, etc.)
+
+    Returns
+    -------
+    out : unicode
+        Output as returned by pandoc.
+
+    Raises
+    ------
+    PandocMissing
+        If pandoc is not installed.
+    Any error messages generated by pandoc are printed to stderr.
+
+    """
+    cmd = ['pandoc', '-f', fmt, '-t', to]
+    if extra_args:
+        cmd.extend(extra_args)
+
+    # this will raise an exception that will pop us out of here
+    check_pandoc_version()
+    
+    # we can safely continue
+    p = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
+    out, _ = p.communicate(source.encode())
+    out = TextIOWrapper(BytesIO(out), encoding, 'replace').read()
+    return out.rstrip('\n')
+
+
+def get_pandoc_version():
+    """Gets the Pandoc version if Pandoc is installed.
+
+    If the minimal version is not met, it will probe Pandoc for its version, cache it and return that value.
+    If the minimal version is met, it will return the cached version and stop probing Pandoc
+    (unless `clean_cache()` is called).
+
+    Raises
+    ------
+    PandocMissing
+        If pandoc is unavailable.
+    """
+    global __version
+
+    if __version is None:
+        if not shutil.which('pandoc'):
+            raise PandocMissing()
+
+        out = subprocess.check_output(['pandoc', '-v'])
+        out_lines = out.splitlines()
+        version_pattern = re.compile(r"^\d+(\.\d+){1,}$")
+        for tok in out_lines[0].decode('ascii', 'replace').split():
+            if version_pattern.match(tok):
+                __version = tok
+                break
+    return __version
+
+
+def check_pandoc_version():
+    """Returns True if pandoc's version meets at least minimal version.
+
+    Raises
+    ------
+    PandocMissing
+        If pandoc is unavailable.
+    """
+    if check_pandoc_version._cached is not None:
+        return check_pandoc_version._cached
+
+    v = get_pandoc_version()
+    if v is None:
+        warnings.warn("Sorry, we cannot determine the version of pandoc.\n"
+                      "Please consider reporting this issue and include the"
+                      "output of pandoc --version.\nContinuing...",
+                      RuntimeWarning, stacklevel=2)
+        return False
+    ok = check_version(v, _minimal_version, max_v=_maximal_version)
+    check_pandoc_version._cached = ok
+    if not ok:
+        warnings.warn( "You are using an unsupported version of pandoc (%s).\n" % v +
+                       "Your version must be at least (%s) " % _minimal_version +
+                       "but less than (%s).\n" % _maximal_version +
+                       "Refer to https://pandoc.org/installing.html.\nContinuing with doubts...",
+                       RuntimeWarning, stacklevel=2)
+    return ok
+
+
+check_pandoc_version._cached = None
+
+#-----------------------------------------------------------------------------
+# Exception handling
+#-----------------------------------------------------------------------------
+class PandocMissing(ConversionException):
+    """Exception raised when Pandoc is missing."""
+    def __init__(self, *args, **kwargs):
+        super().__init__( "Pandoc wasn't found.\n" +
+                                             "Please check that pandoc is installed:\n" +
+                                             "https://pandoc.org/installing.html" )
+
+#-----------------------------------------------------------------------------
+# Internal state management
+#-----------------------------------------------------------------------------
+def clean_cache():
+    global __version
+    __version = None
+
+__version = None