Include initial use of colorama

third_party/colorama/ansitowin32.py

Index: third_party/colorama/ansitowin32.py
diff --git a/third_party/colorama/ansitowin32.py b/third_party/colorama/ansitowin32.py
new file mode 100644
index 0000000000000000000000000000000000000000..48503fe41f64470b732c8fe0b3b31e81f926ae46
--- /dev/null
+++ b/third_party/colorama/ansitowin32.py
@@ -0,0 +1,189 @@
+
+import re
+import sys
+
+from .ansi import AnsiFore, AnsiBack, AnsiStyle, Style
+from .winterm import WinTerm, WinColor, WinStyle
+from .win32 import windll
+
+
+if windll is not None:
+    winterm = WinTerm()
+
+
+def is_a_tty(stream):
+    return hasattr(stream, 'isatty') and stream.isatty()
+
+
+class StreamWrapper(object):
+    '''
+    Wraps a stream (such as stdout), acting as a transparent proxy for all
+    attribute access apart from method 'write()', which is delegated to our
+    Converter instance.
+    '''
+    def __init__(self, wrapped, converter):
+        # double-underscore everything to prevent clashes with names of
+        # attributes on the wrapped stream object.
+        self.__wrapped = wrapped
+        self.__convertor = converter
+
+    def __getattr__(self, name):
+        return getattr(self.__wrapped, name)
+
+    def write(self, text):
+        self.__convertor.write(text)
+
+
+class AnsiToWin32(object):
+    '''
+    Implements a 'write()' method which, on Windows, will strip ANSI character
+    sequences from the text, and if outputting to a tty, will convert them into
+    win32 function calls.
+    '''
+    ANSI_RE = re.compile('\033\[((?:\d|;)*)([a-zA-Z])')
+
+    def __init__(self, wrapped, convert=None, strip=None, autoreset=False):
+        # The wrapped stream (normally sys.stdout or sys.stderr)
+        self.wrapped = wrapped
+
+        # should we reset colors to defaults after every .write()
+        self.autoreset = autoreset
+
+        # create the proxy wrapping our output stream
+        self.stream = StreamWrapper(wrapped, self)
+
+        on_windows = sys.platform.startswith('win')
+
+        # should we strip ANSI sequences from our output?
+        if strip is None:
+            strip = on_windows
+        self.strip = strip
+
+        # should we should convert ANSI sequences into win32 calls?
+        if convert is None:
+            convert = on_windows and is_a_tty(wrapped)
+        self.convert = convert
+
+        # dict of ansi codes to win32 functions and parameters
+        self.win32_calls = self.get_win32_calls()
+
+        # are we wrapping stderr?
+        self.on_stderr = self.wrapped is sys.stderr
+
+
+    def should_wrap(self):
+        '''
+        True if this class is actually needed. If false, then the output
+        stream will not be affected, nor will win32 calls be issued, so
+        wrapping stdout is not actually required. This will generally be
+        False on non-Windows platforms, unless optional functionality like
+        autoreset has been requested using kwargs to init()
+        '''
+        return self.convert or self.strip or self.autoreset
+
+
+    def get_win32_calls(self):
+        if self.convert and winterm:
+            return {
+                AnsiStyle.RESET_ALL: (winterm.reset_all, ),
+                AnsiStyle.BRIGHT: (winterm.style, WinStyle.BRIGHT),
+                AnsiStyle.DIM: (winterm.style, WinStyle.NORMAL),
+                AnsiStyle.NORMAL: (winterm.style, WinStyle.NORMAL),
+                AnsiFore.BLACK: (winterm.fore, WinColor.BLACK),
+                AnsiFore.RED: (winterm.fore, WinColor.RED),
+                AnsiFore.GREEN: (winterm.fore, WinColor.GREEN),
+                AnsiFore.YELLOW: (winterm.fore, WinColor.YELLOW),
+                AnsiFore.BLUE: (winterm.fore, WinColor.BLUE),
+                AnsiFore.MAGENTA: (winterm.fore, WinColor.MAGENTA),
+                AnsiFore.CYAN: (winterm.fore, WinColor.CYAN),
+                AnsiFore.WHITE: (winterm.fore, WinColor.GREY),
+                AnsiFore.RESET: (winterm.fore, ),
+                AnsiBack.BLACK: (winterm.back, WinColor.BLACK),
+                AnsiBack.RED: (winterm.back, WinColor.RED),
+                AnsiBack.GREEN: (winterm.back, WinColor.GREEN),
+                AnsiBack.YELLOW: (winterm.back, WinColor.YELLOW),
+                AnsiBack.BLUE: (winterm.back, WinColor.BLUE),
+                AnsiBack.MAGENTA: (winterm.back, WinColor.MAGENTA),
+                AnsiBack.CYAN: (winterm.back, WinColor.CYAN),
+                AnsiBack.WHITE: (winterm.back, WinColor.GREY),
+                AnsiBack.RESET: (winterm.back, ),
+            }
+
+
+    def write(self, text):
+        if self.strip or self.convert:
+            self.write_and_convert(text)
+        else:
+            self.wrapped.write(text)
+            self.wrapped.flush()
+        if self.autoreset:
+            self.reset_all()
+
+
+    def reset_all(self):
+        if self.convert:
+            self.call_win32('m', (0,))
+        elif is_a_tty(self.wrapped):
+            self.wrapped.write(Style.RESET_ALL)
+
+
+    def write_and_convert(self, text):
+        '''
+        Write the given text to our wrapped stream, stripping any ANSI
+        sequences from the text, and optionally converting them into win32
+        calls.
+        '''
+        cursor = 0
+        for match in self.ANSI_RE.finditer(text):
+            start, end = match.span()
+            self.write_plain_text(text, cursor, start)
+            self.convert_ansi(*match.groups())
+            cursor = end
+        self.write_plain_text(text, cursor, len(text))
+
+
+    def write_plain_text(self, text, start, end):
+        if start < end:
+            self.wrapped.write(text[start:end])
+            self.wrapped.flush()
+
+
+    def convert_ansi(self, paramstring, command):
+        if self.convert:
+            params = self.extract_params(paramstring)
+            self.call_win32(command, params)
+
+
+    def extract_params(self, paramstring):
+        def split(paramstring):
+            for p in paramstring.split(';'):
+                if p != '':
+                    yield int(p)
+        return tuple(split(paramstring))
+
+
+    def call_win32(self, command, params):
+        if params == []:
+            params = [0]
+        if command == 'm':
+            for param in params:
+                if param in self.win32_calls:
+                    func_args = self.win32_calls[param]
+                    func = func_args[0]
+                    args = func_args[1:]
+                    kwargs = dict(on_stderr=self.on_stderr)
+                    func(*args, **kwargs)
+        elif command in ('H', 'f'): # set cursor position
+            func = winterm.set_cursor_position
+            func(params, on_stderr=self.on_stderr)
+        elif command in ('J'):
+            func = winterm.erase_data
+            func(params, on_stderr=self.on_stderr)
+        elif command == 'A':
+            if params == () or params == None:
+                num_rows = 1
+            else:
+                num_rows = params[0]
+            func = winterm.cursor_up
+            func(num_rows, on_stderr=self.on_stderr)
+