Added virtual terminal sequence enabling to allow colorized output on Windows platforms.

slither/utils/colors.py

@@ -1,8 +1,9 @@
 from functools import partial
+import platform
 
 
 class Colors:
-    COLORIZATION_ENABLED = True
+    COLORIZATION_ENABLED = False
     RED = '\033[91m'
     GREEN = '\033[92m'
     YELLOW = '\033[93m'
@@ -18,8 +19,54 @@ def colorize(color, txt):
         return txt
 
 
+def enable_windows_virtual_terminal_sequences():
+    """
+    Sets the appropriate flags to enable virtual terminal sequences in a Windows command prompt.
+    Reference: https://docs.microsoft.com/en-us/windows/console/console-virtual-terminal-sequences
+    """
+
+    import ctypes
+    from ctypes.wintypes import DWORD, HANDLE
+
+    kernel32 = ctypes.windll.kernel32
+    virtual_terminal_flag = 0x04  # ENABLE_VIRTUAL_TERMINAL_PROCESSING
+
+    # Obtain our stdout/stderr handles.
+    handle_stdout = kernel32.GetStdHandle(-11)
+    handle_stderr = kernel32.GetStdHandle(-12)
+
+    # Loop for each stdout/stderr handle.
+    for current_handle in [handle_stdout, handle_stderr]:
+
+        # If we get a null handle, or fail any subsequent calls in this scope, we do not colorize any output.
+        if current_handle is None or current_handle == HANDLE(-1):
+            return False
+
+        # Try to obtain the current flags for the console.
+        current_mode = ctypes.wintypes.DWORD()
+        if not kernel32.GetConsoleMode(current_handle, ctypes.byref(current_mode)):
+            return False
+
+        # If the virtual terminal sequence processing is not yet enabled, we enable it.
+        if (current_mode.value & virtual_terminal_flag) == 0:
+            if not kernel32.SetConsoleMode(current_handle, current_mode.value | virtual_terminal_flag):
+                return False
+
+    return True
+
+
 def set_colorization_enabled(enabled):
-    Colors.COLORIZATION_ENABLED = enabled
+    """
+    Sets the enabled state of output colorization.
+    :param enabled: Boolean indicating whether output should be colorized.
+    :return: None
+    """
+    # If color is supposed to be enabled and this is windows, we have to enable console virtual terminal sequences:
+    if enabled and platform.system() == 'Windows':
+        Colors.COLORIZATION_ENABLED = enable_windows_virtual_terminal_sequences()
+    else:
+        # This is not windows so we can enable color immediately.
+        Colors.COLORIZATION_ENABLED = enabled
 
 
 green = partial(colorize, Colors.GREEN)