New environment var

Author: willmcgugan

.pre-commit-config.yaml

@@ -20,7 +20,6 @@ repos:
   - repo: https://github.com/pre-commit/pygrep-hooks
     rev: v1.10.0
     hooks:
-      - id: python-check-mock-methods
       - id: python-no-log-warn
       - id: python-use-type-annotations
       - id: rst-directive-colons

docs/source/console.rst

@@ -420,11 +420,15 @@ Rich respects some standard environment variables.
 
 Setting the environment variable ``TERM`` to ``"dumb"`` or ``"unknown"`` will disable color/style and some features that require moving the cursor, such as progress bars.
 
-If the environment variable ``FORCE_COLOR`` is set, then color/styles will be enabled regardless of the value of ``TERM``. This is useful on CI systems which aren't terminals but can none-the-less display ANSI escape sequences.
+If the environment variable ``FORCE_COLOR`` is set and non-empty, then color/styles will be enabled regardless of the value of ``TERM``.
 
-If the environment variable ``NO_COLOR`` is set, Rich will disable all color in the output. This takes precedence over ``FORCE_COLOR``. See `no_color <https://no-color.org/>`_ for details.
+If the environment variable ``NO_COLOR`` is set, Rich will disable all color in the output. ``NO_COLOR`` takes precedence over ``FORCE_COLOR``. See `no_color <https://no-color.org/>`_ for details.
 
 .. note::
     The ``NO_COLOR`` environment variable removes *color* only. Styles such as dim, bold, italic, underline etc. are preserved.
 
-If ``width`` / ``height`` arguments are not explicitly provided as arguments to ``Console`` then the environment variables ``COLUMNS``/``LINES`` can be used to set the console width/height. ``JUPYTER_COLUMNS``/``JUPYTER_LINES`` behave similarly and are used in Jupyter.
+The environment variable ``TTY_COMPATIBLE`` is used to override Rich's auto-detection of terminal support. If ``TTY_COMPATIBLE`` is set to ``1`` then rich will assume it is writing to a terminal (or a device that can handle escape sequences). If ``TTY_COMPATIBLE`` is set to ``"0"``, then Rich will assume that it is not writing to a terminal. If the variable is not set, or any other value, then Rich will attempt to auto-detect terminal support. If you want Rich output in CI or Github Actions, then you should set ``TTY_COMPATIBLE=1``.
+
+Note that these variable set the default behavior. If you explicitly set ``force_terminal`` in the Console constructor, then this will take precedence over the environment variable.
+
+If ``width`` / ``height`` arguments are not explicitly provided as arguments to ``Console`` then the environment variables ``COLUMNS`` / ``LINES`` can be used to set the console width / height. ``JUPYTER_COLUMNS`` / ``JUPYTER_LINES`` behave similarly and are used in Jupyter.

rich/console.py

@@ -500,7 +500,7 @@ def group(fit: bool = True) -> Callable[..., Callable[..., Group]]:
     """
 
     def decorator(
-        method: Callable[..., Iterable[RenderableType]]
+        method: Callable[..., Iterable[RenderableType]],
     ) -> Callable[..., Group]:
         """Convert a method that returns an iterable of renderables in to a Group."""
 
@@ -933,11 +933,13 @@ def is_terminal(self) -> bool:
 
         Returns:
             bool: True if the console writing to a device capable of
-            understanding terminal codes, otherwise False.
+                understanding escape sequences, otherwise False.
         """
+        # If dev has explicitly set this value, return it
         if self._force_terminal is not None:
             return self._force_terminal
 
+        # Fudge for Idle
         if hasattr(sys.stdin, "__module__") and sys.stdin.__module__.startswith(
             "idlelib"
         ):
@@ -948,12 +950,22 @@ def is_terminal(self) -> bool:
             # return False for Jupyter, which may have FORCE_COLOR set
             return False
 
-        # If FORCE_COLOR env var has any value at all, we assume a terminal.
-        force_color = self._environ.get("FORCE_COLOR")
-        if force_color is not None:
-            self._force_terminal = True
+        environ = self._environ
+
+        tty_compatible = environ.get("TTY_COMPATIBLE", "")
+        # 0 indicates device is not tty compatible
+        if tty_compatible == "0":
+            return False
+        # 1 indicates device is tty compatible
+        if tty_compatible == "1":
             return True
 
+        # https://force-color.org/
+        force_color = environ.get("FORCE_COLOR")
+        if force_color is not None:
+            return force_color != ""
+
+        # Any other value defaults to auto detect
         isatty: Optional[Callable[[], bool]] = getattr(self.file, "isatty", None)
         try:
             return False if isatty is None else isatty()