Add "friendly grayscale" theme (#1273)

Fixes https://github.com/pygments/pygments/issues/1040

2 files changed, 76 insertions, 0 deletions

diff --git a/pygments/styles/__init__.py b/pygments/styles/__init__.py
index 7653376b..d75de1a5 100644
--- a/pygments/styles/__init__.py
+++ b/pygments/styles/__init__.py
@@ -17,6 +17,7 @@ STYLE_MAP = {
     'default':  'default::DefaultStyle',
     'emacs':    'emacs::EmacsStyle',
     'friendly': 'friendly::FriendlyStyle',
+    'friendly_grayscale': 'friendly_grayscale::FriendlyGrayscaleStyle',
     'colorful': 'colorful::ColorfulStyle',
     'autumn':   'autumn::AutumnStyle',
     'murphy':   'murphy::MurphyStyle',
diff --git a/pygments/styles/friendly_grayscale.py b/pygments/styles/friendly_grayscale.py
new file mode 100644
index 00000000..d13bc396
--- /dev/null
+++ b/pygments/styles/friendly_grayscale.py
@@ -0,0 +1,75 @@
+# -*- coding: utf-8 -*-
+"""
+    pygments.styles.friendly_grayscale
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    A style based on friendly style.
+    The color values of the friendly style have been converted to grayscale
+    using the luminosity value calculated by
+    http://www.workwithcolor.com/color-converter-01.htm
+
+    :copyright: Copyright 2006-2019 by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+from pygments.style import Style
+from pygments.token import Keyword, Name, Comment, String, Error, \
+     Number, Operator, Generic, Whitespace
+
+
+class FriendlyGrayscaleStyle(Style):
+    """
+    A modern grayscale style based on the friendly style.
+    """
+
+    background_color = "#f0f0f0"
+    default_style = ""
+
+    styles = {
+        Whitespace:                "#bbbbbb",
+        Comment:                   "italic #959595",
+        Comment.Preproc:           "noitalic #575757",
+        Comment.Special:           "noitalic bg:#F4F4F4",
+
+        Keyword:                   "bold #575757",
+        Keyword.Pseudo:            "nobold",
+        Keyword.Type:              "nobold #4F4F4F",
+
+        Operator:                  "#666666",
+        Operator.Word:             "bold #575757",
+
+        Name.Builtin:              "#575757",
+        Name.Function:             "#3F3F3F",
+        Name.Class:                "bold #7E7E7E",
+        Name.Namespace:            "bold #7E7E7E",
+        Name.Exception:            "#575757",
+        Name.Variable:             "#9A9A9A",
+        Name.Constant:             "#A5A5A5",
+        Name.Label:                "bold #363636",
+        Name.Entity:               "bold #848484",
+        Name.Attribute:            "#707070",
+        Name.Tag:                  "bold #3B3B3B",
+        Name.Decorator:            "bold #555555",
+
+        String:                    "#717171",
+        String.Doc:                "italic",
+        String.Interpol:           "italic #9F9F9F",
+        String.Escape:             "bold #717171",
+        String.Regex:              "#575757",
+        String.Symbol:             "#676767",
+        String.Other:              "#7E7E7E",
+        Number:                    "#888888",
+
+        Generic.Heading:           "bold #373737",
+        Generic.Subheading:        "bold #5A5A5A",
+        Generic.Deleted:           "#545454",
+        Generic.Inserted:          "#7D7D7D",
+        Generic.Error:             "#898989",
+        Generic.Emph:              "italic",
+        Generic.Strong:            "bold",
+        Generic.Prompt:            "bold #7E7E7E",
+        Generic.Output:            "#888888",
+        Generic.Traceback:         "#6D6D6D",
+
+        Error:                     "border:#898989"
+    }