Add truecolor support (#155)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Sorin Sbarnea <[email protected]>

Author: 3 people

ansi2html/converter.py

@@ -26,7 +26,12 @@
 from collections import OrderedDict
 from typing import Iterator, List, Optional, Set, Tuple, Union
 
-from ansi2html.style import SCHEME, get_styles
+from ansi2html.style import (
+    SCHEME,
+    add_truecolor_style_rule,
+    get_styles,
+    pop_truecolor_styles,
+)
 
 if sys.version_info >= (3, 8):
     from importlib.metadata import version
@@ -56,18 +61,20 @@
 ANSI_VISIBILITY_OFF = 8
 ANSI_FOREGROUND_CUSTOM_MIN = 30
 ANSI_FOREGROUND_CUSTOM_MAX = 37
-ANSI_FOREGROUND_256 = 38
+ANSI_FOREGROUND = 38
 ANSI_FOREGROUND_DEFAULT = 39
 ANSI_BACKGROUND_CUSTOM_MIN = 40
 ANSI_BACKGROUND_CUSTOM_MAX = 47
-ANSI_BACKGROUND_256 = 48
+ANSI_BACKGROUND = 48
 ANSI_BACKGROUND_DEFAULT = 49
 ANSI_NEGATIVE_ON = 7
 ANSI_NEGATIVE_OFF = 27
 ANSI_FOREGROUND_HIGH_INTENSITY_MIN = 90
 ANSI_FOREGROUND_HIGH_INTENSITY_MAX = 97
 ANSI_BACKGROUND_HIGH_INTENSITY_MIN = 100
 ANSI_BACKGROUND_HIGH_INTENSITY_MAX = 107
+ANSI_256_COLOR_ID = 5
+ANSI_TRUECOLOR_ID = 2
 
 VT100_BOX_CODES = {
     "0x71": "─",
@@ -131,11 +138,11 @@ def reset(self) -> None:
         self.underline: int = ANSI_UNDERLINE_OFF
         self.crossedout: int = ANSI_CROSSED_OUT_OFF
         self.visibility: int = ANSI_VISIBILITY_ON
-        self.foreground: Tuple[int, Optional[int]] = (ANSI_FOREGROUND_DEFAULT, None)
-        self.background: Tuple[int, Optional[int]] = (ANSI_BACKGROUND_DEFAULT, None)
+        self.foreground: Tuple[int, Optional[str]] = (ANSI_FOREGROUND_DEFAULT, None)
+        self.background: Tuple[int, Optional[str]] = (ANSI_BACKGROUND_DEFAULT, None)
         self.negative: int = ANSI_NEGATIVE_OFF
 
-    def adjust(self, ansi_code: int, parameter: Optional[int] = None) -> None:
+    def adjust(self, ansi_code: int, parameter: Optional[str] = None) -> None:
         if ansi_code in (
             ANSI_INTENSITY_INCREASED,
             ANSI_INTENSITY_REDUCED,
@@ -160,7 +167,7 @@ def adjust(self, ansi_code: int, parameter: Optional[int] = None) -> None:
             <= ANSI_FOREGROUND_HIGH_INTENSITY_MAX
         ):
             self.foreground = (ansi_code, None)
-        elif ansi_code == ANSI_FOREGROUND_256:
+        elif ansi_code == ANSI_FOREGROUND:
             self.foreground = (ansi_code, parameter)
         elif ansi_code == ANSI_FOREGROUND_DEFAULT:
             self.foreground = (ansi_code, None)
@@ -172,13 +179,25 @@ def adjust(self, ansi_code: int, parameter: Optional[int] = None) -> None:
             <= ANSI_BACKGROUND_HIGH_INTENSITY_MAX
         ):
             self.background = (ansi_code, None)
-        elif ansi_code == ANSI_BACKGROUND_256:
+        elif ansi_code == ANSI_BACKGROUND:
             self.background = (ansi_code, parameter)
         elif ansi_code == ANSI_BACKGROUND_DEFAULT:
             self.background = (ansi_code, None)
         elif ansi_code in (ANSI_NEGATIVE_ON, ANSI_NEGATIVE_OFF):
             self.negative = ansi_code
 
+    def adjust_truecolor(self, ansi_code: int, r: int, g: int, b: int) -> None:
+        parameter = "{:03d}{:03d}{:03d}".format(
+            r, g, b
+        )  # r=1, g=64, b=255 -> 001064255
+
+        is_foreground = ansi_code == ANSI_FOREGROUND
+        add_truecolor_style_rule(is_foreground, ansi_code, r, g, b, parameter)
+        if is_foreground:
+            self.foreground = (ansi_code, parameter)
+        else:
+            self.background = (ansi_code, parameter)
+
     def to_css_classes(self) -> List[str]:
         css_classes: List[str] = []
 
@@ -189,7 +208,7 @@ def append_unless_default(output: List[str], value: int, default: int) -> None:
 
         def append_color_unless_default(
             output: List[str],
-            color: Tuple[int, Optional[int]],
+            color: Tuple[int, Optional[str]],
             default: int,
             negative: bool,
             neg_css_class: str,
@@ -198,7 +217,7 @@ def append_color_unless_default(
             if value != default:
                 prefix = "inv" if negative else "ansi"
                 css_class_index = (
-                    str(value) if (parameter is None) else "%d-%d" % (value, parameter)
+                    str(value) if (parameter is None) else "%d-%s" % (value, parameter)
                 )
                 output.append(prefix + css_class_index)
             elif negative:
@@ -297,7 +316,6 @@ def __init__(
         self.title = title
         self._attrs: Attributes
         self.hyperref = False
-
         if inline:
             self.styles = dict(
                 [
@@ -449,8 +467,14 @@ def _handle_ansi_code(
 
                 if v == ANSI_FULL_RESET:
                     last_null_index = i
-                elif v in (ANSI_FOREGROUND_256, ANSI_BACKGROUND_256):
-                    skip_after_index = i + 2
+                elif v in (ANSI_FOREGROUND, ANSI_BACKGROUND):
+                    try:
+                        x_bit_color_id = params[i + 1]
+                    except IndexError:
+                        x_bit_color_id = -1
+                    is_256_color = x_bit_color_id == ANSI_256_COLOR_ID
+                    shift = 2 if is_256_color else 4
+                    skip_after_index = i + shift
 
             # Process reset marker, drop everything before
             if last_null_index is not None:
@@ -472,12 +496,28 @@ def _handle_ansi_code(
                 if i <= skip_after_index:
                     continue
 
-                if v in (ANSI_FOREGROUND_256, ANSI_BACKGROUND_256):
+                is_x_bit_color = v in (ANSI_FOREGROUND, ANSI_BACKGROUND)
+                try:
+                    x_bit_color_id = params[i + 1]
+                except IndexError:
+                    x_bit_color_id = -1
+                is_256_color = x_bit_color_id == ANSI_256_COLOR_ID
+                is_truecolor = x_bit_color_id == ANSI_TRUECOLOR_ID
+                if is_x_bit_color and is_256_color:
                     try:
-                        parameter: Optional[int] = params[i + 2]
+                        parameter: Optional[str] = str(params[i + 2])
                     except IndexError:
                         continue
                     skip_after_index = i + 2
+                elif is_x_bit_color and is_truecolor:
+                    try:
+                        state.adjust_truecolor(
+                            v, params[i + 2], params[i + 3], params[i + 4]
+                        )
+                    except IndexError:
+                        continue
+                    skip_after_index = i + 4
+                    continue
                 else:
                     parameter = None
                 state.adjust(v, parameter=parameter)
@@ -495,6 +535,7 @@ def _handle_ansi_code(
             styles_used.update(css_classes)
 
             if self.inline:
+                self.styles.update(pop_truecolor_styles())
                 if self.latex:
                     style = [
                         self.styles[klass].kwl[0][1]

ansi2html/style.py

@@ -17,7 +17,7 @@
 #    <http://www.gnu.org/licenses/>.
 
 
-from typing import List
+from typing import Dict, List
 
 
 class Rule:
@@ -166,6 +166,9 @@ def index2(grey: int) -> str:
     ),
 }
 
+# to be filled in runtime, when truecolor found
+truecolor_rules: List[Rule] = []
+
 
 def intensify(color: str, dark_bg: bool, amount: int = 64) -> str:
     if not dark_bg:
@@ -267,4 +270,26 @@ def get_styles(
         css.append(Rule(".ansi48-%s" % index2(grey), background=level(grey)))
         css.append(Rule(".inv48-%s" % index2(grey), color=level(grey)))
 
+    css.extend(truecolor_rules)
+
     return css
+
+
+# as truecolor encoding has 16 millions colors, adding only used colors during parsing
+def add_truecolor_style_rule(
+    is_foreground: bool, ansi_code: int, r: int, g: int, b: int, parameter: str
+) -> None:
+    rule_name = ".ansi{}-{}".format(ansi_code, parameter)
+    color = "#{:02X}{:02X}{:02X}".format(r, g, b)
+    if is_foreground:
+        rule = Rule(rule_name, color=color)
+    else:
+        rule = Rule(rule_name, background_color=color)
+    truecolor_rules.append(rule)
+
+
+def pop_truecolor_styles() -> Dict[str, Rule]:
+    global truecolor_rules  # pylint: disable=global-statement
+    styles = dict([(item.klass.strip("."), item) for item in truecolor_rules])
+    truecolor_rules = []
+    return styles

tests/test_ansi2html.py

@@ -417,6 +417,55 @@ def test_latex_linkify(self) -> None:
         latex = Ansi2HTMLConverter(latex=True, inline=True, linkify=True).convert(ansi)
         assert target in latex
 
+    def test_truecolor(self) -> None:
+        ansi = (
+            "\u001b[38;2;255;102;102m 1 \u001b[0m "
+            + "\u001b[38;2;0;0;255m 2 \u001b[0m "
+            + "\u001b[48;2;65;105;225m 3 \u001b[0m"
+        )
+        target = (
+            '<span class="ansi38-255102102"> 1 </span> '
+            + '<span class="ansi38-000000255"> 2 </span> '
+            + '<span class="ansi48-065105225"> 3 </span>'
+        )
+        html = Ansi2HTMLConverter().convert(ansi)
+        assert target in html
+
+    def test_truecolor_inline(self) -> None:
+        ansi = (
+            "\u001b[38;2;255;102;102m 1 \u001b[0m "
+            + "\u001b[38;2;0;0;255m 2 \u001b[0m "
+            + "\u001b[48;2;65;105;225m 3 \u001b[0m"
+        )
+        target = (
+            '<span style="color: #FF6666"> 1 </span> '
+            + '<span style="color: #0000FF"> 2 </span> '
+            + '<span style="background-color: #4169E1"> 3 </span>'
+        )
+        html = Ansi2HTMLConverter(inline=True).convert(ansi)
+        assert target in html
+
+    def test_truecolor_malformed(self) -> None:
+        ansi = "\u001b[38;2;255;102m malformed \u001b[0m "
+        #                         ^ e.g. ";102" missed
+        target = '<span class="ansi2 ansi102"> malformed </span> '
+        html = Ansi2HTMLConverter().convert(ansi)
+        assert target in html
+
+    def test_256_color_malformed(self) -> None:
+        ansi = "\u001b[38;5m malformed \u001b[0m "
+        #                 ^ e.g. ";255" missed
+        target = '<span class="ansi5"> malformed </span> '
+        html = Ansi2HTMLConverter().convert(ansi)
+        assert target in html
+
+    def test_x_bit_color_malformed(self) -> None:
+        ansi = "\u001b[38m malformed \u001b[0m "
+        #               ^ e.g. ";5;255m" missed
+        target = '<span class="ansi38"> malformed </span> '
+        html = Ansi2HTMLConverter().convert(ansi)
+        assert target in html
+
     def test_command_script(self) -> None:
         result = run(["ansi2html", "--version"], check=True)
         assert result.returncode == 0