[MRG] Add syntax highlighting to code blocks

present/effects.py

@@ -138,19 +138,6 @@ def _base(screen, element, row, fg_color, bg_color, attr=0):
     return [base]
 
 
-def _code(screen, element, row):
-    code = Print(
-        screen,
-        Text(element.render()),
-        row,
-        colour=Screen.COLOUR_WHITE,
-        bg=Screen.COLOUR_BLACK,
-        transparent=False,
-    )
-
-    return [code]
-
-
 def _codio(screen, element, row):
     codio = Print(
         screen,

present/slide.py

@@ -92,13 +92,16 @@ def pad(s, fill=" "):
         lines.insert(0, top)
         lines.append(bottom)
 
-        return "\n".join(lines)
+        return lines
 
     @property
     def size(self):
         return len(self.obj["text"].splitlines())
 
-    def render(self):
+    def lang(self):
+        return self.obj["info"]
+
+    def padded_lines(self):
         return self.pad(self.obj["text"])
 
 
@@ -407,6 +410,7 @@ def __init__(self, elements=None):
         self.effect = None
         self.fg_color = 0
         self.bg_color = 7
+        self.code_blocks = []
 
         _elements = []
 

present/slideshow.py

@@ -7,11 +7,16 @@
 from asciimatics.effects import Print
 from asciimatics.event import KeyboardEvent
 from asciimatics.exceptions import ResizeScreenError, StopApplication
+from asciimatics.parsers import AnsiTerminalParser
+from asciimatics.strings import ColouredText
+
+from pygments import highlight
+from pygments.lexers import get_lexer_by_name
+from pygments.formatters import Terminal256Formatter
 
 from .effects import (
     _reset,
     _base,
-    _code,
     _codio,
     _image,
     _fireworks,
@@ -23,11 +28,33 @@
 )
 
 
+def render_code_block(screen, block, row):
+    # Divide the width by 3
+    column = int(screen.dimensions[1] / 3)
+    lexer = get_lexer_by_name(block.lang())
+
+    for cur_row, line in enumerate(block.padded_lines(), start=row):
+        coded_text = highlight(line, lexer, Terminal256Formatter())
+        text = ColouredText(
+            coded_text,
+            AnsiTerminalParser(),
+        )
+        screen.paint(
+            text,
+            column,
+            cur_row,
+            colour_map=text.colour_map,
+        )
+
+
 class Slide(Scene):
-    def __init__(self, show, effects, fg_color, bg_color):
+    def __init__(self, show, slide):
         self.show = show
-        self.fg_color = fg_color
-        self.bg_color = bg_color
+        self.fg_color = slide.fg_color
+        self.bg_color = slide.bg_color
+        self.code_blocks = slide.code_blocks
+        effects = show.build_scene(slide)
+
         super(Slide, self).__init__(effects)
 
     def _reset(self):
@@ -93,7 +120,7 @@ def __enter__(self):
     def __exit__(self, type, value, traceback):
         self.screen.close()
 
-    def get_effects(self, slide):
+    def build_scene(self, slide):
         effects = []
         transparent = True
         elements = slide.elements
@@ -112,7 +139,8 @@ def get_effects(self, slide):
         pad = 2
         for e in elements:
             if e.type == "code":
-                effects.extend(_code(self.screen, e, row))
+                # Add the element + row to the slide's code_blocks list
+                slide.code_blocks.append((e, row))
                 pad = 4
             elif e.type == "codio":
                 effects.extend(_codio(self.screen, e, row))
@@ -140,12 +168,9 @@ def play(
         repeat=True,
         allow_int=False,
     ):
-        self.reset = [Slide(self, _reset(self.screen), 7, 0)]
+        self.reset = [Scene(_reset(self.screen))]
 
-        self.slides = [
-            Slide(self, self.get_effects(slide), slide.fg_color, slide.bg_color)
-            for slide in self.slides
-        ]
+        self.slides = [Slide(self, slide) for slide in self.slides]
 
         # Initialise the Screen for animation.
         self.screen.set_scenes(
@@ -189,6 +214,14 @@ def play(
 
                 a = time.time()
                 self.screen.draw_next_frame(repeat=repeat)
+
+                if self.current_slide < len(self.slides) and (
+                    code_blocks := self.slides[self.current_slide].code_blocks
+                ):
+                    for tpl in code_blocks:
+                        block_code, row = tpl
+                        render_code_block(self.screen, block_code, row)
+
                 if self.screen.has_resized():
                     if stop_on_resize:
                         self.screen._scenes[self.screen._scene_index].exit()

setup.py

@@ -17,6 +17,7 @@
     "Click>=7.0",
     "mistune>=2.0.0a4",
     "pyfiglet>=0.8.post1",
+    "Pygments>=2.10.0",
     "PyYAML>=5.3.1",
 ]
 dev_requires = ["black>=20.8b1", "Sphinx>=2.2.1"]