fix(convert): use hash to restrict the length of new filenames (#124)

Closes #123

example.py

@@ -32,6 +32,24 @@ class BasicExample(Slide):
         self.pause()  # Waits user to press continue to go to the next slide
 
 
+class TestFileTooLong(Slide):
+    """This is used to check against solution for issue #123."""
+
+    def construct(self):
+        import random
+
+        circle = Circle(radius=3, color=BLUE)
+        dot = Dot()
+        self.play(GrowFromCenter(circle), run_time=0.1)
+
+        for _ in range(30):
+            direction = (random.random() - 0.5) * LEFT + (random.random() - 0.5) * UP
+            self.play(dot.animate.move_to(direction), run_time=0.1)
+            self.play(dot.animate.move_to(ORIGIN), run_time=0.1)
+
+        self.pause()
+
+
 class ConvertExample(Slide):
     """WARNING: this example does not seem to work with ManimGL."""
 

manim_slides/config.py

@@ -1,3 +1,4 @@
+import hashlib
 import os
 import shutil
 import subprocess
@@ -15,11 +16,18 @@ def merge_basenames(files: List[str]) -> str:
     """
     Merge multiple filenames by concatenating basenames.
     """
+    logger.info(f"Generating a new filename for animations: {files}")
 
     dirname = os.path.dirname(files[0])
     _, ext = os.path.splitext(files[0])
 
-    basename = "_".join(os.path.splitext(os.path.basename(file))[0] for file in files)
+    basenames = (os.path.splitext(os.path.basename(file))[0] for file in files)
+
+    basenames_str = ",".join(f"{len(b)}:{b}" for b in basenames)
+
+    # We use hashes to prevent too-long filenames, see issue #123:
+    # https://github.com/jeertmans/manim-slides/issues/123
+    basename = hashlib.sha256(basenames_str.encode()).hexdigest()
 
     return os.path.join(dirname, basename + ext)