feat: show source lines in the traceback

src/python/app/console.py

@@ -1,11 +1,16 @@
 import builtins
+import sys
 from collections import ChainMap
+from contextlib import suppress
 from functools import cached_property
+from pathlib import Path
+from tempfile import TemporaryDirectory
 from typing import TYPE_CHECKING
 
 from pyodide.console import ConsoleFuture, PyodideConsole
 
 from .utils.bridge import js_api
+from .utils.patches import patch_linecache
 
 
 class ConsoleGlobals(ChainMap, dict):  # type: ignore
@@ -30,6 +35,34 @@ async def get_repr(self):
             return repr(res)
 
 
+class EnhancedConsole(PyodideConsole):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        with TemporaryDirectory(delete=False) as tempdir:
+            sys.path.append(tempdir)
+            self.fake_file = Path(tempdir) / self.filename
+
+        self.line_offset = 0
+
+    def __del__(self):
+        with suppress(Exception):
+            sys.path.remove(str(self.fake_file.parent))
+
+    def _append_source_file(self, source: str):
+        source += "\n"
+        self.line_offset += source.count("\n")
+        with self.fake_file.open("a+", encoding="utf-8") as file:
+            file.write(source)
+
+    def runsource(self, source: str, filename="<console>"):
+        patch_linecache()
+
+        fake_source = "\n" * self.line_offset + source
+        self._append_source_file(source)
+        return super().runsource(fake_source, filename)
+
+
 class Console:
     @cached_property
     def builtins_layer(self):
@@ -55,7 +88,7 @@ def __getitem__(self, key: str):
 
             context.maps.append(Proxy())
 
-        return PyodideConsole(context)
+        return EnhancedConsole(context)
 
     @js_api
     def complete(self, source: str):

src/python/app/utils/patches.py

@@ -1,8 +1,17 @@
 from functools import cache
+from inspect import getsource
 
 from .lock import with_lock
 
 
+@cache
+def patch_linecache():
+    import linecache
+
+    source = getsource(linecache).replace(" or (filename.startswith('<') and filename.endswith('>'))", "", 1)
+    exec(source, linecache.__dict__)
+
+
 @cache
 def patch_console():
     from pyodide.console import PyodideConsole