Enable error overlays

Author: johnslavik

Lib/_colorize.py

@@ -334,6 +334,7 @@ class LiveProfiler(ThemeSection):
 @dataclass(frozen=True, kw_only=True)
 class Syntax(ThemeSection):
     prompt: str = ANSIColors.BOLD_MAGENTA
+    error: str = ANSIColors.BOLD_RED
     keyword: str = ANSIColors.BOLD_BLUE
     keyword_constant: str = ANSIColors.BOLD_BLUE
     builtin: str = ANSIColors.CYAN

Lib/_pyrepl/reader.py

@@ -196,6 +196,7 @@ class Reader:
     ps3: str = "|.. "
     ps4: str = R"\__ "
     kill_ring: list[list[str]] = field(default_factory=list)
+    error_prefix: str = "! "
     msg: str = ""
     arg: int | None = None
     dirty: bool = False
@@ -641,7 +642,11 @@ def finish(self) -> None:
         pass
 
     def error(self, msg: str = "none") -> None:
-        self.msg = "! " + msg + " "
+        error_prefix = self.error_prefix
+        if self.can_colorize:
+            t = THEME()
+            error_prefix = f"{t.error}{error_prefix}{t.reset}"
+        self.msg = error_prefix + msg
         self.dirty = True
         self.console.beep()
 

Lib/_pyrepl/readline.py

@@ -124,9 +124,6 @@ def __post_init__(self) -> None:
         self.commands["backspace_dedent"] = backspace_dedent
         self.commands["backspace-dedent"] = backspace_dedent
 
-    def error(self, msg: str = "none") -> None:
-        pass  # don't show error messages by default
-
     def get_stem(self) -> str:
         b = self.buffer
         p = self.pos - 1