fix: suggest the nearest system or emulator name

scripts/common.py

@@ -350,6 +350,20 @@ def list_registered_platforms(
     return platforms
 
 
+def suggest_names(typed: list[str], available: list[str], listing_flag: str) -> str:
+    """The closest known names to what was typed, and how to see them all.
+
+    The hints showed the first ten or twenty names of the alphabet behind a
+    "..." whatever was typed: sony-playstaton listed 3do to apple-iie.
+    """
+    import difflib  # noqa: PLC0415
+
+    close = sorted({m for name in typed
+                    for m in difflib.get_close_matches(name, available, n=3, cutoff=0.6)})
+    hint = f"Did you mean: {', '.join(close)}? " if close else ""
+    return f"{hint}{listing_flag} lists all {len(available)}."
+
+
 def require_platform(name: str, platforms_dir: str = "platforms") -> None:
     """Exit with a usable message when no platform answers to a name.
 
@@ -1345,7 +1359,7 @@ def select_emulator_profiles(
             )
             raise ProfileSelectionError(
                 f"emulator '{name}' not found\n"
-                f"Available: {', '.join(available[:10])}..."
+                + suggest_names([name], available, "--list-emulators")
             )
         profile = all_profiles[name]
         kind = profile.get("type", "libretro")

scripts/generate_pack.py

@@ -30,6 +30,7 @@ from pathlib import Path
 sys.path.insert(0, os.path.dirname(__file__))
 from common import resolve_platform_cores as _platform_cores
 from common import (
+    suggest_names,
     require_platform,
     apply_target_overrides,
     archive_entry,
@@ -1646,10 +1647,8 @@ def generate_system_pack(
                 f"No emulators found for system(s): {', '.join(system_ids)}",
                 file=sys.stderr,
             )
-        print(
-            f"Available systems: {', '.join(sorted(all_systems)[:20])}...",
-            file=sys.stderr,
-        )
+        print(suggest_names(system_ids, sorted(all_systems), "--list-systems"),
+              file=sys.stderr)
         return None
 
     # Named like the platform's --system tag: one spelling of a system is

scripts/verify.py

@@ -34,6 +34,7 @@ import slots
 
 sys.path.insert(0, os.path.dirname(__file__))
 from common import (
+    suggest_names,
     require_platform,
     archive_entry,
     archive_members,
@@ -1849,10 +1850,8 @@ def verify_system(
                 f"No emulators found for system(s): {', '.join(system_ids)}",
                 file=sys.stderr,
             )
-        print(
-            f"Available systems: {', '.join(sorted(all_systems)[:20])}...",
-            file=sys.stderr,
-        )
+        print(suggest_names(system_ids, sorted(all_systems), "--list-systems"),
+              file=sys.stderr)
         sys.exit(1)
 
     return verify_emulator(