Optimize get_command with O(1) lookup dictionary

.gitignore

@@ -9,6 +9,7 @@ target/
 # Claude Code local artifacts (not shared)
 .claude/settings.local.json
 .claude/sessions/
+.port_sessions/
 
 # Editor and OS artifacts
 *.swp

src/commands.py

@@ -1,13 +1,17 @@
 from __future__ import annotations
 
 import json
+from collections.abc import Mapping
 from dataclasses import dataclass
 from functools import lru_cache
 from pathlib import Path
+from types import MappingProxyType
 
 from .models import PortingBacklog, PortingModule
 
-SNAPSHOT_PATH = Path(__file__).resolve().parent / 'reference_data' / 'commands_snapshot.json'
+SNAPSHOT_PATH = (
+    Path(__file__).resolve().parent / "reference_data" / "commands_snapshot.json"
+)
 
 
 @dataclass(frozen=True)
@@ -24,10 +28,10 @@ def load_command_snapshot() -> tuple[PortingModule, ...]:
     raw_entries = json.loads(SNAPSHOT_PATH.read_text())
     return tuple(
         PortingModule(
-            name=entry['name'],
-            responsibility=entry['responsibility'],
-            source_hint=entry['source_hint'],
-            status='mirrored',
+            name=entry["name"],
+            responsibility=entry["responsibility"],
+            source_hint=entry["source_hint"],
+            status="mirrored",
         )
         for entry in raw_entries
     )
@@ -42,49 +46,78 @@ def built_in_command_names() -> frozenset[str]:
 
 
 def build_command_backlog() -> PortingBacklog:
-    return PortingBacklog(title='Command surface', modules=list(PORTED_COMMANDS))
+    return PortingBacklog(title="Command surface", modules=list(PORTED_COMMANDS))
 
 
 def command_names() -> list[str]:
     return [module.name for module in PORTED_COMMANDS]
 
 
-def get_command(name: str) -> PortingModule | None:
-    needle = name.lower()
+@lru_cache(maxsize=1)
+def _get_command_lookup() -> Mapping[str, PortingModule]:
+    lookup: dict[str, PortingModule] = {}
     for module in PORTED_COMMANDS:
-        if module.name.lower() == needle:
-            return module
-    return None
+        name_lower = module.name.lower()
+        if name_lower not in lookup:
+            lookup[name_lower] = module
+    return MappingProxyType(lookup)
 
 
-def get_commands(cwd: str | None = None, include_plugin_commands: bool = True, include_skill_commands: bool = True) -> tuple[PortingModule, ...]:
+def get_command(name: str) -> PortingModule | None:
+    return _get_command_lookup().get(name.lower())
+
+
+def get_commands(
+    include_plugin_commands: bool = True,
+    include_skill_commands: bool = True,
+) -> tuple[PortingModule, ...]:
     commands = list(PORTED_COMMANDS)
     if not include_plugin_commands:
-        commands = [module for module in commands if 'plugin' not in module.source_hint.lower()]
+        commands = [
+            module for module in commands if "plugin" not in module.source_hint.lower()
+        ]
     if not include_skill_commands:
-        commands = [module for module in commands if 'skills' not in module.source_hint.lower()]
+        commands = [
+            module for module in commands if "skills" not in module.source_hint.lower()
+        ]
     return tuple(commands)
 
 
 def find_commands(query: str, limit: int = 20) -> list[PortingModule]:
     needle = query.lower()
-    matches = [module for module in PORTED_COMMANDS if needle in module.name.lower() or needle in module.source_hint.lower()]
+    matches = [
+        module
+        for module in PORTED_COMMANDS
+        if needle in module.name.lower() or needle in module.source_hint.lower()
+    ]
     return matches[:limit]
 
 
-def execute_command(name: str, prompt: str = '') -> CommandExecution:
+def execute_command(name: str, prompt: str = "") -> CommandExecution:
     module = get_command(name)
     if module is None:
-        return CommandExecution(name=name, source_hint='', prompt=prompt, handled=False, message=f'Unknown mirrored command: {name}')
+        return CommandExecution(
+            name=name,
+            source_hint="",
+            prompt=prompt,
+            handled=False,
+            message=f"Unknown mirrored command: {name}",
+        )
     action = f"Mirrored command '{module.name}' from {module.source_hint} would handle prompt {prompt!r}."
-    return CommandExecution(name=module.name, source_hint=module.source_hint, prompt=prompt, handled=True, message=action)
+    return CommandExecution(
+        name=module.name,
+        source_hint=module.source_hint,
+        prompt=prompt,
+        handled=True,
+        message=action,
+    )
 
 
 def render_command_index(limit: int = 20, query: str | None = None) -> str:
     modules = find_commands(query, limit) if query else list(PORTED_COMMANDS[:limit])
-    lines = [f'Command entries: {len(PORTED_COMMANDS)}', '']
+    lines = [f"Command entries: {len(PORTED_COMMANDS)}", ""]
     if query:
-        lines.append(f'Filtered by: {query}')
-        lines.append('')
-    lines.extend(f'- {module.name} — {module.source_hint}' for module in modules)
-    return '\n'.join(lines)
+        lines.append(f"Filtered by: {query}")
+        lines.append("")
+    lines.extend(f"- {module.name} — {module.source_hint}" for module in modules)
+    return "\n".join(lines)