Function prepareIfConditionMatcher

src/utils/hooks.ts:1390–1421

* Prepare a matcher for hook `if` conditions. Expensive work (tool lookup, * Zod validation, tree-sitter parsing for Bash) happens once here; the * returned closure is called per hook. Returns undefined for non-tool events.

(
  hookInput: HookInput,
  tools: Tools | undefined,
)

 * returned closure is called per hook. Returns undefined for non-tool events.
 */
async function prepareIfConditionMatcher(
  hookInput: HookInput,
  tools: Tools | undefined,
): Promise<IfConditionMatcher | undefined> {
  if (
    hookInput.hook_event_name !== 'PreToolUse' &&
    hookInput.hook_event_name !== 'PostToolUse' &&
    hookInput.hook_event_name !== 'PostToolUseFailure' &&
    hookInput.hook_event_name !== 'PermissionRequest'
  ) {
    return undefined
  }

  const toolName = normalizeLegacyToolName(hookInput.tool_name)
  const tool = tools && findToolByName(tools, hookInput.tool_name)
  const input = tool?.inputSchema.safeParse(hookInput.tool_input)
  const patternMatcher =
    input?.success && tool?.preparePermissionMatcher
      ? await tool.preparePermissionMatcher(input.data)
      : undefined

  return ifCondition => {
    const parsed = permissionRuleValueFromString(ifCondition)
    if (normalizeLegacyToolName(parsed.toolName) !== toolName) {
      return false
    }
    if (!parsed.ruleContent) {
      return true
    }
    return patternMatcher ? patternMatcher(parsed.ruleContent) : false
  }
}

type FunctionHookMatcher = {
  matcher: string