Function getApplicableRules

core/llm/rules/getSystemMessageWithRules.ts:276–326

(
  userMessage: UserChatMessage | ToolResultChatMessage | undefined,
  rules: RuleWithSource[],
  contextItems: ContextItemWithId[],
  rulePolicies: RulePolicies = {},
)

 * @returns List of applicable rules
 */
export const getApplicableRules = (
  userMessage: UserChatMessage | ToolResultChatMessage | undefined,
  rules: RuleWithSource[],
  contextItems: ContextItemWithId[],
  rulePolicies: RulePolicies = {},
): RuleWithSource[] => {
  // Get file paths from message and context for rule matching
  const filePathsFromMessage = userMessage
    ? extractPathsFromCodeBlocks(renderChatMessage(userMessage))
    : [];

  // Extract file paths from context items
  const filePathsFromContextItems = contextItems
    .filter((item) => item.uri?.type === "file" && item.uri?.value)
    .map((item) => item.uri!.value);

  // Combine file paths from both sources
  const allFilePaths = [...filePathsFromMessage, ...filePathsFromContextItems];

  // Create a map of file paths to their contents for pattern matching
  const fileContents: Record<string, string> = {};

  // Extract contents from context items with file URIs
  contextItems.forEach((item) => {
    if (item.uri?.type === "file" && item.uri?.value) {
      fileContents[item.uri.value] = item.content;
    }
  });

  // Extract contents from code blocks in the message for paths that don't have content yet
  if (userMessage) {
    const messageContent = renderChatMessage(userMessage);
    filePathsFromMessage.forEach((path) => {
      // Only extract content if we don't already have it from context items
      if (!fileContents[path]) {
        const blockContent = extractContentFromCodeBlock(messageContent, path);
        if (blockContent) {
          fileContents[path] = blockContent;
        }
      }
    });
  }

  // Apply shouldApplyRule to all rules - this will handle global rules, rule policies,
  // and path matching in a consistent way
  const applicableRules = rules.filter((rule) =>
    shouldApplyRule(rule, allFilePaths, rulePolicies, fileContents),
  );

  return applicableRules;
};

export function getRuleId(rule: RuleMetadata): string {
  return rule.slug ?? rule.sourceFile ?? rule.name ?? rule.source;