♻️ allow value type to be undefined

Author: momocow

lib/features/render-headers.ts

@@ -81,10 +81,13 @@ export class RenderHeaders extends Feature<RenderHeadersOptions> {
 
   protected renderTag(tag: TagType, value: ValueType): string[][] {
     if (Array.isArray(value)) {
-      return value.map((v) => [`// @${tag}`, v]);
+      return value.map((v) => [`// @${tag}`, v ?? '']);
     }
     if (typeof value === 'object') {
-      return Object.entries(value).map(([k, v]) => [`// @${tag}`, `${k} ${v}`]);
+      return Object.entries(value).map(([k, v]) => [
+        `// @${tag}`,
+        `${k} ${v ?? ''}`,
+      ]);
     }
     if (typeof value === 'string') {
       return [[`// @${tag}`, value]];

lib/features/ssri.ts

@@ -196,9 +196,9 @@ export class ProcessSSRI extends Feature<SSRIOptions> {
     const urls: string[] = [];
 
     if (headers.require !== undefined) {
-      const requireURLs = Array.isArray(headers.require)
-        ? headers.require
-        : [headers.require];
+      const requireURLs = (
+        Array.isArray(headers.require) ? headers.require : [headers.require]
+      ).filter((url): url is string => typeof url === 'string');
 
       for (const urlStr of requireURLs) {
         const url = this.parseURL(urlStr);
@@ -209,7 +209,9 @@ export class ProcessSSRI extends Feature<SSRIOptions> {
     }
 
     if (headers.resource !== undefined) {
-      for (const urlStr of Object.values(headers.resource)) {
+      for (const urlStr of Object.values(headers.resource).filter(
+        (url): url is string => typeof url === 'string',
+      )) {
         const url = this.parseURL(urlStr);
         if (this.filterURL(url, 'resource', options)) {
           urls.push(this.stringifyURL(url));
@@ -316,20 +318,21 @@ export class ProcessSSRI extends Feature<SSRIOptions> {
 
     if (headers.require !== undefined) {
       if (Array.isArray(headers.require)) {
-        headersProps.require = headers.require.map((url) =>
-          this.updateURL(url, ssriLock),
-        );
+        headersProps.require = headers.require
+          .filter((url): url is string => typeof url === 'string')
+          .map((url) => this.updateURL(url, ssriLock));
       } else {
         headersProps.require = this.updateURL(headers.require, ssriLock);
       }
     }
 
     if (headers.resource !== undefined) {
       headersProps.resource = Object.fromEntries(
-        Object.entries(headers.resource).map(([name, url]) => [
-          name,
-          this.updateURL(url, ssriLock),
-        ]),
+        Object.entries(headers.resource)
+          .filter(
+            (entry): entry is [string, string] => typeof entry[1] === 'string',
+          )
+          .map(([name, url]) => [name, this.updateURL(url, ssriLock)]),
       );
     }
 

lib/types.ts

@@ -14,19 +14,19 @@ import {
   ValidateHeadersOptions,
 } from './features';
 
+export type SingleValue = string | undefined;
+export type MultiValue = SingleValue | SingleValue[];
+export type NamedValue = Record<string, SingleValue>;
+export type SwitchValue = boolean;
+
 export type TagType = string;
 export type ValueType =
-  | Record<string, string>
-  | string[]
-  | string
-  | boolean
+  | NamedValue
+  | MultiValue
+  | SingleValue
+  | SwitchValue
   | undefined;
 
-export type SingleValue = string;
-export type MultiValue = string | string[];
-export type NamedValue = Record<string, string>;
-export type SwitchValue = boolean;
-
 export enum RunAtValue {
   DocumentStart = 'document-start',
   DocumentBody = 'document-body',