fix(gatsby-plugin-sitemap): remove splice for default filter

packages/gatsby-plugin-sitemap/src/__tests__/internals.js

@@ -97,4 +97,29 @@ describe(`gatsby-plugin-sitemap internals tests`, () => {
 
     expect(results).toMatchSnapshot()
   })
+
+  it(`pageFilter should filter correctly on consecutive runs`, () => {
+    const allPages = [
+      { path: `/to/keep/1` },
+      { path: `/to/keep/2` },
+      { path: `/404.html` },
+    ]
+    const filterPages = jest.fn()
+
+    const { filteredPages } = pageFilter({
+      allPages,
+      filterPages,
+      excludes: [],
+    })
+    expect(filteredPages).toHaveLength(2)
+    expect(filteredPages).not.toContainEqual({ path: `/404.html` })
+
+    const { filteredPages: filteredPages2 } = pageFilter({
+      allPages,
+      filterPages,
+      excludes: [],
+    })
+    expect(filteredPages2).toHaveLength(2)
+    expect(filteredPages2).not.toContainEqual({ path: `/404.html` })
+  })
 })

packages/gatsby-plugin-sitemap/src/internals.js

@@ -161,19 +161,14 @@ export function pageFilter({ allPages, filterPages, excludes }) {
 
   // TODO we should optimize these loops
   const filteredPages = allPages.filter(page => {
-    const defaultFilterMatches = defaultExcludes.some((exclude, i, arr) => {
+    const defaultFilterMatches = defaultExcludes.some(exclude => {
       try {
         const doesMatch = defaultFilterPages(page, exclude, {
           minimatch,
           withoutTrailingSlash,
           resolvePagePath,
         })
 
-        // default excludes can only be found once, so remove them from the arr once excluded
-        if (doesMatch) {
-          arr.splice(i, 1)
-        }
-
         return doesMatch
       } catch {
         throw new Error(`${REPORTER_PREFIX} Error in default page filter`)