feat(javascript): retain queryable static route inventories (#6019)

src/domain/javascript/javascriptRoutePaths.ts

@@ -0,0 +1,92 @@
+/** URL route syntax, independent of filesystem path normalization. */
+export const routePath = (
+  value: string,
+  options: { relative?: boolean; navigation?: boolean } = {},
+): string | undefined => {
+  const end = options.navigation ? value.search(/[?#]/u) : -1;
+  const path = end < 0 ? value : value.slice(0, end);
+  if (!path || /[\u0000-\u0020\u007f\\]/u.test(path) || path.startsWith("//"))
+    return;
+  if (!path.startsWith("/") && !options.relative) return;
+  if (/^[a-z][a-z0-9+.-]*:/iu.test(path)) return;
+  return path.startsWith("/") ? path : `/${path}`;
+};
+
+export type NextAppRoutePath =
+  | { readonly kind: "known"; readonly path: string }
+  | { readonly kind: "unknown"; readonly reason: string };
+
+/** Classify a page filename without treating missing routing context as absence. */
+export const classifyNextAppRoutePath = (
+  raw: string,
+): NextAppRoutePath | undefined => {
+  if (raw.includes("\\")) return;
+  let value = raw;
+  if (raw.includes("://")) {
+    try {
+      value = new URL(raw).pathname;
+    } catch {
+      return;
+    }
+  }
+  // A deployment prefix may itself contain an `app` segment. Only the chunk
+  // path following Next's asset boundary can describe an App Router module.
+  const assetRoot = value.indexOf("/_next/");
+  if (assetRoot >= 0) value = value.slice(assetRoot + "/_next/".length);
+  const match =
+    /(?:^|\/)app\/(?:(.*?)\/)?page(?:-([^/?#]+)\.js|\.(?:[cm]?jsx?|tsx?)|)(?:[?#].*)?$/u.exec(
+      value,
+    );
+  if (!match) return;
+  if (match[2] !== undefined && !/(?:^|\/)static\/chunks\/app\//u.test(value))
+    return;
+  const encodedSegments = (match[1] ?? "").split("/");
+  // A private folder excludes the whole page, including intercepted ancestors.
+  // Test before decoding: %5F names are public URLs.
+  if (encodedSegments.some((segment) => segment.startsWith("_"))) return;
+  const segments: string[] = [];
+  for (const encoded of encodedSegments) {
+    let segment: string;
+    try {
+      segment = decodeURIComponent(encoded);
+    } catch {
+      return;
+    }
+    if (/^\([^)]*\)$/u.test(segment) || segment.startsWith("@")) continue;
+    // Intercepted routes need a parent routing context that a filename does not establish.
+    if (segment.startsWith("("))
+      return {
+        kind: "unknown",
+        reason:
+          "An intercepted Next page route requires parent routing context unavailable from its filename.",
+      };
+    if (segment.includes("/") || segment === "." || segment === "..") return;
+    const optional = /^\[\[\.\.\.([^\]]+)\]\]$/u.exec(segment);
+    const catchAll = /^\[\.\.\.([^\]]+)\]$/u.exec(segment);
+    const parameter = /^\[([^\]]+)\]$/u.exec(segment);
+    segments.push(
+      optional
+        ? `:${optional[1]}*`
+        : catchAll
+          ? `:${catchAll[1]}+`
+          : parameter
+            ? `:${parameter[1]}`
+            : segment,
+    );
+  }
+  const path = routePath(`/${segments.filter(Boolean).join("/")}`);
+  return path === undefined ? undefined : { kind: "known", path };
+};
+
+export const nextScriptBasePath = (source: string): string | undefined => {
+  let path = source;
+  if (/^https?:\/\//iu.test(source)) {
+    try {
+      path = new URL(source).pathname;
+    } catch {
+      return;
+    }
+  } else if (!source.startsWith("/")) return;
+  const at = path.indexOf("/_next/");
+  return at < 0 ? undefined : path.slice(0, at);
+};