fix(javascript): bind Next page admission to source context

src/application/javascript/JavaScriptNextAppContext.test.ts

@@ -0,0 +1,93 @@
+import { expect, it } from "vitest";
+
+import type { JavaScriptArtifactFile } from "../../domain/javascript/javascriptArtifactFiles.js";
+import { JavaScriptJsonDocuments } from "./JavaScriptJsonDocuments.js";
+import { createJavaScriptNextAppContext } from "./JavaScriptNextAppContext.js";
+
+const file = (path: string, text = ""): JavaScriptArtifactFile => ({
+  path,
+  container_sha256: "a".repeat(64),
+  sha256: "b".repeat(64),
+  bytes: Buffer.byteLength(text),
+  inventory_artifact_id: `art_${"b".repeat(64)}`,
+  kind: path.endsWith("package.json") ? "package-json" : "javascript",
+  unpacked: false,
+  text: { included: true, value: text },
+});
+
+it("uses the nearest declared Next package and root directory precedence", () => {
+  const files = [
+    file("package.json", '{"dependencies":{"next":"16.4.2"}}'),
+    file("app/page.js"),
+    file("src/app/control/page.js"),
+    file("pages/app/page.js"),
+    file("components/app/page.js"),
+    file("node_modules/ordinary/package.json", '{"name":"ordinary"}'),
+    file("node_modules/ordinary/app/page.js"),
+  ];
+  const context = createJavaScriptNextAppContext(
+    files,
+    new JavaScriptJsonDocuments(),
+    new Set([
+      "app",
+      "src/app",
+      "pages",
+      "components/app",
+      "node_modules/ordinary/app",
+    ]),
+  );
+  expect(context(files[1]!)).toMatchObject({
+    kind: "app-directory",
+    directory: "app",
+    package: { path: "package.json" },
+  });
+  for (const source of files.slice(2, 5))
+    expect(context(source).kind).toBe("outside-app-directory");
+  expect(context(files[6]!)).toMatchObject({
+    kind: "unknown",
+    package: { path: "node_modules/ordinary/package.json" },
+  });
+});
+
+it("keeps default compiled output under its declared package and unrelated chunk-like paths unknown", () => {
+  const manifest = file("package.json", '{"dependencies":{"next":"16.4.2"}}');
+  const chunk = file(".next/static/chunks/app/build/page-abc.js");
+  const context = createJavaScriptNextAppContext(
+    [manifest, chunk],
+    new JavaScriptJsonDocuments(),
+    new Set(),
+  );
+  expect(context(chunk)).toMatchObject({
+    kind: "compiled-directory",
+    directory: ".next/static/chunks/app",
+  });
+  expect(
+    createJavaScriptNextAppContext(
+      [chunk],
+      new JavaScriptJsonDocuments(),
+      new Set(),
+    )(chunk),
+  ).toMatchObject({ kind: "unknown" });
+});
+
+it("supports src/app only when app is not inventoried and retains missing framework identity", () => {
+  const manifest = file(
+    "package.json",
+    '{"devDependencies":{"next":"16.4.2"}}',
+  );
+  const page = file("src/app/control/page.js");
+  expect(
+    createJavaScriptNextAppContext(
+      [manifest, page],
+      new JavaScriptJsonDocuments(),
+      new Set(["src/app"]),
+    )(page),
+  ).toMatchObject({ kind: "app-directory", directory: "src/app" });
+  expect(
+    createJavaScriptNextAppContext(
+      [page],
+      new JavaScriptJsonDocuments(),
+      new Set(["src/app"]),
+    )(page),
+  ).toMatchObject({ kind: "unknown", package: null });
+});