The engine-version check ignores manifest changes npm never publishes

scripts/check-engine-version.mjs

@@ -29,6 +29,23 @@ function isNotFoundError(error) {
 
 const rootDir = dirname(dirname(fileURLToPath(import.meta.url)));
 
+const ENGINE_MANIFEST = "packages/cli-engine/package.json";
+
+/**
+ * Whether a manifest change alters what npm publishes. devDependencies
+ * never ship in the tarball — the release version sweep rewrites the
+ * engine's `@repo/*` devDependencies on every bump, and that must not
+ * read as "the engine changed".
+ *
+ * @param {Record<string, unknown>} base
+ * @param {Record<string, unknown>} head
+ * @returns {boolean}
+ */
+export function manifestChangeShips(base, head) {
+  const shipped = ({ devDependencies: _dev, ...rest }) => rest;
+  return JSON.stringify(shipped(base)) !== JSON.stringify(shipped(head));
+}
+
 /**
  * @param {{ changedFiles: readonly string[], engineVersion: string, versionOnRegistry: boolean }} input
  * @returns {string | null} the failure message, or null when the change is fine
@@ -66,7 +83,21 @@ async function main() {
     ["diff", "--name-only", mergeBase.trim(), "HEAD"],
     { cwd: rootDir },
   );
-  const changedFiles = diff.split("\n").filter(Boolean);
+  let changedFiles = diff.split("\n").filter(Boolean);
+
+  if (changedFiles.includes(ENGINE_MANIFEST)) {
+    const { stdout: baseManifest } = await execFileAsync(
+      "git",
+      ["show", `${mergeBase.trim()}:${ENGINE_MANIFEST}`],
+      { cwd: rootDir },
+    );
+    const headManifest = readFileSync(join(rootDir, ENGINE_MANIFEST), "utf-8");
+    if (
+      !manifestChangeShips(JSON.parse(baseManifest), JSON.parse(headManifest))
+    ) {
+      changedFiles = changedFiles.filter((file) => file !== ENGINE_MANIFEST);
+    }
+  }
 
   const manifest = JSON.parse(
     readFileSync(join(rootDir, "packages/cli-engine/package.json"), "utf-8"),

scripts/check-engine-version.test.mjs

@@ -1,6 +1,9 @@
 import assert from "node:assert/strict";
 import { describe, it } from "node:test";
-import { engineBumpVerdict } from "./check-engine-version.mjs";
+import {
+  engineBumpVerdict,
+  manifestChangeShips,
+} from "./check-engine-version.mjs";
 
 const NAMES_THE_STALE_VERSION = /0\.1\.1/;
 const NAMES_THE_BUMP_COMMAND = /bump-cli-engine-version/;
@@ -46,3 +49,39 @@ describe("engineBumpVerdict", () => {
     assert.equal(verdict, null);
   });
 });
+
+describe("manifestChangeShips", () => {
+  const base = {
+    name: "@prisma/cli-engine",
+    version: "0.2.0",
+    dependencies: { colorette: "^2.0.20" },
+    devDependencies: { "@repo/tsconfig": "workspace:8.0.0-rc.4" },
+  };
+
+  it("a devDependencies-only change does not ship", () => {
+    const head = {
+      ...base,
+      devDependencies: { "@repo/tsconfig": "workspace:8.0.0-rc.5" },
+    };
+    assert.equal(manifestChangeShips(base, head), false);
+  });
+
+  it("a version change ships", () => {
+    assert.equal(
+      manifestChangeShips(base, { ...base, version: "0.2.1" }),
+      true,
+    );
+  });
+
+  it("a dependencies change ships", () => {
+    const head = { ...base, dependencies: { colorette: "^2.1.0" } };
+    assert.equal(manifestChangeShips(base, head), true);
+  });
+
+  it("an added field ships", () => {
+    assert.equal(
+      manifestChangeShips(base, { ...base, sideEffects: false }),
+      true,
+    );
+  });
+});