fb5-patch-pkg: an update build refuses a stage without node_modules or public/vendor when a base has them (a --no-install build would list every dependency file as removed and break each install it is applied to); the names no update deletes are split off in diffBases (left, named in the summary); test/update-package.test.js (9): the base-folder filters and the refusal

tools/package-update.mjs

@@ -190,13 +190,14 @@ export function readBase(source, { folder = 'Stronghold-Protocol', skip = () =>
 }
 
 /**
- * Compare the new full stage with the bases.
+ * Compare the new full stage with the bases. `removable(rel)`: false for a path no update deletes (it goes to `left`).
  * @param {Map<string, { size: number, sha256: string }>} next every file of the new version (the update files left out)
  * @param {{ version: string, files: Map<string, { size: number, sha256: string }> }[]} bases
- * @returns {{ ship: string[], removed: { path: string, sha256: string[] }[], caseOnly: string[],
+ * @param {{ removable?: (rel: string) => boolean }} [opts]
+ * @returns {{ ship: string[], removed: { path: string, sha256: string[] }[], caseOnly: string[], left: string[],
  *             perBase: { version: string, added: number, changed: number, unchanged: number, removed: number }[] }}
  */
-export function diffBases(next, bases) {
+export function diffBases(next, bases, { removable = () => true } = {}) {
   const ship = new Set();
   const perBase = [];
   for (const b of bases) {
@@ -211,10 +212,12 @@ export function diffBases(next, bases) {
   const lower = new Set([...next.keys()].map((f) => f.toLowerCase()));
   const removed = new Map();
   const caseOnly = new Set();
+  const left = new Set();
   for (const b of bases) {
     for (const [rel, d] of b.files) {
       if (next.has(rel)) continue;
       if (lower.has(rel.toLowerCase())) { caseOnly.add(rel); continue; }
+      if (!removable(rel)) { left.add(rel); continue; }
       if (!removed.has(rel)) removed.set(rel, new Set());
       removed.get(rel).add(d.sha256);
     }
@@ -223,6 +226,7 @@ export function diffBases(next, bases) {
     ship: [...ship].sort(),
     removed: [...removed.keys()].sort().map((rel) => ({ path: rel, sha256: [...removed.get(rel)].sort() })),
     caseOnly: [...caseOnly].sort(),
+    left: [...left].sort(),
     perBase,
   };
 }

tools/package.mjs

@@ -585,14 +585,19 @@ export function buildUpdate(root, p, bases, { out, install = true, force = false
   log(`comparing ${staged.length} files with ${bases.map((b) => `v${b.version}`).join(', ')} …`);
   const next = new Map();
   for (const f of staged) if (f !== MANIFEST_FILE) next.set(f, digestOf(full, f));
-  const diff = diffBases(next, bases);
+  // without npm ci the stage has no node_modules / public/vendor, and the update would delete the bases' copies
+  for (const lib of ['node_modules/', 'public/vendor/']) {
+    const inBase = bases.find((b) => [...b.files.keys()].some((f) => f.startsWith(lib)));
+    if (inBase && ![...next.keys()].some((f) => f.startsWith(lib))) {
+      throw new Error(`v${inBase.version} ships ${lib} but this build has none (--no-install?): an update built so would delete it from every install`);
+    }
+  }
   // a path no update deletes (a per-machine name such as node_modules/x/.env.example) stays behind, named in the summary
-  diff.left = diff.removed.filter((r) => removalProblem(r.path)).map((r) => r.path);
+  const diff = diffBases(next, bases, { removable: (rel) => !removalProblem(rel) });
   for (const rel of diff.left) {
     const bad = pathProblem(rel);
     if (bad) throw new Error(`a base ships ${rel}, which is ${bad}`);
   }
-  diff.removed = diff.removed.filter((r) => !removalProblem(r.path));
   for (const rel of diff.ship) copyInto(full, stage, rel);
   copyInto(full, stage, MANIFEST_FILE);
   const update = { app: p.version, from: bases.map((b) => b.version), files: new Map(diff.ship.map((f) => [f, next.get(f)])), removed: diff.removed };
@@ -632,7 +637,7 @@ export function formatUpdate(r, version) {
   const gone = r.diff.removed.map((x) => x.path);
   lines.push(`removed: ${gone.length} file(s)${gone.length ? ` (${gone.slice(0, 8).join(', ')}${gone.length > 8 ? ' …' : ''})` : ''}`);
   if (r.diff.caseOnly.length) lines.push(`not removed (a new file differs only in case): ${r.diff.caseOnly.join(', ')}`);
-  if (r.diff.left?.length) lines.push(`not removed (an update never deletes these names): ${r.diff.left.join(', ')}`);
+  if (r.diff.left.length) lines.push(`not removed (an update never deletes these names): ${r.diff.left.join(', ')}`);
   return lines.join('\n') + '\n';
 }