/**
 * $lookup with localField/foreignField and a pipeline holding a multi-input $rankFusion, from a
 * view: input pipelines after the first read the backing collection without the view's stages.
 *
 * @tags: [requires_fcv_90]
 */
const conn = MongoRunner.runMongod({setParameter: {internalQueryDisablePlanCache: true}});
const db = conn.getDB(jsTestName());

assert.commandWorked(db.c.insertMany([{_id: 1, a: 1, k: 1}, {_id: 2, a: 2, k: 1}]));
assert.commandWorked(db.l.insert({_id: 0, k: 1}));
// v keeps only a: 1, so _id 2 must never appear through it.
assert.commandWorked(db.createView("v", "c", [{$match: {a: 1}}]));

const rf2 = {$rankFusion: {input: {pipelines: {p1: [{$sort: {a: 1}}], p2: [{$sort: {a: -1}}]}}}};
const rf1 = {$rankFusion: {input: {pipelines: {p1: [{$sort: {a: 1}}]}}}};
const ids = (docs) => docs.map((d) => d._id).sort();
function run(label, fn) {
    const got = fn();
    jsTest.log.info("C run", {label, ids: got});
    return got;
}
const lookup = (spec) => ids(db.l.aggregate([{$lookup: Object.assign({from: "v", as: "r"}, spec)}]).toArray()[0].r);

const direct = run("aggregate on v with 2-input $rankFusion", () => ids(db.v.aggregate([rf2]).toArray()));
const union = run("$unionWith v with 2-input $rankFusion", () =>
    ids(db.l.aggregate([{$match: {_id: -1}}, {$unionWith: {coll: "v", pipeline: [rf2]}}]).toArray()));
const pipeOnly = run("$lookup pipeline-only from v with 2-input $rankFusion", () => lookup({pipeline: [rf2]}));
const lf1 = run("$lookup lf/ff from v with 1-input $rankFusion", () =>
    lookup({localField: "k", foreignField: "k", pipeline: [rf1]}));
const lf2 = run("$lookup lf/ff from v with 2-input $rankFusion", () =>
    lookup({localField: "k", foreignField: "k", pipeline: [rf2]}));

// Controls: every other access path applies v's $match to both inputs.
assert.eq(direct, [1], "aggregate on v");
assert.eq(union, [1], "$unionWith v");
assert.eq(pipeOnly, [1], "$lookup pipeline-only");
assert.eq(lf1, [1], "$lookup lf/ff, 1 input");
// Fails at ba06f31d06c: returns [1, 2]; the second input reads c without v's $match.
assert.eq(lf2, [1], "$lookup lf/ff, 2 inputs");

MongoRunner.stopMongod(conn);