// Cannot implicitly shard accessed collections because queries on a sharded collection are not
// able to be covered when they aren't on the shard key since the document needs to be fetched in
// order to apply the SHARDING_FILTER stage.
// @tags: [
//   assumes_unsharded_collection,
// ]

// Simple covered index query test

// Include helpers for analyzing explain output.
import {isIndexOnly} from "jstests/libs/query/analyze_plan.js";

var coll = db.getCollection("covered_simple_1");
coll.drop();
for (let i = 0; i < 10; i++) {
    coll.insert({foo: i});
}
for (let i = 0; i < 10; i++) {
    coll.insert({foo: i});
}
for (let i = 0; i < 5; i++) {
    coll.insert({bar: i});
}
coll.insert({foo: "string"});
coll.insert({foo: {bar: 1}});
coll.insert({foo: null});
coll.createIndex({foo: 1});

// Test equality with int value
var plan = coll.find({foo: 1}, {foo: 1, _id: 0}).hint({foo: 1}).explain("executionStats");
assert(isIndexOnly(db, plan.queryPlanner.winningPlan),
       "simple.1.1 - indexOnly should be true on covered query");
assert.eq(0,
          plan.executionStats.totalDocsExamined,
          "simple.1.1 - docs examined should be 0 for covered query");

// Test equality with string value
var plan = coll.find({foo: "string"}, {foo: 1, _id: 0}).hint({foo: 1}).explain("executionStats");
assert(isIndexOnly(db, plan.queryPlanner.winningPlan),
       "simple.1.2 - indexOnly should be true on covered query");
assert.eq(0,
          plan.executionStats.totalDocsExamined,
          "simple.1.2 - docs examined should be 0 for covered query");

// Test equality with doc value
var plan = coll.find({foo: {bar: 1}}, {foo: 1, _id: 0}).hint({foo: 1}).explain("executionStats");
assert(isIndexOnly(db, plan.queryPlanner.winningPlan),
       "simple.1.3 - indexOnly should be true on covered query");
assert.eq(0,
          plan.executionStats.totalDocsExamined,
          "simple.1.3 - docs examined should be 0 for covered query");

// Test no query
if (!TestData.isHintsToQuerySettingsSuite) {
    // This guard excludes this test case from being run on the cursor_hints_to_query_settings
    // suite. The suite replaces cursor hints with query settings. Query settings do not force
    // indexes, and therefore empty filter will result in collection scans.
    var plan = coll.find({}, {foo: 1, _id: 0}).hint({foo: 1}).explain("executionStats");
    assert(isIndexOnly(db, plan.queryPlanner.winningPlan),
           "simple.1.4 - indexOnly should be true on covered query");
    assert.eq(0,
              plan.executionStats.totalDocsExamined,
              "simple.1.4 - docs examined should be 0 for covered query");
}

// Test range query
var plan =
    coll.find({foo: {$gt: 2, $lt: 6}}, {foo: 1, _id: 0}).hint({foo: 1}).explain("executionStats");
assert(isIndexOnly(db, plan.queryPlanner.winningPlan),
       "simple.1.5 - indexOnly should be true on covered query");
assert.eq(0,
          plan.executionStats.totalDocsExamined,
          "simple.1.5 - docs examined should be 0 for covered query");

// Test in query
var plan =
    coll.find({foo: {$in: [5, 8]}}, {foo: 1, _id: 0}).hint({foo: 1}).explain("executionStats");
assert(isIndexOnly(db, plan.queryPlanner.winningPlan),
       "simple.1.6 - indexOnly should be true on covered query");
assert.eq(0,
          plan.executionStats.totalDocsExamined,
          "simple.1.6 - docs examined should be 0 for covered query");

// Test no return
var plan = coll.find({foo: "2"}, {foo: 1, _id: 0}).hint({foo: 1}).explain("executionStats");
assert(isIndexOnly(db, plan.queryPlanner.winningPlan),
       "simple.1.7 - indexOnly should be true on covered query");
assert.eq(0,
          plan.executionStats.totalDocsExamined,
          "simple.1.7 - nscannedObjects should be 0 for covered query");

print('all tests pass');
