/**
 *    Copyright (C) 2013 10gen Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */


#include "mongo/db/ops/modifier_set.h"

#include <cstdint>

#include "mongo/base/status.h"
#include "mongo/base/string_data.h"
#include "mongo/bson/mutable/algorithm.h"
#include "mongo/bson/mutable/document.h"
#include "mongo/bson/mutable/mutable_bson_test_utils.h"
#include "mongo/db/jsobj.h"
#include "mongo/db/json.h"
#include "mongo/db/ops/log_builder.h"
#include "mongo/unittest/unittest.h"

namespace {

using mongo::BSONObj;
using mongo::fromjson;
using mongo::LogBuilder;
using mongo::ModifierInterface;
using mongo::NumberInt;
using mongo::ModifierSet;
using mongo::Status;
using mongo::StringData;
using mongo::mutablebson::ConstElement;
using mongo::mutablebson::countChildren;
using mongo::mutablebson::Document;
using mongo::mutablebson::Element;

/** Helper to build and manipulate a $set mod. */
class Mod {
public:
    Mod() : _mod() {}

    explicit Mod(BSONObj modObj, bool fromRepl = false)
        : _mod(mongoutils::str::equals(modObj.firstElement().fieldName(), "$setOnInsert")
                   ? ModifierSet::SET_ON_INSERT
                   : ModifierSet::SET_NORMAL) {
        _modObj = modObj;
        StringData modName = modObj.firstElement().fieldName();
        ASSERT_OK(_mod.init(_modObj[modName].embeddedObject().firstElement(),
                            !fromRepl ? ModifierInterface::Options::normal()
                                      : ModifierInterface::Options::fromRepl()));
    }

    Status prepare(Element root, StringData matchedField, ModifierInterface::ExecInfo* execInfo) {
        return _mod.prepare(root, matchedField, execInfo);
    }

    Status apply() const {
        return _mod.apply();
    }

    Status log(LogBuilder* logBuilder) const {
        return _mod.log(logBuilder);
    }

    ModifierSet& mod() {
        return _mod;
    }

private:
    ModifierSet _mod;
    BSONObj _modObj;
};

//
// Init tests
//

TEST(Init, EmptyOperation) {
    BSONObj modObj = fromjson("{$set: {}}");
    ModifierSet mod;
    ASSERT_NOT_OK(mod.init(modObj["$set"].embeddedObject().firstElement(),
                           ModifierInterface::Options::normal()));
}

//
// Simple Mods
//

TEST(SimpleMod, PrepareNoOp) {
    Document doc(fromjson("{a: 2}"));
    Mod setMod(fromjson("{$set: {a: 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
    ASSERT_TRUE(execInfo.noOp);
}

TEST(SimpleMod, PrepareNotNoOp) {
    Document doc(fromjson("{a: NumberInt(2)}"));
    Mod setMod(fromjson("{$set: {a: NumberLong(2)}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
    ASSERT_FALSE(execInfo.noOp);
}

TEST(SimpleMod, PrepareIdentityOpOnDeserializedIsNotANoOp) {
    Document doc(fromjson("{a: { b: NumberInt(0)}}"));

    // Apply a mutation to the document that will make it non-serialized.
    doc.root()["a"]["b"].setValueInt(2);

    // Apply an op that would be a no-op.
    Mod setMod(fromjson("{$set: {a: {b : NumberInt(2)}}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
    ASSERT_FALSE(execInfo.noOp);
}

TEST(SimpleMod, PrepareSetOnInsert) {
    Document doc(fromjson("{a: 1}"));
    Mod setMod(fromjson("{$setOnInsert: {a: 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
    ASSERT_FALSE(execInfo.noOp);
    ASSERT_EQUALS(execInfo.context, ModifierInterface::ExecInfo::INSERT_CONTEXT);
}

TEST(SimpleMod, PrepareApplyEmptyDocument) {
    Document doc(fromjson("{}"));
    Mod setMod(fromjson("{$set: {a: 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: 2}"), doc);
}

TEST(SimpleMod, PrepareApplyInPlace) {
    Document doc(fromjson("{a: 1}"));
    Mod setMod(fromjson("{$set: {a: 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_TRUE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: 2}"), doc);
}

TEST(SimpleMod, PrepareApplyOverridePath) {
    Document doc(fromjson("{a: {b: 1}}"));
    Mod setMod(fromjson("{$set: {a: 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: 2}"), doc);
}

TEST(SimpleMod, PrepareApplyChangeType) {
    Document doc(fromjson("{a: 'str'}"));
    Mod setMod(fromjson("{$set: {a: 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: 2}"), doc);
}

TEST(SimpleMod, PrepareApplyNewPath) {
    Document doc(fromjson("{b: 1}"));
    Mod setMod(fromjson("{$set: {a: 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{b: 1, a: 2}"), doc);
}

TEST(SimpleMod, LogNormal) {
    BSONObj obj = fromjson("{a: 1}");
    Mod setMod(fromjson("{$set: {a: 2}}"));

    Document doc(obj);
    ModifierInterface::ExecInfo dummy;
    ASSERT_OK(setMod.prepare(doc.root(), "", &dummy));

    Document logDoc;
    LogBuilder logBuilder(logDoc.root());
    ASSERT_OK(setMod.log(&logBuilder));
    ASSERT_EQUALS(countChildren(logDoc.root()), 1u);
    ASSERT_EQUALS(fromjson("{$set: {a: 2}}"), logDoc);
}

//
// Simple dotted mod
//

TEST(DottedMod, PrepareNoOp) {
    Document doc(fromjson("{a: {b: 2}}"));
    Mod setMod(fromjson("{$set: {'a.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
    ASSERT_TRUE(execInfo.noOp);
}

TEST(DottedMod, PrepareNotNoOp) {
    Document doc(fromjson("{a: {b: NumberLong(2)}}"));
    Mod setMod(fromjson("{$set: {'a.b': NumberInt(2)}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
    ASSERT_FALSE(execInfo.noOp);
}

TEST(DottedMod, PreparePathNotViable) {
    Document doc(fromjson("{a:1}"));
    Mod setMod(fromjson("{$set: {'a.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_NOT_OK(setMod.prepare(doc.root(), "", &execInfo));
}

TEST(DottedMod, PreparePathNotViableArrray) {
    Document doc(fromjson("{a:[{b:1}]}"));
    Mod setMod(fromjson("{$set: {'a.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_NOT_OK(setMod.prepare(doc.root(), "", &execInfo));
}

TEST(DottedMod, PrepareApplyInPlace) {
    Document doc(fromjson("{a: {b: 1}}"));
    Mod setMod(fromjson("{$set: {'a.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_TRUE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {b: 2}}"), doc);
}

TEST(DottedMod, PrepareApplyChangeType) {
    Document doc(fromjson("{a: {b: 'str'}}"));
    Mod setMod(fromjson("{$set: {'a.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {b: 2}}"), doc);
}

TEST(DottedMod, PrepareApplyChangePath) {
    Document doc(fromjson("{a: {b: {c: 1}}}"));
    Mod setMod(fromjson("{$set: {'a.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {b: 2}}"), doc);
}

TEST(DottedMod, PrepareApplyExtendPath) {
    Document doc(fromjson("{a: {c: 1}}"));
    Mod setMod(fromjson("{$set: {'a.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {c: 1, b: 2}}"), doc);
}

TEST(DottedMod, PrepareApplyNewPath) {
    Document doc(fromjson("{c: 1}"));
    Mod setMod(fromjson("{$set: {'a.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{c: 1, a: {b: 2}}"), doc);
}

TEST(DottedMod, PrepareApplyEmptyDoc) {
    Document doc(fromjson("{}"));
    Mod setMod(fromjson("{$set: {'a.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {b: 2}}"), doc);
}

TEST(DottedMod, PrepareApplyFieldWithDot) {
    Document doc(fromjson("{'a.b':4}"));
    Mod setMod(fromjson("{$set: {'a.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{'a.b':4, a: {b: 2}}"), doc);
}

//
// Indexed mod
//

TEST(IndexedMod, PrepareNoOp) {
    Document doc(fromjson("{a: [{b: 0},{b: 1},{b: 2}]}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_TRUE(execInfo.noOp);
}

TEST(IndexedMod, PrepareNotNoOp) {
    Document doc(fromjson("{a: [{b: 0},{b: 1},{b: 2.0}]}"));
    Mod setMod(fromjson("{$set: {'a.2.b': NumberInt(2)}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_FALSE(execInfo.noOp);
}

TEST(IndexedMod, PrepareNonViablePath) {
    Document doc(fromjson("{a: 0}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_NOT_OK(setMod.prepare(doc.root(), "", &execInfo));
}

TEST(IndexedMod, PrepareApplyInPlace) {
    Document doc(fromjson("{a: [{b: 0},{b: 1},{b: 1}]}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_TRUE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: [{b: 0},{b: 1},{b: 2}]}"), doc);
}

TEST(IndexedMod, PrepareApplyNormalArray) {
    Document doc(fromjson("{a: [{b: 0},{b: 1}]}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: [{b: 0},{b: 1},{b: 2}]}"), doc);
}

TEST(IndexedMod, PrepareApplyPaddingArray) {
    Document doc(fromjson("{a: [{b: 0}]}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: [{b: 0},null,{b: 2}]}"), doc);
}

TEST(IndexedMod, PrepareApplyNumericObject) {
    Document doc(fromjson("{a: {b: 0}}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {b: 0, '2': {b: 2}}}"), doc);
}

TEST(IndexedMod, PrepareApplyNumericField) {
    Document doc(fromjson("{a: {'2': {b: 1}}}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_TRUE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {'2': {b: 2}}}"), doc);
}

TEST(IndexedMod, PrepareApplyExtendNumericField) {
    Document doc(fromjson("{a: {'2': {c: 1}}}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {'2': {c: 1, b: 2}}}"), doc);
}

TEST(IndexedMod, PrepareApplyEmptyObject) {
    Document doc(fromjson("{a: {}}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {'2': {b: 2}}}"), doc);
}

TEST(IndexedMod, PrepareApplyEmptyArray) {
    Document doc(fromjson("{a: []}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: [null, null, {b: 2}]}"), doc);
}

TEST(IndexedMod, PrepareApplyInexistent) {
    Document doc(fromjson("{}"));
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.2.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {'2': {b: 2}}}"), doc);
}

TEST(IndexedMod, LogNormal) {
    BSONObj obj = fromjson("{a: [{b:0}, {b:1}]}");
    Document doc(obj);
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    Document logDoc;
    LogBuilder logBuilder(logDoc.root());
    ASSERT_OK(setMod.log(&logBuilder));
    ASSERT_EQUALS(countChildren(logDoc.root()), 1u);
    ASSERT_EQUALS(fromjson("{$set: {'a.2.b': 2}}"), logDoc);
}

TEST(IndexedMod, LogEmptyArray) {
    BSONObj obj = fromjson("{a: []}");
    Document doc(obj);
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    Document logDoc;
    LogBuilder logBuilder(logDoc.root());
    ASSERT_OK(setMod.log(&logBuilder));
    ASSERT_EQUALS(countChildren(logDoc.root()), 1u);
    ASSERT_EQUALS(fromjson("{$set: {'a.2.b': 2}}"), logDoc);
}

TEST(IndexedMod, LogEmptyObject) {
    BSONObj obj = fromjson("{a: []}");
    Document doc(obj);
    Mod setMod(fromjson("{$set: {'a.2.b': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    Document logDoc;
    LogBuilder logBuilder(logDoc.root());
    ASSERT_OK(setMod.log(&logBuilder));
    ASSERT_EQUALS(countChildren(logDoc.root()), 1u);
    ASSERT_EQUALS(fromjson("{$set: {'a.2.b': 2}}"), logDoc);
}

//
// Indexed complex mod
//

TEST(IndexedComplexMod, PrepareNoOp) {
    Document doc(fromjson("{a: [{b: {c: 0, d: 0}}, {b: {c: 1, d: 1}}]}}"));
    Mod setMod(fromjson("{$set: {'a.1.b': {c: 1, d: 1}}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.1.b");
    ASSERT_TRUE(execInfo.noOp);
}

TEST(IndexedComplexMod, PrepareSameStructure) {
    Document doc(fromjson("{a: [{b: {c: 0, d: 0}}, {b: {c: 1, xxx: 1}}]}}"));
    Mod setMod(fromjson("{$set: {'a.1.b': {c: 1, d: 1}}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.1.b");
    ASSERT_FALSE(execInfo.noOp);
}

//
// Replication version where viable paths don't block modification
//
TEST(NonViablePathWithoutRepl, ControlRun) {
    Document doc(fromjson("{a: 1}"));
    Mod setMod(fromjson("{$set: {'a.1.b': 1}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_NOT_OK(setMod.prepare(doc.root(), "", &execInfo));
}

TEST(NonViablePathWithRepl, SingleField) {
    Document doc(fromjson("{_id:1, a: 1}"));
    Mod setMod(fromjson("{$set: {'a.1.b': 1}}"), true);

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.1.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{_id:1, a: {'1': {b: 1}}}"), doc);
}

TEST(NonViablePathWithRepl, SingleFieldNoId) {
    Document doc(fromjson("{a: 1}"));
    Mod setMod(fromjson("{$set: {'a.1.b': 1}}"), true);

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.1.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {'1': {b: 1}}}"), doc);
}

TEST(NonViablePathWithRepl, NestedField) {
    Document doc(fromjson("{_id:1, a: {a: 1}}"));
    Mod setMod(fromjson("{$set: {'a.a.1.b': 1}}"), true);

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.a.1.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{_id:1, a: {a: {'1': {b: 1}}}}"), doc);
}

TEST(NonViablePathWithRepl, DoubleNestedField) {
    Document doc(fromjson("{_id:1, a: {b: {c: 1}}}"));
    Mod setMod(fromjson("{$set: {'a.b.c.d': 2}}"), true);

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.b.c.d");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{_id:1, a: {b: {c: {d: 2}}}}"), doc);
}

TEST(NonViablePathWithRepl, NestedFieldNoId) {
    Document doc(fromjson("{a: {a: 1}}"));
    Mod setMod(fromjson("{$set: {'a.a.1.b': 1}}"), true);

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.a.1.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{a: {a: {'1': {b: 1}}}}"), doc);
}

TEST(NonViablePathWithRepl, ReplayArrayFieldNotAppendedItermediate) {
    Document doc(fromjson("{_id: 0, a: [1, {b: [1]}]}"));
    Mod setMod(fromjson("{$set: {'a.0.b': [0,2]}}}"), true);

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "a.0.b");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{_id: 0, a: [{b: [0,2]}, {b: [1]}]}"), doc);
}

// Cases from users/issues/jstests
TEST(JsTestIssues, Set6) {
    Document doc(fromjson("{_id: 1, r: {a:1, b:2}}"));
    Mod setMod(fromjson("{$set: {'r.a': 2}}"));

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "r.a");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_TRUE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{_id: 1, r: {a:2, b:2}}"), doc);

    Document logDoc;
    LogBuilder logBuilder(logDoc.root());
    ASSERT_OK(setMod.log(&logBuilder));
    ASSERT_EQUALS(countChildren(logDoc.root()), 1u);
    ASSERT_EQUALS(fromjson("{$set: {'r.a': 2}}"), logDoc);
}

// Test which failed before and is here to verify correct execution.
TEST(JsTestIssues, Set6FromRepl) {
    Document doc(fromjson("{_id: 1, r: {a:1, b:2}}"));
    Mod setMod(fromjson("{$set: { 'r.a': 2}}"), true);

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "r.a");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_TRUE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{_id: 1, r: {a:2, b:2} }"), doc);

    Document logDoc;
    LogBuilder logBuilder(logDoc.root());
    ASSERT_OK(setMod.log(&logBuilder));
    ASSERT_EQUALS(countChildren(logDoc.root()), 1u);
    ASSERT_EQUALS(fromjson("{$set: {'r.a': 2}}"), logDoc);
}

TEST(Ephemeral, ApplySetModToEphemeralDocument) {
    // The following mod when applied to a document constructed node by node exposed a
    // latent debug only defect in mutable BSON, so this is more a test of mutable than
    // $set.
    Document doc;
    Element x = doc.makeElementObject("x");
    doc.root().pushBack(x);
    Element a = doc.makeElementInt("a", 100);
    x.pushBack(a);

    Mod setMod(fromjson("{ $set: { x: { a: 100, b: 2 }}}"), true);

    ModifierInterface::ExecInfo execInfo;
    ASSERT_OK(setMod.prepare(doc.root(), "", &execInfo));

    ASSERT_EQUALS(execInfo.fieldRef[0]->dottedField(), "x");
    ASSERT_FALSE(execInfo.noOp);

    ASSERT_OK(setMod.apply());
    ASSERT_FALSE(doc.isInPlaceModeEnabled());
    ASSERT_EQUALS(fromjson("{ x : { a : 100, b : 2 } }"), doc);
}

}  // unnamed namespace