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diff --git a/src/google/protobuf/util/message_differencer.h b/src/google/protobuf/util/message_differencer.h new file mode 100644 index 00000000..654d1a67 --- /dev/null +++ b/src/google/protobuf/util/message_differencer.h @@ -0,0 +1,849 @@ +// Protocol Buffers - Google's data interchange format +// Copyright 2008 Google Inc. All rights reserved. +// https://developers.google.com/protocol-buffers/ +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +// Author: jschorr@google.com (Joseph Schorr) +// Based on original Protocol Buffers design by +// Sanjay Ghemawat, Jeff Dean, and others. +// +// This file defines static methods and classes for comparing Protocol +// Messages. +// +// Aug. 2008: Added Unknown Fields Comparison for messages. +// Aug. 2009: Added different options to compare repeated fields. +// Apr. 2010: Moved field comparison to FieldComparator. + +#ifndef GOOGLE_PROTOBUF_UTIL_MESSAGE_DIFFERENCER_H__ +#define GOOGLE_PROTOBUF_UTIL_MESSAGE_DIFFERENCER_H__ + +#include <map> +#include <set> +#include <string> +#include <vector> +#include <google/protobuf/descriptor.h> // FieldDescriptor +#include <google/protobuf/message.h> // Message +#include <google/protobuf/unknown_field_set.h> +#include <google/protobuf/util/field_comparator.h> + +namespace google { +namespace protobuf { + +class DynamicMessageFactory; +class FieldDescriptor; + +namespace io { +class ZeroCopyOutputStream; +class Printer; +} + +namespace util { + +class FieldContext; // declared below MessageDifferencer + +// A basic differencer that can be used to determine +// the differences between two specified Protocol Messages. If any differences +// are found, the Compare method will return false, and any differencer reporter +// specified via ReportDifferencesTo will have its reporting methods called (see +// below for implementation of the report). Based off of the original +// ProtocolDifferencer implementation in //net/proto/protocol-differencer.h +// (Thanks Todd!). +// +// MessageDifferencer REQUIRES that compared messages be the same type, defined +// as messages that share the same descriptor. If not, the behavior of this +// class is undefined. +// +// People disagree on what MessageDifferencer should do when asked to compare +// messages with different descriptors. Some people think it should always +// return false. Others expect it to try to look for similar fields and +// compare them anyway -- especially if the descriptors happen to be identical. +// If we chose either of these behaviors, some set of people would find it +// surprising, and could end up writing code expecting the other behavior +// without realizing their error. Therefore, we forbid that usage. +// +// This class is implemented based on the proto2 reflection. The performance +// should be good enough for normal usages. However, for places where the +// performance is extremely sensitive, there are several alternatives: +// - Comparing serialized string +// Downside: false negatives (there are messages that are the same but their +// serialized strings are different). +// - Equals code generator by compiler plugin (net/proto2/contrib/equals_plugin) +// Downside: more generated code; maintenance overhead for the additional rule +// (must be in sync with the original proto_library). +// +// Note on handling of google.protobuf.Any: MessageDifferencer automatically +// unpacks Any::value into a Message and compares its individual fields. +// Messages encoded in a repeated Any cannot be compared using TreatAsMap. +// +// +// Note on thread-safety: MessageDifferencer is *not* thread-safe. You need to +// guard it with a lock to use the same MessageDifferencer instance from +// multiple threads. Note that it's fine to call static comparison methods +// (like MessageDifferencer::Equals) concurrently. +class LIBPROTOBUF_EXPORT MessageDifferencer { + public: + // Determines whether the supplied messages are equal. Equality is defined as + // all fields within the two messages being set to the same value. Primitive + // fields and strings are compared by value while embedded messages/groups + // are compared as if via a recursive call. Use IgnoreField() and Compare() + // if some fields should be ignored in the comparison. + // + // This method REQUIRES that the two messages have the same + // Descriptor (message1.GetDescriptor() == message2.GetDescriptor()). + static bool Equals(const Message& message1, const Message& message2); + + // Determines whether the supplied messages are equivalent. Equivalency is + // defined as all fields within the two messages having the same value. This + // differs from the Equals method above in that fields with default values + // are considered set to said value automatically. For details on how default + // values are defined for each field type, see http://shortn/_x2Gv6XFrWt. + // Also, Equivalent() ignores unknown fields. Use IgnoreField() and Compare() + // if some fields should be ignored in the comparison. + // + // This method REQUIRES that the two messages have the same + // Descriptor (message1.GetDescriptor() == message2.GetDescriptor()). + static bool Equivalent(const Message& message1, const Message& message2); + + // Determines whether the supplied messages are approximately equal. + // Approximate equality is defined as all fields within the two messages + // being approximately equal. Primitive (non-float) fields and strings are + // compared by value, floats are compared using MathUtil::AlmostEquals() and + // embedded messages/groups are compared as if via a recursive call. Use + // IgnoreField() and Compare() if some fields should be ignored in the + // comparison. + // + // This method REQUIRES that the two messages have the same + // Descriptor (message1.GetDescriptor() == message2.GetDescriptor()). + static bool ApproximatelyEquals(const Message& message1, + const Message& message2); + + // Determines whether the supplied messages are approximately equivalent. + // Approximate equivalency is defined as all fields within the two messages + // being approximately equivalent. As in + // MessageDifferencer::ApproximatelyEquals, primitive (non-float) fields and + // strings are compared by value, floats are compared using + // MathUtil::AlmostEquals() and embedded messages/groups are compared as if + // via a recursive call. However, fields with default values are considered + // set to said value, as per MessageDiffencer::Equivalent. Use IgnoreField() + // and Compare() if some fields should be ignored in the comparison. + // + // This method REQUIRES that the two messages have the same + // Descriptor (message1.GetDescriptor() == message2.GetDescriptor()). + static bool ApproximatelyEquivalent(const Message& message1, + const Message& message2); + + // Identifies an individual field in a message instance. Used for field_path, + // below. + struct SpecificField { + // For known fields, "field" is filled in and "unknown_field_number" is -1. + // For unknown fields, "field" is NULL, "unknown_field_number" is the field + // number, and "unknown_field_type" is its type. + const FieldDescriptor* field; + int unknown_field_number; + UnknownField::Type unknown_field_type; + + // If this a repeated field, "index" is the index within it. For unknown + // fields, this is the index of the field among all unknown fields of the + // same field number and type. + int index; + + // If "field" is a repeated field which is being treated as a map or + // a set (see TreatAsMap() and TreatAsSet(), below), new_index indicates + // the index the position to which the element has moved. This only + // applies to ReportMoved() and (in the case of TreatAsMap()) + // ReportModified(). In all other cases, "new_index" will have the same + // value as "index". + int new_index; + + // For unknown fields, these are the pointers to the UnknownFieldSet + // containing the unknown fields. In certain cases (e.g. proto1's + // MessageSet, or nested groups of unknown fields), these may differ from + // the messages' internal UnknownFieldSets. + const UnknownFieldSet* unknown_field_set1; + const UnknownFieldSet* unknown_field_set2; + + // For unknown fields, these are the index of the field within the + // UnknownFieldSets. One or the other will be -1 when + // reporting an addition or deletion. + int unknown_field_index1; + int unknown_field_index2; + + SpecificField() + : field(NULL), + unknown_field_number(-1), + index(-1), + new_index(-1), + unknown_field_set1(NULL), + unknown_field_set2(NULL), + unknown_field_index1(-1), + unknown_field_index2(-1) {} + }; + + // Abstract base class from which all MessageDifferencer + // reporters derive. The five Report* methods below will be called when + // a field has been added, deleted, modified, moved, or matched. The third + // argument is a vector of FieldDescriptor pointers which describes the chain + // of fields that was taken to find the current field. For example, for a + // field found in an embedded message, the vector will contain two + // FieldDescriptors. The first will be the field of the embedded message + // itself and the second will be the actual field in the embedded message + // that was added/deleted/modified. + class LIBPROTOBUF_EXPORT Reporter { + public: + Reporter(); + virtual ~Reporter(); + + // Reports that a field has been added into Message2. + virtual void ReportAdded( + const Message& message1, const Message& message2, + const vector<SpecificField>& field_path) = 0; + + // Reports that a field has been deleted from Message1. + virtual void ReportDeleted( + const Message& message1, + const Message& message2, + const vector<SpecificField>& field_path) = 0; + + // Reports that the value of a field has been modified. + virtual void ReportModified( + const Message& message1, + const Message& message2, + const vector<SpecificField>& field_path) = 0; + + // Reports that a repeated field has been moved to another location. This + // only applies when using TreatAsSet or TreatAsMap() -- see below. Also + // note that for any given field, ReportModified and ReportMoved are + // mutually exclusive. If a field has been both moved and modified, then + // only ReportModified will be called. + virtual void ReportMoved( + const Message& message1, + const Message& message2, + const vector<SpecificField>& field_path) { } + + // Reports that two fields match. Useful for doing side-by-side diffs. + // This function is mutually exclusive with ReportModified and ReportMoved. + // Note that you must call set_report_matches(true) before calling Compare + // to make use of this function. + virtual void ReportMatched( + const Message& message1, + const Message& message2, + const vector<SpecificField>& field_path) { } + + // Reports that two fields would have been compared, but the + // comparison has been skipped because the field was marked as + // 'ignored' using IgnoreField(). This function is mutually + // exclusive with all the other Report() functions. + // + // The contract of ReportIgnored is slightly different than the + // other Report() functions, in that |field_path.back().index| is + // always equal to -1, even if the last field is repeated. This is + // because while the other Report() functions indicate where in a + // repeated field the action (Addition, Deletion, etc...) + // happened, when a repeated field is 'ignored', the differencer + // simply calls ReportIgnored on the repeated field as a whole and + // moves on without looking at its individual elements. + // + // Furthermore, ReportIgnored() does not indicate whether the + // fields were in fact equal or not, as Compare() does not inspect + // these fields at all. It is up to the Reporter to decide whether + // the fields are equal or not (perhaps with a second call to + // Compare()), if it cares. + virtual void ReportIgnored( + const Message& message1, + const Message& message2, + const vector<SpecificField>& field_path) { } + + // Report that an unknown field is ignored. (see comment above). + // Note this is a different function since the last SpecificField in field + // path has a null field. This could break existing Reporter. + virtual void ReportUnknownFieldIgnored( + const Message& message1, const Message& message2, + const vector<SpecificField>& field_path) {} + + private: + GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(Reporter); + }; + + // MapKeyComparator is used to determine if two elements have the same key + // when comparing elements of a repeated field as a map. + class LIBPROTOBUF_EXPORT MapKeyComparator { + public: + MapKeyComparator(); + virtual ~MapKeyComparator(); + + virtual bool IsMatch(const Message& message1, + const Message& message2, + const vector<SpecificField>& parent_fields) const { + GOOGLE_CHECK(false) << "IsMatch() is not implemented."; + return false; + } + + private: + GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MapKeyComparator); + }; + + // Abstract base class from which all IgnoreCriteria derive. + // By adding IgnoreCriteria more complex ignore logic can be implemented. + // IgnoreCriteria are registed with AddIgnoreCriteria. For each compared + // field IsIgnored is called on each added IgnoreCriteria until one returns + // true or all return false. + // IsIgnored is called for fields where at least one side has a value. + class LIBPROTOBUF_EXPORT IgnoreCriteria { + public: + IgnoreCriteria(); + virtual ~IgnoreCriteria(); + + // Returns true if the field should be ignored. + virtual bool IsIgnored( + const Message& message1, + const Message& message2, + const FieldDescriptor* field, + const vector<SpecificField>& parent_fields) = 0; + + // Returns true if the unknown field should be ignored. + // Note: This will be called for unknown fields as well in which case + // field.field will be null. + virtual bool IsUnknownFieldIgnored( + const Message& message1, const Message& message2, + const SpecificField& field, + const vector<SpecificField>& parent_fields) { + return false; + } + }; + + // To add a Reporter, construct default here, then use ReportDifferencesTo or + // ReportDifferencesToString. + explicit MessageDifferencer(); + + ~MessageDifferencer(); + + enum MessageFieldComparison { + EQUAL, // Fields must be present in both messages + // for the messages to be considered the same. + EQUIVALENT, // Fields with default values are considered set + // for comparison purposes even if not explicitly + // set in the messages themselves. Unknown fields + // are ignored. + }; + + enum Scope { + FULL, // All fields of both messages are considered in the comparison. + PARTIAL // Only fields present in the first message are considered; fields + // set only in the second message will be skipped during + // comparison. + }; + + // DEPRECATED. Use FieldComparator::FloatComparison instead. + enum FloatComparison { + EXACT, // Floats and doubles are compared exactly. + APPROXIMATE // Floats and doubles are compared using the + // MathUtil::AlmostEquals method. + }; + + enum RepeatedFieldComparison { + AS_LIST, // Repeated fields are compared in order. Differing values at + // the same index are reported using ReportModified(). If the + // repeated fields have different numbers of elements, the + // unpaired elements are reported using ReportAdded() or + // ReportDeleted(). + AS_SET, // Treat all the repeated fields as sets by default. + // See TreatAsSet(), as below. + }; + + // The elements of the given repeated field will be treated as a set for + // diffing purposes, so different orderings of the same elements will be + // considered equal. Elements which are present on both sides of the + // comparison but which have changed position will be reported with + // ReportMoved(). Elements which only exist on one side or the other are + // reported with ReportAdded() and ReportDeleted() regardless of their + // positions. ReportModified() is never used for this repeated field. If + // the only differences between the compared messages is that some fields + // have been moved, then the comparison returns true. + // + // If the scope of comparison is set to PARTIAL, then in addition to what's + // above, extra values added to repeated fields of the second message will + // not cause the comparison to fail. + // + // Note that set comparison is currently O(k * n^2) (where n is the total + // number of elements, and k is the average size of each element). In theory + // it could be made O(n * k) with a more complex hashing implementation. Feel + // free to contribute one if the current implementation is too slow for you. + // If partial matching is also enabled, the time complexity will be O(k * n^2 + // + n^3) in which n^3 is the time complexity of the maximum matching + // algorithm. + // + // REQUIRES: field->is_repeated() and field not registered with TreatAsList + void TreatAsSet(const FieldDescriptor* field); + + // The elements of the given repeated field will be treated as a list for + // diffing purposes, so different orderings of the same elements will NOT be + // considered equal. + // + // REQUIRED: field->is_repeated() and field not registered with TreatAsSet + void TreatAsList(const FieldDescriptor* field); + + // The elements of the given repeated field will be treated as a map for + // diffing purposes, with |key| being the map key. Thus, elements with the + // same key will be compared even if they do not appear at the same index. + // Differences are reported similarly to TreatAsSet(), except that + // ReportModified() is used to report elements with the same key but + // different values. Note that if an element is both moved and modified, + // only ReportModified() will be called. As with TreatAsSet, if the only + // differences between the compared messages is that some fields have been + // moved, then the comparison returns true. See TreatAsSet for notes on + // performance. + // + // REQUIRES: field->is_repeated() + // REQUIRES: field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE + // REQUIRES: key->containing_type() == field->message_type() + void TreatAsMap(const FieldDescriptor* field, const FieldDescriptor* key); + // Same as TreatAsMap except that this method will use multiple fields as + // the key in comparison. All specified fields in 'key_fields' should be + // present in the compared elements. Two elements will be treated as having + // the same key iff they have the same value for every specified field. There + // are two steps in the comparison process. The first one is key matching. + // Every element from one message will be compared to every element from + // the other message. Only fields in 'key_fields' are compared in this step + // to decide if two elements have the same key. The second step is value + // comparison. Those pairs of elements with the same key (with equal value + // for every field in 'key_fields') will be compared in this step. + // Time complexity of the first step is O(s * m * n ^ 2) where s is the + // average size of the fields specified in 'key_fields', m is the number of + // fields in 'key_fields' and n is the number of elements. If partial + // matching is enabled, an extra O(n^3) will be incured by the maximum + // matching algorithm. The second step is O(k * n) where k is the average + // size of each element. + void TreatAsMapWithMultipleFieldsAsKey( + const FieldDescriptor* field, + const vector<const FieldDescriptor*>& key_fields); + // Same as TreatAsMapWithMultipleFieldsAsKey, except that each of the field + // do not necessarily need to be a direct subfield. Each element in + // key_field_paths indicate a path from the message being compared, listing + // successive subfield to reach the key field. + // + // REQUIRES: + // for key_field_path in key_field_paths: + // key_field_path[0]->containing_type() == field->message_type() + // for i in [0, key_field_path.size() - 1): + // key_field_path[i+1]->containing_type() == + // key_field_path[i]->message_type() + // key_field_path[i]->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE + // !key_field_path[i]->is_repeated() + void TreatAsMapWithMultipleFieldPathsAsKey( + const FieldDescriptor* field, + const vector<vector<const FieldDescriptor*> >& key_field_paths); + + // Uses a custom MapKeyComparator to determine if two elements have the same + // key when comparing a repeated field as a map. + // The caller is responsible to delete the key_comparator. + // This method varies from TreatAsMapWithMultipleFieldsAsKey only in the + // first key matching step. Rather than comparing some specified fields, it + // will invoke the IsMatch method of the given 'key_comparator' to decide if + // two elements have the same key. + void TreatAsMapUsingKeyComparator( + const FieldDescriptor* field, + const MapKeyComparator* key_comparator); + + // Add a custom ignore criteria that is evaluated in addition to the + // ignored fields added with IgnoreField. + // Takes ownership of ignore_criteria. + void AddIgnoreCriteria(IgnoreCriteria* ignore_criteria); + + // Indicates that any field with the given descriptor should be + // ignored for the purposes of comparing two messages. This applies + // to fields nested in the message structure as well as top level + // ones. When the MessageDifferencer encounters an ignored field, + // ReportIgnored is called on the reporter, if one is specified. + // + // The only place where the field's 'ignored' status is not applied is when + // it is being used as a key in a field passed to TreatAsMap or is one of + // the fields passed to TreatAsMapWithMultipleFieldsAsKey. + // In this case it is compared in key matching but after that it's ignored + // in value comparison. + void IgnoreField(const FieldDescriptor* field); + + // Sets the field comparator used to determine differences between protocol + // buffer fields. By default it's set to a DefaultFieldComparator instance. + // MessageDifferencer doesn't take ownership over the passed object. + // Note that this method must be called before Compare for the comparator to + // be used. + void set_field_comparator(FieldComparator* comparator); + + // DEPRECATED. Pass a DefaultFieldComparator instance instead. + // Sets the fraction and margin for the float comparison of a given field. + // Uses MathUtil::WithinFractionOrMargin to compare the values. + // NOTE: this method does nothing if differencer's field comparator has been + // set to a custom object. + // + // REQUIRES: field->cpp_type == FieldDescriptor::CPPTYPE_DOUBLE or + // field->cpp_type == FieldDescriptor::CPPTYPE_FLOAT + // REQUIRES: float_comparison_ == APPROXIMATE + void SetFractionAndMargin(const FieldDescriptor* field, double fraction, + double margin); + + // Sets the type of comparison (as defined in the MessageFieldComparison + // enumeration above) that is used by this differencer when determining how + // to compare fields in messages. + void set_message_field_comparison(MessageFieldComparison comparison); + + // Tells the differencer whether or not to report matches. This method must + // be called before Compare. The default for a new differencer is false. + void set_report_matches(bool report_matches) { + report_matches_ = report_matches; + } + + // Sets the scope of the comparison (as defined in the Scope enumeration + // above) that is used by this differencer when determining which fields to + // compare between the messages. + void set_scope(Scope scope); + + // Returns the current scope used by this differencer. + Scope scope(); + + // DEPRECATED. Pass a DefaultFieldComparator instance instead. + // Sets the type of comparison (as defined in the FloatComparison enumeration + // above) that is used by this differencer when comparing float (and double) + // fields in messages. + // NOTE: this method does nothing if differencer's field comparator has been + // set to a custom object. + void set_float_comparison(FloatComparison comparison); + + // Sets the type of comparison for repeated field (as defined in the + // RepeatedFieldComparison enumeration above) that is used by this + // differencer when compare repeated fields in messages. + void set_repeated_field_comparison(RepeatedFieldComparison comparison); + + // Compares the two specified messages, returning true if they are the same, + // false otherwise. If this method returns false, any changes between the + // two messages will be reported if a Reporter was specified via + // ReportDifferencesTo (see also ReportDifferencesToString). + // + // This method REQUIRES that the two messages have the same + // Descriptor (message1.GetDescriptor() == message2.GetDescriptor()). + bool Compare(const Message& message1, const Message& message2); + + // Same as above, except comparing only the list of fields specified by the + // two vectors of FieldDescriptors. + bool CompareWithFields(const Message& message1, const Message& message2, + const vector<const FieldDescriptor*>& message1_fields, + const vector<const FieldDescriptor*>& message2_fields); + + // Automatically creates a reporter that will output the differences + // found (if any) to the specified output string pointer. Note that this + // method must be called before Compare. + void ReportDifferencesToString(string* output); + + // Tells the MessageDifferencer to report differences via the specified + // reporter. Note that this method must be called before Compare for + // the reporter to be used. It is the responsibility of the caller to delete + // this object. + // If the provided pointer equals NULL, the MessageDifferencer stops reporting + // differences to any previously set reporters or output strings. + void ReportDifferencesTo(Reporter* reporter); + + // An implementation of the MessageDifferencer Reporter that outputs + // any differences found in human-readable form to the supplied + // ZeroCopyOutputStream or Printer. If a printer is used, the delimiter + // *must* be '$'. + // + // WARNING: this reporter does not necessarily flush its output until it is + // destroyed. As a result, it is not safe to assume the output is valid or + // complete until after you destroy the reporter. For example, if you use a + // StreamReporter to write to a StringOutputStream, the target string may + // contain uninitialized data until the reporter is destroyed. + class LIBPROTOBUF_EXPORT StreamReporter : public Reporter { + public: + explicit StreamReporter(io::ZeroCopyOutputStream* output); + explicit StreamReporter(io::Printer* printer); // delimiter '$' + virtual ~StreamReporter(); + + // When set to true, the stream reporter will also output aggregates nodes + // (i.e. messages and groups) whose subfields have been modified. When + // false, will only report the individual subfields. Defaults to false. + void set_report_modified_aggregates(bool report) { + report_modified_aggregates_ = report; + } + + // The following are implementations of the methods described above. + virtual void ReportAdded(const Message& message1, const Message& message2, + const vector<SpecificField>& field_path); + + virtual void ReportDeleted(const Message& message1, + const Message& message2, + const vector<SpecificField>& field_path); + + virtual void ReportModified(const Message& message1, + const Message& message2, + const vector<SpecificField>& field_path); + + virtual void ReportMoved(const Message& message1, + const Message& message2, + const vector<SpecificField>& field_path); + + virtual void ReportMatched(const Message& message1, + const Message& message2, + const vector<SpecificField>& field_path); + + virtual void ReportIgnored(const Message& message1, + const Message& message2, + const vector<SpecificField>& field_path); + + virtual void ReportUnknownFieldIgnored( + const Message& message1, const Message& message2, + const vector<SpecificField>& field_path); + + protected: + // Prints the specified path of fields to the buffer. + virtual void PrintPath(const vector<SpecificField>& field_path, + bool left_side); + + // Prints the value of fields to the buffer. left_side is true if the + // given message is from the left side of the comparison, false if it + // was the right. This is relevant only to decide whether to follow + // unknown_field_index1 or unknown_field_index2 when an unknown field + // is encountered in field_path. + virtual void PrintValue(const Message& message, + const vector<SpecificField>& field_path, + bool left_side); + + // Prints the specified path of unknown fields to the buffer. + virtual void PrintUnknownFieldValue(const UnknownField* unknown_field); + + // Just print a string + void Print(const string& str); + + private: + io::Printer* printer_; + bool delete_printer_; + bool report_modified_aggregates_; + + GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(StreamReporter); + }; + + private: + // A MapKeyComparator to be used in TreatAsMapUsingKeyComparator. + // Implementation of this class needs to do field value comparison which + // relies on some private methods of MessageDifferencer. That's why this + // class is declared as a nested class of MessageDifferencer. + class MultipleFieldsMapKeyComparator; + // Returns true if field1's number() is less than field2's. + static bool FieldBefore(const FieldDescriptor* field1, + const FieldDescriptor* field2); + + // Combine the two lists of fields into the combined_fields output vector. + // All fields present in both lists will always be included in the combined + // list. Fields only present in one of the lists will only appear in the + // combined list if the corresponding fields_scope option is set to FULL. + void CombineFields(const vector<const FieldDescriptor*>& fields1, + Scope fields1_scope, + const vector<const FieldDescriptor*>& fields2, + Scope fields2_scope, + vector<const FieldDescriptor*>* combined_fields); + + // Internal version of the Compare method which performs the actual + // comparison. The parent_fields vector is a vector containing field + // descriptors of all fields accessed to get to this comparison operation + // (i.e. if the current message is an embedded message, the parent_fields + // vector will contain the field that has this embedded message). + bool Compare(const Message& message1, const Message& message2, + vector<SpecificField>* parent_fields); + + // Compares all the unknown fields in two messages. + bool CompareUnknownFields(const Message& message1, const Message& message2, + const google::protobuf::UnknownFieldSet&, + const google::protobuf::UnknownFieldSet&, + vector<SpecificField>* parent_fields); + + // Compares the specified messages for the requested field lists. The field + // lists are modified depending on comparison settings, and then passed to + // CompareWithFieldsInternal. + bool CompareRequestedFieldsUsingSettings( + const Message& message1, const Message& message2, + const vector<const FieldDescriptor*>& message1_fields, + const vector<const FieldDescriptor*>& message2_fields, + vector<SpecificField>* parent_fields); + + // Compares the specified messages with the specified field lists. + bool CompareWithFieldsInternal( + const Message& message1, const Message& message2, + const vector<const FieldDescriptor*>& message1_fields, + const vector<const FieldDescriptor*>& message2_fields, + vector<SpecificField>* parent_fields); + + // Compares the repeated fields, and report the error. + bool CompareRepeatedField(const Message& message1, const Message& message2, + const FieldDescriptor* field, + vector<SpecificField>* parent_fields); + + // Shorthand for CompareFieldValueUsingParentFields with NULL parent_fields. + bool CompareFieldValue(const Message& message1, + const Message& message2, + const FieldDescriptor* field, + int index1, + int index2); + + // Compares the specified field on the two messages, returning + // true if they are the same, false otherwise. For repeated fields, + // this method only compares the value in the specified index. This method + // uses Compare functions to recurse into submessages. + // The parent_fields vector is used in calls to a Reporter instance calls. + // It can be NULL, in which case the MessageDifferencer will create new + // list of parent messages if it needs to recursively compare the given field. + // To avoid confusing users you should not set it to NULL unless you modified + // Reporter to handle the change of parent_fields correctly. + bool CompareFieldValueUsingParentFields(const Message& message1, + const Message& message2, + const FieldDescriptor* field, + int index1, + int index2, + vector<SpecificField>* parent_fields); + + // Compares the specified field on the two messages, returning comparison + // result, as returned by appropriate FieldComparator. + FieldComparator::ComparisonResult GetFieldComparisonResult( + const Message& message1, const Message& message2, + const FieldDescriptor* field, int index1, int index2, + const FieldContext* field_context); + + // Check if the two elements in the repeated field are match to each other. + // if the key_comprator is NULL, this function returns true when the two + // elements are equal. + bool IsMatch(const FieldDescriptor* repeated_field, + const MapKeyComparator* key_comparator, + const Message* message1, const Message* message2, + const vector<SpecificField>& parent_fields, + int index1, int index2); + + // Returns true when this repeated field has been configured to be treated + // as a set. + bool IsTreatedAsSet(const FieldDescriptor* field); + + // Returns true when this repeated field is to be compared as a subset, ie. + // has been configured to be treated as a set or map and scope is set to + // PARTIAL. + bool IsTreatedAsSubset(const FieldDescriptor* field); + + // Returns true if this field is to be ignored when this + // MessageDifferencer compares messages. + bool IsIgnored( + const Message& message1, + const Message& message2, + const FieldDescriptor* field, + const vector<SpecificField>& parent_fields); + + // Returns true if this unknown field is to be ignored when this + // MessageDifferencer compares messages. + bool IsUnknownFieldIgnored(const Message& message1, const Message& message2, + const SpecificField& field, + const vector<SpecificField>& parent_fields); + + // Returns MapKeyComparator* when this field has been configured to + // be treated as a map. If not, returns NULL. + const MapKeyComparator* GetMapKeyComparator(const FieldDescriptor* field); + + // Attempts to match indices of a repeated field, so that the contained values + // match. Clears output vectors and sets their values to indices of paired + // messages, ie. if message1[0] matches message2[1], then match_list1[0] == 1 + // and match_list2[1] == 0. The unmatched indices are indicated by -1. + // This method returns false if the match failed. However, it doesn't mean + // that the comparison succeeds when this method returns true (you need to + // double-check in this case). + bool MatchRepeatedFieldIndices(const Message& message1, + const Message& message2, + const FieldDescriptor* repeated_field, + const vector<SpecificField>& parent_fields, + vector<int>* match_list1, + vector<int>* match_list2); + + // If "any" is of type google.protobuf.Any, extract its payload using + // DynamicMessageFactory and store in "data". + bool UnpackAny(const Message& any, google::protobuf::scoped_ptr<Message>* data); + + // Checks if index is equal to new_index in all the specific fields. + static bool CheckPathChanged(const vector<SpecificField>& parent_fields); + + // Defines a map between field descriptors and their MapKeyComparators. + // Used for repeated fields when they are configured as TreatAsMap. + typedef map<const FieldDescriptor*, + const MapKeyComparator*> FieldKeyComparatorMap; + + // Defines a set to store field descriptors. Used for repeated fields when + // they are configured as TreatAsSet. + typedef set<const FieldDescriptor*> FieldSet; + + Reporter* reporter_; + DefaultFieldComparator default_field_comparator_; + FieldComparator* field_comparator_; + MessageFieldComparison message_field_comparison_; + Scope scope_; + RepeatedFieldComparison repeated_field_comparison_; + + FieldSet set_fields_; + FieldSet list_fields_; + // Keeps track of MapKeyComparators that are created within + // MessageDifferencer. These MapKeyComparators should be deleted + // before MessageDifferencer is destroyed. + // When TreatAsMap or TreatAsMapWithMultipleFieldsAsKey is called, we don't + // store the supplied FieldDescriptors directly. Instead, a new + // MapKeyComparator is created for comparison purpose. + vector<MapKeyComparator*> owned_key_comparators_; + FieldKeyComparatorMap map_field_key_comparator_; + vector<IgnoreCriteria*> ignore_criteria_; + + FieldSet ignored_fields_; + + bool compare_unknown_fields_; + bool report_matches_; + + string* output_string_; + + google::protobuf::scoped_ptr<DynamicMessageFactory> dynamic_message_factory_; + GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MessageDifferencer); +}; + +// This class provides extra information to the FieldComparator::Compare +// function. +class LIBPROTOBUF_EXPORT FieldContext { + public: + explicit FieldContext( + vector<MessageDifferencer::SpecificField>* parent_fields) + : parent_fields_(parent_fields) {} + + vector<MessageDifferencer::SpecificField>* parent_fields() const { + return parent_fields_; + } + + private: + vector<MessageDifferencer::SpecificField>* parent_fields_; +}; + +} +} + +} // namespace google +#endif // GOOGLE_PROTOBUF_UTIL_MESSAGE_DIFFERENCER_H__ |