File indexing completed on 2024-05-12 05:52:07

 /*
     SPDX-FileCopyrightText: 2007 Andreas Pakulat <apaku@gmx.de>
     SPDX-FileCopyrightText: 2007 Matthew Woehlke <mw_triad@users.sourceforge.net>
     SPDX-FileCopyrightText: 2020 Jonathan Verner <jonathan.verner@matfyz.cz>
 
     SPDX-License-Identifier: LGPL-2.0-or-later
 */
 #pragma once
 
 #include <QList>
 #include <memory>
 
 class QUrl;
 class QString;
 
 /**
  * A class representing a unified diff, possibly with
  * conflict markers.
  *
  * A diff is assumed to be a collection of hunks, where each hunk has the
  * following structure:
  *
  *   METADATA
  *   --- a/SOURCE_PATH
  *   +++ b/TARGET_PATH
  *   HUNK1 HEADER
  *   HUNK1 CONTENT
  *   [METADATA]
  *   HUNK2 HEADER
  *   HUNK2 CONTENT
  *   ...
  *
  * METADATA are lines which start with anything except for a '+', '-' and ' '.
  * The path specifications may optionally precede a hunk and are assumed to
  * apply to all following hunks until a new path specification
  * is found. These indicate the files for which the diff is generated.
  *
  * Hunk Header
  * ------------
  *
  * Each hunk header has the following form
  *
  *   @@ -SRC_OFFSET[, SRC_CHANGES_COUNT] +TGT_OFFSET[, TGT_CHANGES_COUNT] @@ Heading
  *
  * where the SRC_OFFSET is a 1-based line index pointing to the source file where
  * the hunk applies and TGT_OFFSET is a 1-based line index pointing to the target
  * file where the hunk applies. The optional SRC_CHANGES_COUNTS (assumed to be 1
  * if not present) specifies the number of context lines plus the number of
  * deleted lines. Similarly, the optional TGT_CHANGES_COUNT specifies the
  * number of context lines plus the number of added lines. The Heading, used as a
  * visual aid for users, is supposed to show the line where the nearest enclosing
  * function scope of the hunk starts.
  *
  * Hunk Content
  * ------------
  *
  * The hunk content is a collection of lines which starting with '+' (additions),
  * '-' (deletions) and ' ' (context lines; empty lines are also take to be context
  * lines). Additionally, a hunk may contain conflict markers which are of the form
  *
  *   >>>>>>> our ref
  *   our content
  *   ...
  *   =======
  *   their content
  *   ...
  *   <<<<<<< their ref
  *
  * and indicate unresolved conflicts.
  *
  */
 class VcsDiff
 {
 public:
     /* Used to represent a patch or its inverse */
     enum DiffDirection {
         Normal = 0 /**< the unchanged patch */
         ,
         Forward = 0 /**< the unchanged patch */
         ,
         Reverse = 1 /**< the inverse of the patch (i.e. a new patch which, when applied, undoes the old patch) */
     };
 
     VcsDiff();
     ~VcsDiff();
     VcsDiff(VcsDiff &&rhs);
 
     /**
      * @returns the source of the diff.
      */
     QString diff() const;
 
     /** @returns the base directory of the diff. */
     QUrl baseDiff() const;
 
     /**
      * Depth - number of directories to left-strip from paths in the patch - see "patch -p"
      * Defaults to 0
      */
     uint depth() const;
 
     /** Sets the base directory of the diff to the @p url */
     void setBaseDiff(const QUrl &url);
 
     /** Sets the depth of the diff to @p depth */
     void setDepth(const uint depth);
 
     /** Sets the diff source and parses it.
      *
      * @param diff the diff in unified diff format
      */
     void setDiff(const QString &diff);
 
     /** @returns whether or not there are changes in the diff */
     bool isEmpty() const;
 
     /**
      * Creates a standalone diff containing the differences in a given range.
      *
      * @returns a diff containing only the changes from the current diff
      *  which are in the range startLine-endLine (in the diff text)
      *
      * @param startLine 0-based line number (in the diff) of the first line in the range
      * @param endLine 0-based line number (in the diff) of the last line in the range
      * @param dir if set to Reverse, the role of src and tgt are reversed, i.e. a diff is
      *            generated which can be applied to the target to get the source.
      */
     VcsDiff subDiff(const uint startLine, const uint endLine, DiffDirection dir = Normal) const;
 
     /**
      * Creates a new standalone diff from a single hunk identified by a containing line.
      *
      * @returns a diff containing only the changes from hunk containing
      * the line the line
      *
      * @param line 0-based line number (in the diff) of the line in the hunk
      * @param dir if set to Reverse, the role of src and tgt are reversed, i.e. a diff is
      *            generated which can be applied to the target to get the source.
      */
     VcsDiff subDiffHunk(const uint line, DiffDirection dir = Normal) const;
 
     /**
      * Maps a line position in the diff to a corresponding line position in the source file.
      *
      * @param line a 0-based line position in the diff
      * @returns the 0-based line position in the source file or -1 if no such position exists.
      */
     int diffLineToSourceLine(const uint line) const;
 
     /**
      * Maps a line position in the diff to a corresponding line position in the source file.
      *
      * @param line a 0-based line position in the diff
      * @returns the 0-based line position in the source file or -1 if no such position exists.
      */
     int diffLineToTargetLine(const uint line) const;
 
 private:
     std::unique_ptr<class VcsDiffPrivate> d;
 };
 
 // Helper, parses "123, 12" into ints
 std::pair<uint, uint> parseRange(const QString &range);