8. Comparing Folders

The Folder compare window displays all of the files and subfolders compared in a sortable list view. Files and subfolders may be synchronized by copying or deleting, and actions may be performed on multiple items simultaneously. The columns displayed may be changed and reordered.

Folder comparison has two different modes. The mode is selected in the Open dialog with the "Include Subfolders"-checkbox.

In WinMerge version 2.4 and later there is a Compare by Quick Contents -compare method which makes possible to compare big binary files. For more information about different compare methods see Options & configuration -chapter. In WinMerge version 2.4 and later all files bigger than 4 MB (megabytes) are automatically compared with Compare by Quick Contents -method. Downsides for this method are that linefilters do not work and there is no difference counts information in folder compare UI. For most cases this should not matter since so big files usually are binary files.

For advanced users: If that limit does not feel good (you have lots of big text files) it can be changed via registry value:

HKEY_CURRENT_USER\Software\Thingamahoochie\WinMerge\Settings\QuickMethodLimit

. As usual be careful when changing values directly to registry!

8.1. Compare Results

Files and folders are compared and divided into several categories. Categories are easy to recognize from these icons:

Identical text files
Differing text files
Identical binary files
Differing binary files
Left-only folders
Right-only folders
Left-only files
Right-only files
Skipped directories (filtered out)
Skipped files (filtered out)
Items that couldn't be compared. This usually happens when other program has locked the file.
Aborted item. WinMerge did not finish comparing this item when compare was stopped. Result is unknown.

8.2. Folder Compare Status

During the folder comparison WinMerge shows status panel:

The panel shows approximate status and progress of the compare. Status is shown as a number of items and a progressbar. Numbers show how many items (files and folders) WinMerge has found to compare. Progressbar shows same info graphically.

[Important] Important

Progressbar is for item counts. As there usually are different sized files in compare it does not directly map to time used/remaining. So 50/100 items does not strictly mean compare is in half by time used.

Folder compare can be stopped by selecting Stop-button and results for files and folders compared so far are shown. When compare is stopped before it finishes, some files may be in middle of comparison. Those files are marked as Aborted in comparison results. It means result is not available for them.

When folder compare is ready status panel is closed and results are shown.

[Note] Note

This is one of most visible changes in WinMerge version 2.6. New status panel may feel "just too simple" after using previous WinMerge versions. The fact is most of the details in previous versions were useless during the compare. So simplicity was choosen for new design. Automatic closing may also feel weird at starters. But there is no information visible that would be needed after the compare.

Compare statistics are visible in separate dialog which can be opened after compare from menu: View->Compare Statistics.

8.3. Selecting Items to Show

In "View" menu there are several choices for selecting which categories to show / hide.

  • Show identical files : shows and hides files detected as identical
  • Show different files : shows and hides files detected as different
  • Show left unique files : shows and hides files and directories present only in left side
  • Show right unique files : shows and hides files and directories present only in right side
  • Show binary files : shows and hides files detected as binaries
  • Show skipped files : shows and hides files and directories filtered out by file filters

8.4. Columns in Folder Compare

By default these columns are visible:

  • Filename
  • Directory : Relative folder name for compare path. If subfolders are not included this is empty.
  • Comparison result : Verbose comparison result (see also Short Result)
  • Left Date & Right Date: Modification date of item. Note that newer date is prefixed with asterisk "*".
  • Extension : File's extension, handy for sorting

Following columns are available through "Customize Columns"-dialog:

  • Binary : Column contains asterisk "*" when file is binary. Handy for sorting and to use with "Short Result"-column.
  • Left Attributes & Right Attributes : Shows file attributes.
  • Left Creation Time & Right Creation Time : Item creation time.
  • Left Encoding & Right Encoding : File encoding.
  • Left File Version & Right File Version : Version number from file if present. Note that this is read for only some binary files.
  • Left Size & Right Size : File size in bytes.
  • Newer File : Shows which side is newer.
  • Differences : Amount of differences found between files, not including possibly ignored differences.
  • Ignored diff. : Amount of ignored differences in files.
  • Left EOL & Righ EOL : Show EOL style (linefeed style) of files.

8.5. Browsing Folders

Browsing folders is only possible when subfolders are not included to compare (Include Subfolders checkbox is not checked in Open-dialog). Parent folders (".."-item) and subfolders existing in both sides can be compared by double-clicking with mouse over them or selecting them and pressing Enter.

Parent folder can be opened if it is not same directory. These two icons indicate if parent folder can be opened:

Parent folder can be opened.
Parent folder cannot be opened. It probably is same directory for both sides.

8.6. Navigation in Folder Compare

In addition moving selection using mouse or keyboard, also Merge-menu navigation commands, toolbar buttons and shortcut keys can be used. For example "Next diff" finds next different file and selects it.

[Note] Note

Unique files and folders are considered as different ones.

Multiple files/folders can be selected. However not all operations are possible with multi-selection.

8.7. File Operations in Folder Compare

8.7.1. Copying, moving and deleting

Folder compare allows user to copy and delete files and folders. File operations are available through context menu (right-click with mouse). Also files can be opened to associated program or into external editor.

In file operation menu, there are one or two numbers shown, depending on files/folders selected. If there is one number shown, for example "Copy/Left to... (5)" that means there is 5 items selected, and all items can be copied. But if there is two numbers shown, for example "Copy/Left to... (3 of 5)", that means there are 5 items selected but only 3 items can be copied.

Most common operation is copying files from side to side. File can be copied from side to side using Merge-menu items, toolbar buttons and context menu. If multiple files are selected, or file to overwrite is read-only, confirmation dialog is shown.

Sometimes it is useful to copy certain files and/or directories to another directory instead of another compared directory. This can be done selecting "Copy/Left to..." or "Copy/Right to..." items.

Another file/folder operation is deleting. Items in another or both sides can be deleted. There is "Send deleted files into Recycle Bin" option in system options (See Options & Configuration -chapter). It is highly recommended to keep that option enabled so deletion can be undone if accidents happen. Note however recycle bin does not help if its disabled from Windows settings.

Moving is just shortcut for copy + delete.

[Warning] Warning

File/folder deletion cannot be undone if Recycle Bin is not used!

8.7.2. Renaming

Renaming files and folders is available through context menu item Rename or using F2 -shortcut key. Edit-box appears and allows editing of the name. Renaming can be cancelled by pressing Esc -key. Note that items in both sides are renamed. Renaming just other side is not currently possible.

8.7.3. Opening files

There are three items in Open-menus:

  • With Registered Application : Opens file with application registered for editing filetype for Windows, if there is one.
  • With External Editor : Open with external editor. Default editor can be selected from options, Notepad is used by default.
  • With ... : Opens "Open With..." dialog asking from user with which application files should be opened.
[Tip] Tip

Selecting With Registered Application when folder is selected usually opens that folder into new Explorer window.

8.7.4. Archiving

Zip-menu in directory compare context menu allows adding selected items to archive file.

[Note] Note

Archive support requires that 7-Zip plugin is installed to system.

Zip-submenumenu has four items:

  • Left... : Adds left-side files and folders (recursively) to the archive file
  • Right... : Adds right-side files and folders (recursively) to the archive file
  • Both... : Adds files and folders (recursively) from both sides to the archive file. Because filenames are same, files must be put to subfolders inside archive. Left-side files are put to subfolder Original/ and right-side files are put to subfolder Altered/.
  • Differences... : This is like above Both, but this item adds only different files (including unique files) from both sides.

After selecting one of Zip-menu items dialog pops up asking filename and archive type from user. WinMerge cannot add files to existing archive files but it always creates new archive file.

[Tip] Tip

WinMerge looks for subfolders Original/ and Altered/ in archive files. If archive file contains these subfolders and same filename is given to both sides WinMerge compares contents of those two folders.

If directory compare shows contents of archive files WinMerge updates changes done to files in file compare into original archive file. But WinMerge does not update archive contents for files added/deleted/copied. User can create a new archive file using above menuitems instead.

8.8. Copying Path- or Filenames

In context menu there are items for copying selected items' paths or filenames to clipboard. This feature makes it easy so get list of changed files, for changelogs etc.

  • Copy Pathnames has three subchoices like other file handling functions. It copies full pathnames of selected items to clipboard, one per line.
  • Copy Filenames copies only filenames without paths.

8.9. Customising Folder Compare

There are many ways to customize folder compare:

  • Sorting by column : Sorted by column can be selected by clicking column name with mouse. Little arrow appears next to column name indicating that results are sorted by this column and sort order.
  • Selecting visible columns : "Display Columns" dialog can be opened from Tools-menu or by right-clicking column header with mouse.
  • Changing order of columns : Order can be changed in "Display Columns" dialog or by drag & dropping column names with mouse.

8.10. Protecting Folders / Read-only Folders

If user wants to protect one or both sides from changes, user can set them to read-only from File-menu.

[Important] Important

Setting read-only protects files and folders in current compare view only.

Protected status is inherited to opened files from directory compare. If user compares two folders, sets another to protected and opens two files for comparing, file opened from protected side has protection set too.

Protection status is shown in statusbar, there are own panes for left and right side.

8.11. Hiding Items

Selected items can be hidden from view using context menu item Hide Items. Hidden items are not shown until next refresh is done. All hidden items can be re-shown selecting View->Show Hidden Items.

Hiding items is handy to remove already handled items from the view. So when you have merged files, use context menu item to hide them. It is a lot easier to see what items are left to merge. Get used to it! It saves your time!

8.12. Refreshing Only Selected Items

Full refresh of large folders can take a long time. In 2.2 and earlier versions of WinMerge user always had to do full refresh after editing files outside WinMerge. WinMerge 2.4 and later can refresh just selected items. Select Refresh from the context menu.