| 69 |   | A very frequent need is to look at changes made on a file  | 
          
          
            | 70 |   | or on a directory spanning multiple revisions.  | 
          
          
            | 71 |   | The easiest way to get there is from the TracRevisionLog,  | 
          
          
            | 72 |   | where one can select the '''old''' and the '''new''' revisions | 
          
          
            | 73 |   | of the path being examined, and then click the ''View changes'' | 
          
          
            | 74 |   | button. | 
          
          
            |   | 66 | Often you'll want to look at changes made on a file  | 
          
          
            |   | 67 | or on a directory spanning multiple revisions. The easiest way | 
          
          
            |   | 68 | to get there is from the TracRevisionLog, where you can select | 
          
          
            |   | 69 | the ''old'' and the ''new'' revisions of the file or directory, and | 
          
          
            |   | 70 | then click the ''View changes'' button. | 
          
        
        
          
            | 78 |   | One of the main feature of source configuration management | 
          
          
            | 79 |   | systems is the possibility to work simultaneously on alternate | 
          
          
            | 80 |   | ''Lines of Developments'', or ''branches''.  | 
          
          
            | 81 |   | The evolution of branches are often made in parallel, making it | 
          
          
            | 82 |   | sometimes difficult to understand the exact set of differences  | 
          
          
            | 83 |   | between alternative versions. | 
          
          
            |   | 74 | One of the core features of version control systems is the possibility | 
          
          
            |   | 75 | to work simultaneously on different ''Lines of Developments'', commonly | 
          
          
            |   | 76 | called “branches”. Trac enables you to examine the exact differences | 
          
          
            |   | 77 | between such branches. | 
          
        
        
          
            | 85 |   | This is where Trac comes to the rescue:  | 
          
          
            | 86 |   | the '''View changes ...''' button in the TracBrowser | 
          
          
            | 87 |   | leads to a form permitting the selection of arbitrary | 
          
          
            | 88 |   | ''From:'' and ''To:'' path/revision pairs. | 
          
          
            |   | 79 | Using the '''View changes ...''' button in the TracBrowser allows you to enter | 
          
          
            |   | 80 | ''From:'' and ''To:'' path/revision pairs. The resulting set of differences consist | 
          
          
            |   | 81 | of the changes that should be applied to the ''From:'' content in order | 
          
          
            |   | 82 | to get to the ''To:'' content. | 
          
        
        
          
            | 90 |   | The resulting set of differences consist in the changes  | 
          
          
            | 91 |   | that should be applied to the ''From:'' content in order | 
          
          
            | 92 |   | to make it look like the ''To:'' content. | 
          
          
            | 93 |   |  | 
          
          
            | 94 |   | For convenience, it is possible to invert the roles | 
          
          
            | 95 |   | of the '''old''' and the '''new''' path/revision pairs | 
          
          
            | 96 |   | by clicking the ''Reverse Diff'' link on the changeset page. | 
          
          
            |   | 84 | For convenience, it is possible to invert the roles of the ''old'' and the ''new'' | 
          
          
            |   | 85 | path/revision pairs by clicking the ''Reverse Diff'' link on the changeset page. | 
          
        
        
          
            | 104 |   | This shows the last change that happened on that path. | 
          
          
            | 105 |   | The links ''Previous Changeset'' and ''Next Changeset'' | 
          
          
            | 106 |   | are replace by links to ''Previous Change'' and ''Next Change'', | 
          
          
            | 107 |   | which makes it really convenient to traverse the change history | 
          
          
            | 108 |   | of a specific file or directory. | 
          
          
            | 109 |   | This view of a changeset, restricted to a specific path, | 
          
          
            | 110 |   | is called ''restricted changeset''. | 
          
          
            | 111 |   |  | 
          
          
            | 112 |   | Of course, if one is doing that on the root of the | 
          
          
            | 113 |   | repository, there will be no path restriction | 
          
          
            | 114 |   | and the full changeset will be shown. | 
          
          
            | 115 |   |  | 
          
          
            |   | 92 | This link will take you to the last change that was made on that path. | 
          
          
            |   | 93 | From there, you can use the ''Previous Change'' and ''Next Change'' links | 
          
          
            |   | 94 | to traverse the change history of the file or directory. |