Differences From:
File www/branching.wiki part of check-in [dc1a5cf739] - Updates to the branching document. by drh on 2009-01-23 22:05:37. [view]
To:
File www/branching.wiki part of check-in [766bec08ce] - Documentation tweaks. Change the "Setup" menu title to "Admin". Added pages under Admin to view the RCVFROM table of the database. by drh on 2009-01-25 19:18:09. [view]
@@ -81,11 +81,11 @@ <img src="branch03.gif" width=282 height=152><br> Figure 3 </td></tr></table></center> -Check-in 5 is a direct child of check-in 3 because it was created by editing +Check-in 5 is a child of check-in 3 because it was created by editing check-in 3. But check-in 5 also inherits the changes from check-in 4 by -virtual of the merge. So we say that check-in 5 is a <i>merge child</i> +virtue of the merge. So we say that check-in 5 is a <i>merge child</i> of check-in 4 and that it is a <i>direct child</i> of check-in 3. The graph is now back to a single leaf (check-in 5). We have already seen that if fossil is in autosync mode then Bob would @@ -110,11 +110,11 @@ debate. We will simply point out that fossil enables you to do it either way. <h2>Forking Versus Branching</h2> -Forking and having more than one leaf in the check-in tree is usually -considered undesirable, and so forks are usually quickly resolved as -shown in figure 3 above. +Having more than one leaf in the check-in tree is usually +considered undesirable, and so forks are usually either avoided entirely, +as in figure 1, or else quickly resolved as shown in figure 3. But sometimes, one does want to have multiple leaves. For example, a project might have one leaf that is the latest version of the project under development and another leaf that is the latest version that has been tested. @@ -147,9 +147,9 @@ check-ins 9 and 10. In both figures 2 and 4, check-in 2 has two children. In figure 2, we called this a "fork". In diagram 4, we call it a "branch". What is -the difference? As far as the internal fossil data structure are +the difference? As far as the internal fossil data structures are concerned, there is no difference. The distinction is in the intent. In figure 2, the fact that check-in 2 has multiple children is an accident that stems from concurrent development. In figure 4, giving check-in 2 multiple children is a deliberate act. So, to a good @@ -173,17 +173,18 @@ tags as properties with a NULL value. So, tags and properties really are much the same thing, and henceforth we will use the word "tag" to mean either a tag or a property. -A tag can be either a one-time tag or an propagating tag or a cancellation. +A tag can be either a one-time tag or an propagating tag or a cancellation tag. A one-time tag only applies to the check-in to which it is attached. A propagating tag applies to the check-in to which it is attached and also to all direct descendants of that check-in. A <i>direct descendant</i> is a descendant through direct children. Tags propagation does not cross merges. Tag propagation also stops as soon as it encounters another check-in with the same tag. A cancellation tag is attached to a single check-in in order to either override a one-time -tag that was placed on that same check-in, or to block tag propagation. +tag that was previously placed on that same check-in, or to block +tag propagation from an ancestor. Every repository is created with a single empty check-in that has two propagating tags. In figure 5, that initial empty check-in is check-in 1. The <b>branch</b> tag tells (by its value) @@ -215,9 +216,9 @@ check-ins on the trunk go by the symbolic name of "trunk" and check-ins that are on the test branch go by the symbolic name "test". The <b>bgcolor=blue</b> tag on check-in 4 causes the background color -of timelines to be blue for check-in 4 and its descendants. +of timelines to be blue for check-in 4 and its direct descendants. Figure 5 also shows two one-time tags on check-in 9. (The diagram does not make a graphical distinction between one-time and propagating tags.) The <b>sym-release-1.0</b> tag means that check-in 9 can be referred to @@ -232,8 +233,9 @@ <blockquote><dl> <dt><b>Branch</b></dt> <dd><p>A branch is a set of check-ins that have the same value for their +branch property.</p></dd> <dt><b>Leaf</b></dt> <dd><p>A leaf is a check-in that has no children in the same branch.</p></dd> <dt><b>Closed Leaf</b></dt> <dd><p>A closed leaf is leaf that has the <b>closed</b> tag. Such leaves