Merge branch 'jc/maint-checkout-keep-remove' into maint

gitster · gitster · commit 2ba3d5d9bd47 · 2008-09-18T19:53:22.000-07:00
* jc/maint-checkout-keep-remove:
  checkout: do not lose staged removal
diff --git a/Documentation/git-read-tree.txt b/Documentation/git-read-tree.txt
@@ -160,7 +160,10 @@ Here are the "carry forward" rules:
       0 nothing             nothing  nothing  (does not happen)
       1 nothing             nothing  exists   use M
       2 nothing             exists   nothing  remove path from index
-      3 nothing             exists   exists   use M
+      3 nothing             exists   exists,  use M if "initial checkout"
+				     H == M   keep index otherwise
+				     exists   fail
+				     H != M
 
         clean I==H  I==M
        ------------------
@@ -207,6 +210,12 @@ you picked it up via e-mail in a patch form), `git diff-index
 merge, but it would not show in `git diff-index --cached $M`
 output after two-tree merge.
 
+Case #3 is slightly tricky and needs explanation.  The result from this
+rule logically should be to remove the path if the user staged the removal
+of the path and then swiching to a new branch.  That however will prevent
+the initial checkout from happening, so the rule is modified to use M (new
+tree) only when the contents of the index is empty.  Otherwise the removal
+of the path is kept as long as $H and $M are the same.
 
 3-Way Merge
 ~~~~~~~~~~~
diff --git a/builtin-checkout.c b/builtin-checkout.c
@@ -269,6 +269,8 @@ static int merge_working_tree(struct checkout_opts *opts,
 		}
 
 		/* 2-way merge to the new branch */
+		topts.initial_checkout = (!active_nr &&
+					  (old->commit == new->commit));
 		topts.update = 1;
 		topts.merge = 1;
 		topts.gently = opts->merge;
diff --git a/builtin-read-tree.c b/builtin-read-tree.c
@@ -206,6 +206,7 @@ int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
 			break;
 		case 2:
 			opts.fn = twoway_merge;
+			opts.initial_checkout = !active_nr;
 			break;
 		case 3:
 		default:
diff --git a/unpack-trees.c b/unpack-trees.c
@@ -941,8 +941,17 @@ int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
 			return -1;
 		}
 	}
-	else if (newtree)
+	else if (newtree) {
+		if (oldtree && !o->initial_checkout) {
+			/*
+			 * deletion of the path was staged;
+			 */
+			if (same(oldtree, newtree))
+				return 1;
+			return reject_merge(oldtree, o);
+		}
 		return merged_entry(newtree, current, o);
+	}
 	return deleted_entry(oldtree, current, o);
 }
 
diff --git a/unpack-trees.h b/unpack-trees.h
@@ -26,6 +26,7 @@ struct unpack_trees_options {
 		     verbose_update:1,
 		     aggressive:1,
 		     skip_unmerged:1,
+		     initial_checkout:1,
 		     gently:1;
 	const char *prefix;
 	int pos;

Original file line number	Diff line number	Diff line change
`@@ -269,6 +269,8 @@ static int merge_working_tree(struct checkout_opts *opts,`
`269`	`269`	`}`
`270`	`270`
`271`	`271`	`/* 2-way merge to the new branch */`
	`272`	`+ topts.initial_checkout = (!active_nr &&`
	`273`	`+ (old->commit == new->commit));`
`272`	`274`	`topts.update = 1;`
`273`	`275`	`topts.merge = 1;`
`274`	`276`	`topts.gently = opts->merge;`
Original file line number	Diff line number	Diff line change
`@@ -941,8 +941,17 @@ int twoway_merge(struct cache_entry *src, struct unpack_trees_options o)`
`941`	`941`	`return -1;`
`942`	`942`	`}`
`943`	`943`	`}`
`944`		`- else if (newtree)`
	`944`	`+ else if (newtree) {`
	`945`	`+ if (oldtree && !o->initial_checkout) {`
	`946`	`+ /*`
	`947`	`+ * deletion of the path was staged;`
	`948`	`+ */`
	`949`	`+ if (same(oldtree, newtree))`
	`950`	`+ return 1;`
	`951`	`+ return reject_merge(oldtree, o);`
	`952`	`+ }`
`945`	`953`	`return merged_entry(newtree, current, o);`
	`954`	`+ }`
`946`	`955`	`return deleted_entry(oldtree, current, o);`
`947`	`956`	`}`
`948`	`957`