X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=Documentation%2Fgit-read-tree.txt;h=8b91847856b51fbe6727ad96e6d5e4d1fd00c815;hb=27dedf0;hp=e1be6cc0bcfded709bbd57a3ccd73e5ed241dd18;hpb=e8c80638abc99928dba9ac832589749a531e2e21;p=git.git diff --git a/Documentation/git-read-tree.txt b/Documentation/git-read-tree.txt index e1be6cc0b..8b9184785 100644 --- a/Documentation/git-read-tree.txt +++ b/Documentation/git-read-tree.txt @@ -1,24 +1,23 @@ git-read-tree(1) ================ -v0.1, May 2005 NAME ---- -git-read-tree - Reads tree information into the directory cache +git-read-tree - Reads tree information into the index SYNOPSIS -------- -'git-read-tree' ( | [-m [-u]] [ []]) +'git-read-tree' ( | [-m [-u|-i]] [ []]) DESCRIPTION ----------- -Reads the tree information given by into the directory cache, +Reads the tree information given by into the index, but does not actually *update* any of the files it "caches". (see: -git-checkout-cache) +git-checkout-index) -Optionally, it can merge a tree into the cache, perform a +Optionally, it can merge a tree into the index, perform a fast-forward (i.e. 2-way) merge, or a 3-way merge, with the -m flag. When used with -m, the -u flag causes it to also update the files in the work tree with the result of the merge. @@ -31,10 +30,24 @@ OPTIONS -m:: Perform a merge, not just a read. +--reset:: + + Same as -m except that unmerged entries will be silently ignored. + -u:: After a successful merge, update the files in the work tree with the result of the merge. +-i:: + Usually a merge requires the index file as well as the + files in the working tree are up to date with the + current head commit, in order not to lose local + changes. This flag disables the check with the working + tree and is meant to be used when creating a merge of + trees that are not directly related to the current + working tree status into a temporary index file. + + :: The id of the tree object(s) to be read/merged. @@ -50,13 +63,13 @@ provided. Single Tree Merge ~~~~~~~~~~~~~~~~~ If only 1 tree is specified, git-read-tree operates as if the user did not -specify '-m', except that if the original cache has an entry for a +specify '-m', except that if the original index has an entry for a given pathname, and the contents of the path matches with the tree -being read, the stat info from the cache is used. (In other words, the -cache's stat()s take precedence over the merged tree's). +being read, the stat info from the index is used. (In other words, the +index's stat()s take precedence over the merged tree's). That means that if you do a "git-read-tree -m " followed by a -"git-checkout-cache -f -u -a", the "git-checkout-cache" only checks out +"git-checkout-index -f -u -a", the "git-checkout-index" only checks out the stuff that really changed. This is used to avoid unnecessary false hits when "git-diff-files" is @@ -74,10 +87,10 @@ fast forward situation). When two trees are specified, the user is telling git-read-tree the following: - (1) The current index and work tree is derived from $H, but + 1. The current index and work tree is derived from $H, but the user may have local changes in them since $H; - (2) The user wants to fast-forward to $M. + 2. The user wants to fast-forward to $M. In this case, the "git-read-tree -m $H $M" command makes sure that no local change is lost as the result of this "merge". @@ -87,7 +100,7 @@ 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 cache + 2 nothing exists nothing remove path from index 3 nothing exists exists use M clean I==H I==M @@ -100,7 +113,7 @@ Here are the "carry forward" rules: 8 yes N/A no nothing exists fail 9 no N/A no nothing exists fail - 10 yes yes N/A exists nothing remove path from cache + 10 yes yes N/A exists nothing remove path from index 11 no yes N/A exists nothing fail 12 yes no N/A exists nothing fail 13 no no N/A exists nothing fail @@ -119,20 +132,20 @@ Here are the "carry forward" rules: 20 yes yes no exists exists use M 21 no yes no exists exists fail -In all "keep index" cases, the cache entry stays as in the +In all "keep index" cases, the index entry stays as in the original index file. If the entry were not up to date, git-read-tree keeps the copy in the work tree intact when operating under the -u flag. When this form of git-read-tree returns successfully, you can see what "local changes" you made are carried forward by running -"git-diff-cache --cached $M". Note that this does not -necessarily match "git-diff-cache --cached $H" would have +"git-diff-index --cached $M". Note that this does not +necessarily match "git-diff-index --cached $H" would have produced before such a two tree merge. This is because of cases 18 and 19 --- if you already had the changes in $M (e.g. maybe -you picked it up via e-mail in a patch form), "git-diff-cache +you picked it up via e-mail in a patch form), "git-diff-index --cached $H" would have told you about the change before this -merge, but it would not show in "git-diff-cache --cached $M" +merge, but it would not show in "git-diff-index --cached $M" output after two-tree merge. @@ -205,8 +218,8 @@ populated. Here is an outline of how the algorithm works: matching "stage1" entry if it exists too. .. all the normal trivial rules .. -You would normally use "git-merge-cache" with supplied -"git-merge-one-file-script" to do this last step. The script +You would normally use "git-merge-index" with supplied +"git-merge-one-file" to do this last step. The script does not touch the files in the work tree, and the entire merge happens in the index file. In other words, there is no need to worry about what is in the working directory, since it is never @@ -224,23 +237,23 @@ This is done to prevent you from losing your work-in-progress changes. To illustrate, suppose you start from what has been commited last to your repository: - $ JC=`cat .git/HEAD` - $ git-checkout-cache -f -u -a $JC + $ JC=`git-rev-parse --verify "HEAD^0"` + $ git-checkout-index -f -u -a $JC -You do random edits, without running git-update-cache. And then +You do random edits, without running git-update-index. And then you notice that the tip of your "upstream" tree has advanced since you pulled from him: - $ git-fetch-script rsync://.... linus + $ git-fetch rsync://.... linus $ LT=`cat .git/MERGE_HEAD` Your work tree is still based on your HEAD ($JC), but you have some edits since. Three-way merge makes sure that you have not -added or modified cache entries since $JC, and if you haven't, +added or modified index entries since $JC, and if you haven't, then does the right thing. So with the following sequence: $ git-read-tree -m -u `git-merge-base $JC $LT` $JC $LT - $ git-merge-cache git-merge-one-file-script -a + $ git-merge-index git-merge-one-file -a $ echo "Merge with Linus" | \ git-commit-tree `git-write-tree` -p $JC -p $LT @@ -251,7 +264,7 @@ updated to the result of the merge. See Also -------- -link:git-write-tree.html[git-write-tree]; link:git-ls-files.html[git-ls-files] +gitlink:git-write-tree[1]; gitlink:git-ls-files[1] Author @@ -264,5 +277,5 @@ Documentation by David Greaves, Junio C Hamano and the git-list