diff options
authorJunio C Hamano <>2008-08-31 17:41:01 (GMT)
committerJunio C Hamano <>2008-09-01 00:04:56 (GMT)
commite910ce30e41ae4ddc20a64661e8cf2702433e5db (patch)
parente1afaea9427d6b367a3e35b5f2cd7fbfb7148dab (diff)
parentd266a988456fcaab9918eae39f5faf8dcb20cb26 (diff)
Merge branch 'tr/rev-list-docs' into tr/filter-branch
This prepares the necessary parts to merge filter-branch fix based on simplify-merges to master.
4 files changed, 192 insertions, 26 deletions
diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index d7b4114..db16b0c 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -307,9 +307,18 @@ backslash, and zero or more occurrences of `sub` followed by
There are a few built-in patterns to make this easier, and `tex`
is one of them, so you do not have to write the above in your
configuration file (you still need to enable this with the
-attribute mechanism, via `.gitattributes`). Another built-in
-pattern is defined for `java` that defines a pattern suitable
-for program text in Java language.
+attribute mechanism, via `.gitattributes`). The following built in
+patterns are available:
+- `bibtex` suitable for files with BibTeX coded references.
+- `java` suitable for source code in the Java lanugage.
+- `pascal` suitable for source code in the Pascal/Delphi language.
+- `ruby` suitable for source code in the Ruby language.
+- `tex` suitable for source code for LaTeX documents.
Performing a three-way merge
diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt
index 67ff0ea..15752b9 100644
--- a/Documentation/rev-list-options.txt
+++ b/Documentation/rev-list-options.txt
@@ -43,11 +43,13 @@ endif::git-rev-list[]
- Print the parents of the commit.
+ Print the parents of the commit. Also enables parent
+ rewriting, see 'History Simplification' below.
- Print the children of the commit.
+ Print the children of the commit. Also enables parent
+ rewriting, see 'History Simplification' below.
@@ -191,20 +193,6 @@ endif::git-rev-list[]
Stop when a given path disappears from the tree.
- Show also parts of history irrelevant to current state of given
- paths. This turns off history simplification, which removed merges
- which didn't change anything at all at some child. It will still actually
- simplify away merges that didn't change anything at all into either
- child.
- Simplify away commits that did not change the given paths, similar
- to `--full-history`, and further remove merges none of whose
- parent history changes the given paths.
Do not print commits with more than one parent.
@@ -286,18 +274,186 @@ See also linkgit:git-reflog[1].
Output uninteresting commits at the boundary, which are usually
not shown.
+History Simplification
+When optional paths are given, 'git-rev-list' simplifies commits with
+various strategies, according to the options you have selected.
+Suppose you specified `foo` as the <paths>. We shall call commits
+that modify `foo` !TREESAME, and the rest TREESAME. (In a diff
+filtered for `foo`, they look different and equal, respectively.)
+In the following, we will always refer to the same example history to
+illustrate the differences between simplification settings. We assume
+that you are filtering for a file `foo` in this commit graph:
+ .-A---M---N---O---P
+ / / / / /
+ I B C D E
+ \ / / / /
+ `-------------'
+The horizontal line of history A--P is taken to be the first parent of
+each merge. The commits are:
+* `I` is the initial commit, in which `foo` exists with contents
+ "asdf", and a file `quux` exists with contents "quux". Initial
+ commits are compared to an empty tree, so `I` is !TREESAME.
+* In `A`, `foo` contains just "foo".
+* `B` contains the same change as `A`. Its merge `M` is trivial and
+ hence TREESAME to all parents.
+* `C` does not change `foo`, but its merge `N` changes it to "foobar",
+ so it is not TREESAME to any parent.
+* `D` sets `foo` to "baz". Its merge `O` combines the strings from
+ `N` and `D` to "foobarbaz"; i.e., it is not TREESAME to any parent.
+* `E` changes `quux` to "xyzzy", and its merge `P` combines the
+ strings to "quux xyzzy". Despite appearing interesting, `P` is
+ TREESAME to all parents.
+'rev-list' walks backwards through history, including or excluding
+commits based on whether '\--full-history' and/or parent rewriting
+(via '\--parents' or '\--children') are used. The following settings
+are available.
+Default mode::
+ Commits are included if they are not TREESAME to any parent
+ (though this can be changed, see '\--sparse' below). If the
+ commit was a merge, and it was TREESAME to one parent, follow
+ only that parent. (Even if there are several TREESAME
+ parents, follow only one of them.) Otherwise, follow all
+ parents.
+This results in:
+ .-A---N---O
+ / /
+ I---------D
+Note how the rule to only follow the TREESAME parent, if one is
+available, removed `B` from consideration entirely. `C` was
+considered via `N`, but is TREESAME. Root commits are compared to an
+empty tree, so `I` is !TREESAME.
+Parent/child relations are only visible with --parents, but that does
+not affect the commits selected in default mode, so we have shown the
+parent lines.
+--full-history without parent rewriting::
+ This mode differs from the default in one point: always follow
+ all parents of a merge, even if it is TREESAME to one of them.
+ Even if more than one side of the merge has commits that are
+ included, this does not imply that the merge itself is! In
+ the example, we get
+ I A B N D O
+`P` and `M` were excluded because they are TREESAME to a parent. `E`,
+`C` and `B` were all walked, but only `B` was !TREESAME, so the others
+do not appear.
+Note that without parent rewriting, it is not really possible to talk
+about the parent/child relationships between the commits, so we show
+them disconnected.
+--full-history with parent rewriting::
+ Ordinary commits are only included if they are !TREESAME
+ (though this can be changed, see '\--sparse' below).
+Merges are always included. However, their parent list is rewritten:
+Along each parent, prune away commits that are not included
+themselves. This results in
+ .-A---M---N---O---P
+ / / / / /
+ I B / D /
+ \ / / / /
+ `-------------'
+Compare to '\--full-history' without rewriting above. Note that `E`
+was pruned away because it is TREESAME, but the parent list of P was
+rewritten to contain `E`'s parent `I`. The same happened for `C` and
+`N`. Note also that `P` was included despite being TREESAME.
+In addition to the above settings, you can change whether TREESAME
+affects inclusion:
+ Commits that are walked are included if they are not TREESAME
+ to any parent.
-When optional paths are given, the default behaviour ('--dense') is to
-only output commits that changes at least one of them, and also ignore
-merges that do not touch the given paths.
+ All commits that are walked are included.
+Note that without '\--full-history', this still simplifies merges: if
+one of the parents is TREESAME, we follow only that one, so the other
+sides of the merge are never walked.
+Finally, there is a fourth simplification mode available:
-Use the '--sparse' flag to makes the command output all eligible commits
-(still subject to count and age limitation), but apply merge
-simplification nevertheless.
+ First, build a history graph in the same way that
+ '\--full-history' with parent rewriting does (see above).
+Then simplify each commit `C` to its replacement `C'` in the final
+history according to the following rules:
+* Set `C'` to `C`.
+* Replace each parent `P` of `C'` with its simplification `P'`. In
+ the process, drop parents that are ancestors of other parents, and
+ remove duplicates.
+* If after this parent rewriting, `C'` is a root or merge commit (has
+ zero or >1 parents), a boundary commit, or !TREESAME, it remains.
+ Otherwise, it is replaced with its only parent.
+The effect of this is best shown by way of comparing to
+'\--full-history' with parent rewriting. The example turns into:
+ .-A---M---N---O
+ / / /
+ I B D
+ \ / /
+ `---------'
+Note the major differences in `N` and `P` over '\--full-history':
+* `N`'s parent list had `I` removed, because it is an ancestor of the
+ other parent `M`. Still, `N` remained because it is !TREESAME.
+* `P`'s parent list similarly had `I` removed. `P` was then
+ removed completely, because it had one parent and is TREESAME.
+Bisection Helpers
Limit output to the one commit object which is roughly halfway between
@@ -347,7 +503,6 @@ after all the sorted commit objects, there will be the same text as if
`--bisect-vars` had been used alone.
Commit Ordering
diff --git a/daemon.c b/daemon.c
index 4540e8d..8dcde73 100644
--- a/daemon.c
+++ b/daemon.c
@@ -794,6 +794,7 @@ static void child_handler(int signo)
+ signal(SIGCHLD, child_handler);
static int set_reuse_addr(int sockfd)
diff --git a/diff.c b/diff.c
index 6954f99..bf5d5f1 100644
--- a/diff.c
+++ b/diff.c
@@ -1387,6 +1387,7 @@ static struct builtin_funcname_pattern {
"^\\(.*=[ \t]*\\(class\\|record\\).*\\)$"
+ { "bibtex", "\\(@[a-zA-Z]\\{1,\\}[ \t]*{\\{0,1\\}[ \t]*[^ \t\"@',\\#}{~%]*\\).*$" },
{ "tex", "^\\(\\\\\\(\\(sub\\)*section\\|chapter\\|part\\)\\*\\{0,1\\}{.*\\)$" },
{ "ruby", "^\\s*\\(\\(class\\|module\\|def\\)\\s.*\\)$" },