This makes pickaxe more intelligent than the classic blame.
A typical example is a change that moves one static C function
from lower part of the file to upper part of the same file,
because you added a new caller in the middle.
The versions in the parent and the child would look like this:
parent child
A static foo() {
B ...
C }
D A
E B
F C
G D
static foo() { ... call foo();
... E
} F
H G
H
With the classic blame algorithm, we can blame lines A B C D E F
G and H to the parent. The child is guilty of introducing the
line "... call foo();", and the blame is placed on the child.
However, the classic blame algorithm fails to notice that the
implementation of foo() at the top of the file is not new, and
moved from the lower part of the parent.
This commit introduces detection of such line movements, and
correctly blames the lines that were simply moved in the file to
the parent.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Currently it does what git-blame does, but only faster.
More importantly, its internal structure is designed to support
content movement (aka cut-and-paste) more easily by allowing
more than one paths to be taken from the same commit.
Signed-off-by: Junio C Hamano <junkio@cox.net>
