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index 2c5467057abbfc5af50e4450b869cfd03e4c9520..660904686c656fd00078aa272d0b9a5a198e1833 100644 (file)
the one shown above because the commit object records the time when
it was created and the name of the person performing the commit.
-We can ask git about this particular object with the cat-file
+We can ask git about this particular object with the `cat-file`
command. Don't copy the 40 hex digits from this example but use those
from your own version. Note that you can shorten it to only a few
characters to save yourself typing all 40 hex digits:
The index file
--------------
-The primary tool we've been using to create commits is "git commit
--a", which creates a commit including every change you've made to
+The primary tool we've been using to create commits is `git-commit
+-a`, which creates a commit including every change you've made to
your working tree. But what if you want to commit changes only to
certain files? Or only certain changes to certain files?
+hello world, again
------------------------------------------------
-So "git diff" is comparing against something other than the head.
+So 'git-diff' is comparing against something other than the head.
The thing that it's comparing against is actually the index file,
which is stored in .git/index in a binary format, but whose contents
we can examine with ls-files:
hello world, again
------------------------------------------------
-So what our "git add" did was store a new blob and then put
+So what our 'git-add' did was store a new blob and then put
a reference to it in the index file. If we modify the file again,
-we'll see that the new modifications are reflected in the "git diff"
+we'll see that the new modifications are reflected in the 'git-diff'
output:
------------------------------------------------
+again?
------------------------------------------------
-With the right arguments, git diff can also show us the difference
+With the right arguments, 'git-diff' can also show us the difference
between the working directory and the last commit, or between the
index and the last commit:
+hello world, again
------------------------------------------------
-At any time, we can create a new commit using "git commit" (without
-the -a option), and verify that the state committed only includes the
+At any time, we can create a new commit using 'git-commit' (without
+the "-a" option), and verify that the state committed only includes the
changes stored in the index file, not the additional change that is
still only in our working tree:
+again?
------------------------------------------------
-So by default "git commit" uses the index to create the commit, not
-the working tree; the -a option to commit tells it to first update
+So by default 'git-commit' uses the index to create the commit, not
+the working tree; the "-a" option to commit tells it to first update
the index with all changes in the working tree.
-Finally, it's worth looking at the effect of "git add" on the index
+Finally, it's worth looking at the effect of 'git-add' on the index
file:
------------------------------------------------
$ git add closing.txt
------------------------------------------------
-The effect of the "git add" was to add one entry to the index file:
+The effect of the 'git-add' was to add one entry to the index file:
------------------------------------------------
$ git ls-files --stage
commit" would create a commit that added closing.txt (with its new
contents), but that didn't modify file.txt.
-Also, note that a bare "git diff" shows the changes to file.txt, but
+Also, note that a bare `git diff` shows the changes to file.txt, but
not the addition of closing.txt, because the version of closing.txt
in the index file is identical to the one in the working directory.