Git Diff Index

git-diff-index(1) ================= NAME ---- git-diff-index - Compare a tree to the working tree or index SYNOPSIS -------- [verse] 'git diff-index' [-m] [--cached] [--merge-base] [<common-diff-options>] <tree-ish> [<path>...] DESCRIPTION ----------- Compare the content and mode of the blobs found in a tree object with the corresponding tracked files in the working tree, or with the corresponding paths in the index. When <path> arguments are present, compare only paths matching those patterns. Otherwise all tracked files are compared. OPTIONS ------- include::diff-options.adoc[] <tree-ish>:: The id of a tree object to diff against. --cached:: Do not consider the on-disk file at all. --merge-base:: Instead of comparing <tree-ish> directly, use the merge base between <tree-ish> and HEAD instead. <tree-ish> must be a commit. -m:: By default, files recorded in the index but not checked out are reported as deleted. This flag makes 'git diff-index' say that all non-checked-out files are up to date. include::diff-format.adoc[] OPERATING MODES --------------- You can choose whether you want to trust the index file entirely (using the `--cached` flag) or ask the diff logic to show any files that don't match the stat state as being "tentatively changed". Both of these operations are very useful indeed. CACHED MODE ----------- If `--cached` is specified, it allows you to ask: show me the differences between HEAD and the current index contents (the ones I'd write using 'git write-tree') For example, let's say that you have worked on your working directory, updated some files in the index and are ready to commit. You want to see exactly *what* you are going to commit, without having to write a new tree object and compare it that way, and to do that, you just do git diff-index --cached HEAD Example: let's say I had renamed `commit.c` to `git-commit.c`, and I had done an `update-index` to make that effective in the index file. `git diff-files` wouldn't show anything at all, since the index file matches my working directory. But doing a 'git diff-index' does: torvalds@ppc970:~/git> git diff-index --cached HEAD :100644 000000 4161aecc6700a2eb579e842af0b7f22b98443f74 0000000000000000000000000000000000000000 D commit.c :000000 100644 0000000000000000000000000000000000000000 4161aecc6700a2eb579e842af0b7f22b98443f74 A git-commit.c You can see easily

The git diff-index command compares a tree object to the working tree or index, showing differences in content and mode of blobs, with options to consider or ignore on-disk files and filter results by path patterns.