git2r (version 0.33.0)

diff.git_repository: Changes between commits, trees, working tree, etc.

Description

Changes between commits, trees, working tree, etc.

Usage

# S3 method for git_repository
diff(
  x,
  index = FALSE,
  as_char = FALSE,
  filename = NULL,
  context_lines = 3,
  interhunk_lines = 0,
  old_prefix = "a",
  new_prefix = "b",
  id_abbrev = NULL,
  path = NULL,
  max_size = NULL,
  ...
)
# S3 method for git_tree
diff(
  x,
  new_tree = NULL,
  index = FALSE,
  as_char = FALSE,
  filename = NULL,
  context_lines = 3,
  interhunk_lines = 0,
  old_prefix = "a",
  new_prefix = "b",
  id_abbrev = NULL,
  path = NULL,
  max_size = NULL,
  ...
)

Value

A git_diff object if as_char is FALSE. If as_char is TRUE and filename is NULL, a character string, else NULL.

Arguments

x

A git_repository object or the old git_tree object to compare to.

index

When object equals a git_repository

Whether to compare the index to HEAD. If FALSE (the default), then the working tree is compared to the index.

When object equals a git_tree

Whether to use the working directory (by default), or the index (if set to TRUE) in the comparison to object.

as_char

logical: should the result be converted to a character string?. Default is FALSE.

filename

If as_char is TRUE, then the diff can be written to a file with name filename (the file is overwritten if it exists). Default is NULL.

context_lines

The number of unchanged lines that define the boundary of a hunk (and to display before and after). Defaults to 3.

interhunk_lines

The maximum number of unchanged lines between hunk boundaries before the hunks will be merged into one. Defaults to 0.

old_prefix

The virtual "directory" prefix for old file names in hunk headers. Default is "a".

new_prefix

The virtual "directory" prefix for new file names in hunk headers. Defaults to "b".

id_abbrev

The abbreviation length to use when formatting object ids. Defaults to the value of 'core.abbrev' from the config, or 7 if NULL.

path

A character vector of paths / fnmatch patterns to constrain diff. Default is NULL which include all paths.

max_size

A size (in bytes) above which a blob will be marked as binary automatically; pass a negative value to disable. Defaults to 512MB when max_size is NULL.

...

Not used.

new_tree

The new git_tree object to compare, or NULL. If NULL, then we use the working directory or the index (see the index argument).

Line endings

Different operating systems handle line endings differently. Windows uses both a carriage-return character and a linefeed character to represent a newline in a file. While Linux and macOS use only the linefeed character for a newline in a file. To avoid problems in your diffs, you can configure Git to properly handle line endings using the core.autocrlf setting in the Git config file, see the Git documentation (https://git-scm.com/).

Examples

if (FALSE) {
## Initialize a repository
path <- tempfile(pattern="git2r-")
dir.create(path)
repo <- init(path)

## Config user
config(repo, user.name = "Alice", user.email = "[e-mail]")

## Create a file, add, commit
writeLines("Hello world!", file.path(path, "test.txt"))
add(repo, "test.txt")
commit(repo, "Commit message")

## Change the file
writeLines(c("Hello again!", "Here is a second line", "And a third"),
           file.path(path, "test.txt"))

## diff between index and workdir
diff_1 <- diff(repo)
summary(diff_1)
cat(diff(repo, as_char=TRUE))

## Diff between index and HEAD is empty
diff_2 <- diff(repo, index=TRUE)
summary(diff_2)
cat(diff(repo, index=TRUE, as_char=TRUE))

## Diff between tree and working dir, same as diff_1
diff_3 <- diff(tree(commits(repo)[[1]]))
summary(diff_3)
cat(diff(tree(commits(repo)[[1]]), as_char=TRUE))

## Add changes, diff between index and HEAD is the same as diff_1
add(repo, "test.txt")
diff_4 <- diff(repo, index=TRUE)
summary(diff_4)
cat(diff(repo, index=TRUE, as_char=TRUE))

## Diff between tree and index
diff_5 <- diff(tree(commits(repo)[[1]]), index=TRUE)
summary(diff_5)
cat(diff(tree(commits(repo)[[1]]), index=TRUE, as_char=TRUE))

## Diff between two trees
commit(repo, "Second commit")
tree_1 <- tree(commits(repo)[[2]])
tree_2 <- tree(commits(repo)[[1]])
diff_6 <- diff(tree_1, tree_2)
summary(diff_6)
cat(diff(tree_1, tree_2, as_char=TRUE))

## Binary files
set.seed(42)
writeBin(as.raw((sample(0:255, 1000, replace=TRUE))),
         con=file.path(path, "test.bin"))
add(repo, "test.bin")
diff_7 <- diff(repo, index=TRUE)
summary(diff_7)
cat(diff(repo, index=TRUE, as_char=TRUE))
}