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@@ -279,6 +279,94 @@ few exceptions. Even though...
catch potential problems early, safety triggers.
+Git recognizes files encoded in ASCII or one of its supersets (e.g.
+UTF-8, ISO-8859-1, ...) as text files. Files encoded in certain other
+encodings (e.g. UTF-16) are interpreted as binary and consequently
+built-in Git text processing tools (e.g. 'git diff') as well as most Git
+web front ends do not visualize the contents of these files by default.
+In these cases you can tell Git the encoding of a file in the working
+directory with the `working-tree-encoding` attribute. If a file with this
+attribute is added to Git, then Git reencodes the content from the
+specified encoding to UTF-8. Finally, Git stores the UTF-8 encoded
+content in its internal data structure (called "the index"). On checkout
+the content is reencoded back to the specified encoding.
+Please note that using the `working-tree-encoding` attribute may have a
+number of pitfalls:
+- Alternative Git implementations (e.g. JGit or libgit2) and older Git
+ versions (as of March 2018) do not support the `working-tree-encoding`
+ attribute. If you decide to use the `working-tree-encoding` attribute
+ in your repository, then it is strongly recommended to ensure that all
+ clients working with the repository support it.
+ For example, Microsoft Visual Studio resources files (`*.rc`) or
+ PowerShell script files (`*.ps1`) are sometimes encoded in UTF-16.
+ If you declare `*.ps1` as files as UTF-16 and you add `foo.ps1` with
+ a `working-tree-encoding` enabled Git client, then `foo.ps1` will be
+ stored as UTF-8 internally. A client without `working-tree-encoding`
+ support will checkout `foo.ps1` as UTF-8 encoded file. This will
+ typically cause trouble for the users of this file.
+ If a Git client, that does not support the `working-tree-encoding`
+ attribute, adds a new file `bar.ps1`, then `bar.ps1` will be
+ stored "as-is" internally (in this example probably as UTF-16).
+ A client with `working-tree-encoding` support will interpret the
+ internal contents as UTF-8 and try to convert it to UTF-16 on checkout.
+ That operation will fail and cause an error.
+- Reencoding content to non-UTF encodings can cause errors as the
+ conversion might not be UTF-8 round trip safe. If you suspect your
+ encoding to not be round trip safe, then add it to
+ `core.checkRoundtripEncoding` to make Git check the round trip
+ encoding (see linkgit:git-config[1]). SHIFT-JIS (Japanese character
+ set) is known to have round trip issues with UTF-8 and is checked by
+ default.
+- Reencoding content requires resources that might slow down certain
+ Git operations (e.g 'git checkout' or 'git add').
+Use the `working-tree-encoding` attribute only if you cannot store a file
+in UTF-8 encoding and if you want Git to be able to process the content
+as text.
+As an example, use the following attributes if your '*.ps1' files are
+UTF-16 encoded with byte order mark (BOM) and you want Git to perform
+automatic line ending conversion based on your platform.
+*.ps1 text working-tree-encoding=UTF-16
+Use the following attributes if your '*.ps1' files are UTF-16 little
+endian encoded without BOM and you want Git to use Windows line endings
+in the working directory. Please note, it is highly recommended to
+explicitly define the line endings with `eol` if the `working-tree-encoding`
+attribute is used to avoid ambiguity.
+*.ps1 text working-tree-encoding=UTF-16LE eol=CRLF
+You can get a list of all available encodings on your platform with the
+following command:
+iconv --list
+If you do not know the encoding of a file, then you can use the `file`
+command to guess the encoding:
+file foo.ps1