Reorganize the code in `truncate.rs` into three distinct functions
representing the three modes of operation of the `truncate` program. The
three modes are
- `truncate -r RFILE FILE`, which sets the length of `FILE` to match the
length of `RFILE`,
- `truncate -r RFILE -s NUM FILE`, which sets the length of `FILE`
relative to the given `RFILE`,
- `truncate -s NUM FILE`, which sets the length of `FILE` either
absolutely or relative to its curent length.
This organization of the code makes it more concise and easier to
follow.
Create a method that computes the final target size in bytes for the
file to truncate, given the reference file size and the parameter to the
`TruncateMode`.
Add a helper function to contain the code for parsing the size and the
modifier symbol, if any. This commit also changes the `TruncateMode`
enum so that the parameter for each "mode" is stored along with the
enumeration value. This is because the parameter has a different meaning
in each mode.
Remove "read" permissions from the `OpenOptions` when opening a new file
just to truncate it. We will never read from the file, only write to
it. (Specifically, we will only call `File::set_len()`.)
* add "clippy.toml" in order to set MSRV for clippy linting
this works only if clippy is invoked with "+nightly"
* add "--target" to clippy in order to also lint tests
* sort: crash when failing to open an input file
Instead of ignoring files we fail to open, crash.
The error message does not exactly match gnu, but that would require
more effort.
* use split_whitespace instead of a manual implementation
* fix expected error on windows
* sort: update expected error message
* sort: disable support for thousand separators
In order to be compatible with GNU, we have to disable thousands
separators. GNU does not enable them for the C locale, either.
Once we add support for locales we can add this feature back.
* sort: delete unused fixtures
* sort: compare -0 and 0 equal
I must have misunderstood this when implementing, but GNU considers
-0, 0, and invalid numbers to be equal.
* sort: strip blanks before applying the char index
* sort: don't crash when key start is after key end
* sort: add "no match" for months at the first non-whitespace char
We should put the "^ no match for key" indicator at the first
non-whitespace character of a field.
* sort: improve support for e notation
* sort: use maches! macros
