I read through every file and applied a couple of rustfmt suggestions. The brace placement and alignment of items on similar lines has been made consistent, even if neither are rustfmt's default style (a file has been put in place to enforce this). Other changes are:
• Alphabetical imports and modules
• Comma placement at the end of match blocks
• Use newlines and indentation judiciously
• Spaces around associated types
• Spaces after negations (it makes it more clear imho)
• Comment formatting
• Use early-returns and Optional `?` where appropriate
This commit uses Clippy to fix all the 'use_self' warnings. Using Self instead of the type name has been good Rust style for a while now, and it's become the style I'm used to seeing.
exa deals with cells and widths a lot: the items in a grid need to be aligned according to their *contents’* widths, rather than the length of their strings, which often included ANSI escape characters. As an optimisation, it used to calculate this separately based on the filename, and dealing with any extra characters (such as the classify ones) in that function too.
Recently, though, file names have become a lot more complicated. Classification added zero to one extra characters, and now with escaped control characters in file names, it’s not so easy to calculate the display width of a filename.
This commit removes the function that calculated the width, in favour of building the output string (it’s going to be displayed anyway) and just getting the width of what it displays instead.
The benefit of this is that it make it possible to convert text cell contents
vectors into text cells with a method (see next commit). Casualties include
having to call `.into()` on vectors everywhere, which I'm not convinced is a
bad thing.
Because, strictly speaking, it's not a length, it's a width!
Also, re-order some struct constructors so that they're no longer
order-dependent (it's no longer the case that a value will be borrowed for one
field then consumed in another, meaning they have to be ordered in a certain
way to compile. Now the value is just worked out beforehand and the fields can
be specified in any order)
This commit introduces the `output::cell::DisplayWidth` struct, which
encapsulates the Unicode *display width* of a string in a struct that makes it
less easily confused with the *length* of a string.
The use of this type means that it's now harder to accidentally use a string's
length-in-bytes as its width. I've fixed at least one case in the code where
this was being done!
The only casualty is that it introduces a dependency on the output module from
the file module, which will be removed next commit.
A recent change to ansi-term [1] means that `ANSIString`s can now hold either
owned *or* borrowed data (Rust calls this the Cow type). This means that we
can delay formatting ANSIStrings into ANSI-control-code-formatted strings
until it's absolutely necessary. The process for doing this was:
1. Replace the `Cell` type with a `TextCell` type that holds a vector of
`ANSIString` values instead of a formatted string. It still does the
width tracking.
2. Rework the details module's `render` functions to emit values of this
type.
3. Similarly, rework the functions that produce cells containing filenames
to use a `File` value's `name` field, which is an owned `String` that
can now be re-used.
4. Update the printing, formatting, and width-calculating code in the
details and grid-details views to produce a table by adding vectors
together instead of adding strings together, delaying the formatting as
long as it can.
This results in fewer allocations (as fewer `String` values are produced), and
makes the API tidier (as fewer `String` values are being passed around without
having their contents specified).
This also paves the way to Windows support, or at least support for
non-ANSI terminals: by delaying the time until strings are formatted,
it'll now be easier to change *how* they are formatted.
Casualties include:
- Bump to ansi_term v0.7.1, which impls `PartialEq` and `Debug` on
`ANSIString`.
- The grid_details and lines views now need to take a vector of files, rather
than a borrowed slice, so the filename cells produced now own the filename
strings that get taken from files.
- Fixed the signature of `File#link_target` to specify that the
file produced refers to the same directory, rather than some phantom
directory with the same lifetime as the file. (This was wrong from the
start, but it broke nothing until now)
References:
[1]: ansi-term@f6a6579ba8174de1cae64d181ec04af32ba2a4f0
