Add Rust tool layer

Author: rene-descartes2021

layers/+tools/fzf/README.md

@@ -27,6 +27,8 @@ choco install ag
 choco install ripgrep
 ```
 
+Alternatively ripgrep, fd, git-delta, bat will be built from source if using the 'rustc' layer. fzf and ag are not rust and can't be built with the 'rustc' layer.
+
 ## Install
 
 To use this configuration layer, add it to your `~/.spacevim`. *It has been enabled as one of the default layers*.

layers/+tools/rustc/README.md

@@ -0,0 +1,43 @@
+# Rust tool layer
+
+## Table of Contents
+
+<!-- TOC GFM -->
+
+* [Description](#description)
+* [Install](#install)
+  * [Building](#building)
+     * [Prerequisite](#prerequisite)
+     * [MS Windows](#ms-windows)
+
+<!-- /TOC -->
+
+## Description
+
+Folowing the zero-install philosophy, this layer adds the Rust compiler, standard library, documentation, and default extensions including Cargo. All built from source.
+
+If `rustc` is found on $PATH, or $RUSTC points to `rustc`, and either is of sufficient version, that will be used instead of building from source.
+
+Cargo will be added to $PATH for use by Vim plugins and for a LSP plugin/engine to install language servers.
+
+A convenience feature of this layer is that the binaries installed by cargo will be added to $PATH, e.g. deno, tree-sitter, and language servers.
+
+## Install
+
+To use this layer, add it to your `~/.spacevim`.
+
+### Building
+
+On building from source, around 600MiB is іnstalled into the prefix `./install` relative to the plugin directory. The building process requires around 17GiB, which will be deleted on completion.
+
+If the automated building doesn't work, you may navigate to the plugin directory and build manually, into the prefix `./install`; installing system-wide isn't required. Or install prebuilt binaries and set $PATH or $RUSTC accordingly.
+
+#### Prerequisite
+
+See [Unix](https://github.com/rust-lang/rust#building-on-a-unix-like-system) or [Windows](https://github.com/rust-lang/rust#building-on-windows) prerequisites.
+
+#### MS Windows
+
+At present rust supports building under two ABIs: GNU and MSVC (comes with Visual Studio Tools). Your choice depends on the C/C++ libraries you want to interoperate with.
+
+Automated building from source isn't tested. However it should work in Cygwin or with the environmental variables as defined by `msys2_shell.cmd` or `vcvars64.bat` per the desired ABI.

layers/+tools/rustc/config.vim

@@ -0,0 +1,17 @@
+execute 'source '.fnamemodify(expand('<sfile>'), ':h').'/native-dependency.vim'
+
+if spacevim#vim#plug#LocateDependency('rust')[0] ==# 'none'
+  call spacevim#util#warn('rustc layer failure, try ":call dein#get('.
+    \ '"rust").hook_post_update()" to build as plugin, or set $RUSTC/'.
+    \ '$PATH to existing build, or install system-wide with version >= '.
+    \ join(g:spacevim#vim#plug#native_dependency['rust'].v_req, '.').'.')
+else
+  " Add cargo installed binaries to PATH, e.g. deno, tree-sitter
+  if exists('$CARGO_INSTALL_ROOT')
+    call spacevim#util#PostfixPATH(expand('$CARGO_INSTALL_ROOT/bin'))
+  elseif exists('$CARGO_HOME')
+    call spacevim#util#PostfixPATH(expand('$CARGO_HOME/bin'))
+  else
+    call spacevim#util#PostfixPATH(expand('$HOME/.cargo/bin'))
+  endif
+endif

layers/+tools/rustc/native-dependency.vim

@@ -0,0 +1,48 @@
+function! Build(native) abort
+  let python = (g:spacevim.os.windows ? 'python ' : './')
+  call system(python.a:native.plugpath.'/src/bootstrap/configure.py '.
+    \ '--prefix='.a:native.plugpath.'/install --bindir=bin --libdir=lib'.
+    \ ' --sysconfdir=. --disable-docs')
+
+  if filereadable('config.toml')
+    " profile=user setting unsupported through configure.py interface
+    execute ':tabnew +%s/\\V\#profile\ \=\ \<none\>/profile\ \=\ \"user\"/e|up config.toml'
+    call spacevim#util#info('Edit config.toml rustc configuration if desired...')
+  endif
+
+  call execute('AsyncRun -cwd='.a:native.plugpath.'/build -mode=term '.
+    \ '-pos=tab -post='.
+    \ 'call\ spacevim\#vim\#plug\#PostBuild(code,\ ''rust'') @ '.
+    \ python.'x.py build && '.python.'x.py install')
+endfunction
+
+function! PostBuild(native) abort
+  "TODO: Comment?
+  "call delete('library', 'rf')
+  "call delete('Makefile')
+  "call delete('src', 'rf')
+  " Install rg and fd tools if not on system
+  if executable('rg') != 1
+    call spacevim#vim#plug#post_update('', 'cargo install --locked ripgrep')
+  endif
+  if executable('fd') != 1
+    call spacevim#vim#plug#post_update('', 'cargo install --locked fd-find')
+  endif
+  if executable('delta') != 1
+    call spacevim#vim#plug#post_update('', 'cargo install --locked git-delta')
+  endif
+  if executable('bat') != 1
+    call spacevim#vim#plug#post_update('', 'cargo install --locked bat')
+  endif
+endfunction
+
+let g:spacevim#vim#plug#native_dependency = get(g:, 'spacevim#vim#plug#native_dependency', {})
+let g:spacevim#vim#plug#native_dependency['rust'] = {
+  \ 'bin': 'rustc',
+  \ 'override': '$RUSTC',
+  \ 'repo': 'rust-lang/rust',
+  \ 'vregex': '\Vrustc \(\[0-9]\+\).\(\[0-9]\+\).\(\[0-9]\+\)',
+  \ 'v_req': [1, 56, 0],
+  \ 'Build': function('Build'),
+  \ 'PostBuild': function('PostBuild'),
+\ }

layers/+tools/rustc/packages.vim

@@ -0,0 +1,6 @@
+execute 'source '.fnamemodify(expand('<sfile>'), ':h').'/native-dependency.vim'
+
+if spacevim#vim#plug#LocateDependency('rust')[0] ==# 'none'
+  MP 'rust-lang/rust', { 'merged': v:false, 'rtp': '',
+    \ 'hook_post_update': function('spacevim#vim#plug#Build', ['rust']) }
+endif