diff --git a/runtime/autoload/rust.vim b/runtime/autoload/rust.vim
index 4230332..5ccbf4b 100644
--- a/runtime/autoload/rust.vim
+++ b/runtime/autoload/rust.vim
@@ -1,207 +1,258 @@
-" Author: Lily Ballard
 " Description: Helper functions for Rust commands/mappings
-" Last Modified: May 27, 2014
+" Last Modified: 2023-09-11
 " For bugs, patches and license go to https://github.com/rust-lang/rust.vim
 
+function! rust#Load()
+    " Utility call to get this script loaded, for debugging
+endfunction
+
+function! rust#GetConfigVar(name, default)
+    " Local buffer variable with same name takes predeence over global
+    if has_key(b:, a:name)
+        return get(b:, a:name)
+    endif
+    if has_key(g:, a:name)
+        return get(g:, a:name)
+    endif
+    return a:default
+endfunction
+
+" Include expression {{{1
+
+function! rust#IncludeExpr(fname) abort
+    " Remove leading 'crate::' to deal with 2018 edition style 'use'
+    " statements
+    let l:fname = substitute(a:fname, '^crate::', '', '')
+
+    " Remove trailing colons arising from lines like
+    "
+    "     use foo::{Bar, Baz};
+    let l:fname = substitute(l:fname, ':\+$', '', '')
+
+    " Replace '::' with '/'
+    let l:fname = substitute(l:fname, '::', '/', 'g')
+
+    " When we have
+    "
+    "    use foo::bar::baz;
+    "
+    " we can't tell whether baz is a module or a function; and we can't tell
+    " which modules correspond to files.
+    "
+    " So we work our way up, trying
+    "
+    "     foo/bar/baz.rs
+    "     foo/bar.rs
+    "     foo.rs
+    while l:fname !=# '.'
+        let l:path = findfile(l:fname)
+        if !empty(l:path)
+            return l:fname
+        endif
+        let l:fname = fnamemodify(l:fname, ':h')
+    endwhile
+    return l:fname
+endfunction
+
 " Jump {{{1
 
 function! rust#Jump(mode, function) range
-	let cnt = v:count1
-	normal! m'
-	if a:mode ==# 'v'
-		norm! gv
-	endif
-	let foldenable = &foldenable
-	set nofoldenable
-	while cnt > 0
-		execute "call <SID>Jump_" . a:function . "()"
-		let cnt = cnt - 1
-	endwhile
-	let &foldenable = foldenable
+    let cnt = v:count1
+    normal! m'
+    if a:mode ==# 'v'
+        norm! gv
+    endif
+    let foldenable = &foldenable
+    set nofoldenable
+    while cnt > 0
+        execute "call <SID>Jump_" . a:function . "()"
+        let cnt = cnt - 1
+    endwhile
+    let &foldenable = foldenable
 endfunction
 
 function! s:Jump_Back()
-	call search('{', 'b')
-	keepjumps normal! w99[{
+    call search('{', 'b')
+    keepjumps normal! w99[{
 endfunction
 
 function! s:Jump_Forward()
-	normal! j0
-	call search('{', 'b')
-	keepjumps normal! w99[{%
-	call search('{')
+    normal! j0
+    call search('{', 'b')
+    keepjumps normal! w99[{%
+    call search('{')
 endfunction
 
 " Run {{{1
 
 function! rust#Run(bang, args)
-	let args = s:ShellTokenize(a:args)
-	if a:bang
-		let idx = index(l:args, '--')
-		if idx != -1
-			let rustc_args = idx == 0 ? [] : l:args[:idx-1]
-			let args = l:args[idx+1:]
-		else
-			let rustc_args = l:args
-			let args = []
-		endif
-	else
-		let rustc_args = []
-	endif
+    let args = s:ShellTokenize(a:args)
+    if a:bang
+        let idx = index(l:args, '--')
+        if idx != -1
+            let rustc_args = idx == 0 ? [] : l:args[:idx-1]
+            let args = l:args[idx+1:]
+        else
+            let rustc_args = l:args
+            let args = []
+        endif
+    else
+        let rustc_args = []
+    endif
 
-	let b:rust_last_rustc_args = l:rustc_args
-	let b:rust_last_args = l:args
+    let b:rust_last_rustc_args = l:rustc_args
+    let b:rust_last_args = l:args
 
-	call s:WithPath(function("s:Run"), rustc_args, args)
+    call s:WithPath(function("s:Run"), rustc_args, args)
 endfunction
 
 function! s:Run(dict, rustc_args, args)
-	let exepath = a:dict.tmpdir.'/'.fnamemodify(a:dict.path, ':t:r')
-	if has('win32')
-		let exepath .= '.exe'
-	endif
+    let exepath = a:dict.tmpdir.'/'.fnamemodify(a:dict.path, ':t:r')
+    if has('win32')
+        let exepath .= '.exe'
+    endif
 
-	let relpath = get(a:dict, 'tmpdir_relpath', a:dict.path)
-	let rustc_args = [relpath, '-o', exepath] + a:rustc_args
+    let relpath = get(a:dict, 'tmpdir_relpath', a:dict.path)
+    let rustc_args = [relpath, '-o', exepath] + a:rustc_args
 
-	let rustc = exists("g:rustc_path") ? g:rustc_path : "rustc"
+    let rustc = exists("g:rustc_path") ? g:rustc_path : "rustc"
 
-	let pwd = a:dict.istemp ? a:dict.tmpdir : ''
-	let output = s:system(pwd, shellescape(rustc) . " " . join(map(rustc_args, 'shellescape(v:val)')))
-	if output != ''
-		echohl WarningMsg
-		echo output
-		echohl None
-	endif
-	if !v:shell_error
-		exe '!' . shellescape(exepath) . " " . join(map(a:args, 'shellescape(v:val)'))
-	endif
+    let pwd = a:dict.istemp ? a:dict.tmpdir : ''
+    let output = s:system(pwd, shellescape(rustc) . " " . join(map(rustc_args, 'shellescape(v:val)')))
+    if output !=# ''
+        echohl WarningMsg
+        echo output
+        echohl None
+    endif
+    if !v:shell_error
+        exe '!' . shellescape(exepath) . " " . join(map(a:args, 'shellescape(v:val)'))
+    endif
 endfunction
 
 " Expand {{{1
 
 function! rust#Expand(bang, args)
-	let args = s:ShellTokenize(a:args)
-	if a:bang && !empty(l:args)
-		let pretty = remove(l:args, 0)
-	else
-		let pretty = "expanded"
-	endif
-	call s:WithPath(function("s:Expand"), pretty, args)
+    let args = s:ShellTokenize(a:args)
+    if a:bang && !empty(l:args)
+        let pretty = remove(l:args, 0)
+    else
+        let pretty = "expanded"
+    endif
+    call s:WithPath(function("s:Expand"), pretty, args)
 endfunction
 
 function! s:Expand(dict, pretty, args)
-	try
-		let rustc = exists("g:rustc_path") ? g:rustc_path : "rustc"
+    try
+        let rustc = exists("g:rustc_path") ? g:rustc_path : "rustc"
 
-		if a:pretty =~? '^\%(everybody_loops$\|flowgraph=\)'
-			let flag = '--xpretty'
-		else
-			let flag = '--pretty'
-		endif
-		let relpath = get(a:dict, 'tmpdir_relpath', a:dict.path)
-		let args = [relpath, '-Z', 'unstable-options', l:flag, a:pretty] + a:args
-		let pwd = a:dict.istemp ? a:dict.tmpdir : ''
-		let output = s:system(pwd, shellescape(rustc) . " " . join(map(args, 'shellescape(v:val)')))
-		if v:shell_error
-			echohl WarningMsg
-			echo output
-			echohl None
-		else
-			new
-			silent put =output
-			1
-			d
-			setl filetype=rust
-			setl buftype=nofile
-			setl bufhidden=hide
-			setl noswapfile
-			" give the buffer a nice name
-			let suffix = 1
-			let basename = fnamemodify(a:dict.path, ':t:r')
-			while 1
-				let bufname = basename
-				if suffix > 1 | let bufname .= ' ('.suffix.')' | endif
-				let bufname .= '.pretty.rs'
-				if bufexists(bufname)
-					let suffix += 1
-					continue
-				endif
-				exe 'silent noautocmd keepalt file' fnameescape(bufname)
-				break
-			endwhile
-		endif
-	endtry
+        if a:pretty =~? '^\%(everybody_loops$\|flowgraph=\)'
+            let flag = '--xpretty'
+        else
+            let flag = '--pretty'
+        endif
+        let relpath = get(a:dict, 'tmpdir_relpath', a:dict.path)
+        let args = [relpath, '-Z', 'unstable-options', l:flag, a:pretty] + a:args
+        let pwd = a:dict.istemp ? a:dict.tmpdir : ''
+        let output = s:system(pwd, shellescape(rustc) . " " . join(map(args, 'shellescape(v:val)')))
+        if v:shell_error
+            echohl WarningMsg
+            echo output
+            echohl None
+        else
+            new
+            silent put =output
+            1
+            d
+            setl filetype=rust
+            setl buftype=nofile
+            setl bufhidden=hide
+            setl noswapfile
+            " give the buffer a nice name
+            let suffix = 1
+            let basename = fnamemodify(a:dict.path, ':t:r')
+            while 1
+                let bufname = basename
+                if suffix > 1 | let bufname .= ' ('.suffix.')' | endif
+                let bufname .= '.pretty.rs'
+                if bufexists(bufname)
+                    let suffix += 1
+                    continue
+                endif
+                exe 'silent noautocmd keepalt file' fnameescape(bufname)
+                break
+            endwhile
+        endif
+    endtry
 endfunction
 
 function! rust#CompleteExpand(lead, line, pos)
-	if a:line[: a:pos-1] =~ '^RustExpand!\s*\S*$'
-		" first argument and it has a !
-		let list = ["normal", "expanded", "typed", "expanded,identified", "flowgraph=", "everybody_loops"]
-		if !empty(a:lead)
-			call filter(list, "v:val[:len(a:lead)-1] == a:lead")
-		endif
-		return list
-	endif
+    if a:line[: a:pos-1] =~# '^RustExpand!\s*\S*$'
+        " first argument and it has a !
+        let list = ["normal", "expanded", "typed", "expanded,identified", "flowgraph=", "everybody_loops"]
+        if !empty(a:lead)
+            call filter(list, "v:val[:len(a:lead)-1] == a:lead")
+        endif
+        return list
+    endif
 
-	return glob(escape(a:lead, "*?[") . '*', 0, 1)
+    return glob(escape(a:lead, "*?[") . '*', 0, 1)
 endfunction
 
 " Emit {{{1
 
 function! rust#Emit(type, args)
-	let args = s:ShellTokenize(a:args)
-	call s:WithPath(function("s:Emit"), a:type, args)
+    let args = s:ShellTokenize(a:args)
+    call s:WithPath(function("s:Emit"), a:type, args)
 endfunction
 
 function! s:Emit(dict, type, args)
-	try
-		let output_path = a:dict.tmpdir.'/output'
+    try
+        let output_path = a:dict.tmpdir.'/output'
 
-		let rustc = exists("g:rustc_path") ? g:rustc_path : "rustc"
+        let rustc = exists("g:rustc_path") ? g:rustc_path : "rustc"
 
-		let relpath = get(a:dict, 'tmpdir_relpath', a:dict.path)
-		let args = [relpath, '--emit', a:type, '-o', output_path] + a:args
-		let pwd = a:dict.istemp ? a:dict.tmpdir : ''
-		let output = s:system(pwd, shellescape(rustc) . " " . join(map(args, 'shellescape(v:val)')))
-		if output != ''
-			echohl WarningMsg
-			echo output
-			echohl None
-		endif
-		if !v:shell_error
-			new
-			exe 'silent keepalt read' fnameescape(output_path)
-			1
-			d
-			if a:type == "llvm-ir"
-				setl filetype=llvm
-				let extension = 'll'
-			elseif a:type == "asm"
-				setl filetype=asm
-				let extension = 's'
-			endif
-			setl buftype=nofile
-			setl bufhidden=hide
-			setl noswapfile
-			if exists('l:extension')
-				" give the buffer a nice name
-				let suffix = 1
-				let basename = fnamemodify(a:dict.path, ':t:r')
-				while 1
-					let bufname = basename
-					if suffix > 1 | let bufname .= ' ('.suffix.')' | endif
-					let bufname .= '.'.extension
-					if bufexists(bufname)
-						let suffix += 1
-						continue
-					endif
-					exe 'silent noautocmd keepalt file' fnameescape(bufname)
-					break
-				endwhile
-			endif
-		endif
-	endtry
+        let relpath = get(a:dict, 'tmpdir_relpath', a:dict.path)
+        let args = [relpath, '--emit', a:type, '-o', output_path] + a:args
+        let pwd = a:dict.istemp ? a:dict.tmpdir : ''
+        let output = s:system(pwd, shellescape(rustc) . " " . join(map(args, 'shellescape(v:val)')))
+        if output !=# ''
+            echohl WarningMsg
+            echo output
+            echohl None
+        endif
+        if !v:shell_error
+            new
+            exe 'silent keepalt read' fnameescape(output_path)
+            1
+            d
+            if a:type ==# "llvm-ir"
+                setl filetype=llvm
+                let extension = 'll'
+            elseif a:type ==# "asm"
+                setl filetype=asm
+                let extension = 's'
+            endif
+            setl buftype=nofile
+            setl bufhidden=hide
+            setl noswapfile
+            if exists('l:extension')
+                " give the buffer a nice name
+                let suffix = 1
+                let basename = fnamemodify(a:dict.path, ':t:r')
+                while 1
+                    let bufname = basename
+                    if suffix > 1 | let bufname .= ' ('.suffix.')' | endif
+                    let bufname .= '.'.extension
+                    if bufexists(bufname)
+                        let suffix += 1
+                        continue
+                    endif
+                    exe 'silent noautocmd keepalt file' fnameescape(bufname)
+                    break
+                endwhile
+            endif
+        endif
+    endtry
 endfunction
 
 " Utility functions {{{1
@@ -219,145 +270,154 @@
 " existing path of the current buffer. If the path is inside of {dict.tmpdir}
 " then it is guaranteed to have a '.rs' extension.
 function! s:WithPath(func, ...)
-	let buf = bufnr('')
-	let saved = {}
-	let dict = {}
-	try
-		let saved.write = &write
-		set write
-		let dict.path = expand('%')
-		let pathisempty = empty(dict.path)
+    let buf = bufnr('')
+    let saved = {}
+    let dict = {}
+    try
+        let saved.write = &write
+        set write
+        let dict.path = expand('%')
+        let pathisempty = empty(dict.path)
 
-		" Always create a tmpdir in case the wrapped command wants it
-		let dict.tmpdir = tempname()
-		call mkdir(dict.tmpdir)
+        " Always create a tmpdir in case the wrapped command wants it
+        let dict.tmpdir = tempname()
+        call mkdir(dict.tmpdir)
 
-		if pathisempty || !saved.write
-			let dict.istemp = 1
-			" if we're doing this because of nowrite, preserve the filename
-			if !pathisempty
-				let filename = expand('%:t:r').".rs"
-			else
-				let filename = 'unnamed.rs'
-			endif
-			let dict.tmpdir_relpath = filename
-			let dict.path = dict.tmpdir.'/'.filename
+        if pathisempty || !saved.write
+            let dict.istemp = 1
+            " if we're doing this because of nowrite, preserve the filename
+            if !pathisempty
+                let filename = expand('%:t:r').".rs"
+            else
+                let filename = 'unnamed.rs'
+            endif
+            let dict.tmpdir_relpath = filename
+            let dict.path = dict.tmpdir.'/'.filename
 
-			let saved.mod = &mod
-			set nomod
+            let saved.mod = &modified
+            set nomodified
 
-			silent exe 'keepalt write! ' . fnameescape(dict.path)
-			if pathisempty
-				silent keepalt 0file
-			endif
-		else
-			let dict.istemp = 0
-			update
-		endif
+            silent exe 'keepalt write! ' . fnameescape(dict.path)
+            if pathisempty
+                silent keepalt 0file
+            endif
+        else
+            let dict.istemp = 0
+            update
+        endif
 
-		call call(a:func, [dict] + a:000)
-	finally
-		if bufexists(buf)
-			for [opt, value] in items(saved)
-				silent call setbufvar(buf, '&'.opt, value)
-				unlet value " avoid variable type mismatches
-			endfor
-		endif
-		if has_key(dict, 'tmpdir') | silent call s:RmDir(dict.tmpdir) | endif
-	endtry
+        call call(a:func, [dict] + a:000)
+    finally
+        if bufexists(buf)
+            for [opt, value] in items(saved)
+                silent call setbufvar(buf, '&'.opt, value)
+                unlet value " avoid variable type mismatches
+            endfor
+        endif
+        if has_key(dict, 'tmpdir') | silent call s:RmDir(dict.tmpdir) | endif
+    endtry
 endfunction
 
 function! rust#AppendCmdLine(text)
-	call setcmdpos(getcmdpos())
-	let cmd = getcmdline() . a:text
-	return cmd
+    call setcmdpos(getcmdpos())
+    let cmd = getcmdline() . a:text
+    return cmd
 endfunction
 
 " Tokenize the string according to sh parsing rules
 function! s:ShellTokenize(text)
-	" states:
-	" 0: start of word
-	" 1: unquoted
-	" 2: unquoted backslash
-	" 3: double-quote
-	" 4: double-quoted backslash
-	" 5: single-quote
-	let l:state = 0
-	let l:current = ''
-	let l:args = []
-	for c in split(a:text, '\zs')
-		if l:state == 0 || l:state == 1 " unquoted
-			if l:c ==# ' '
-				if l:state == 0 | continue | endif
-				call add(l:args, l:current)
-				let l:current = ''
-				let l:state = 0
-			elseif l:c ==# '\'
-				let l:state = 2
-			elseif l:c ==# '"'
-				let l:state = 3
-			elseif l:c ==# "'"
-				let l:state = 5
-			else
-				let l:current .= l:c
-				let l:state = 1
-			endif
-		elseif l:state == 2 " unquoted backslash
-			if l:c !=# "\n" " can it even be \n?
-				let l:current .= l:c
-			endif
-			let l:state = 1
-		elseif l:state == 3 " double-quote
-			if l:c ==# '\'
-				let l:state = 4
-			elseif l:c ==# '"'
-				let l:state = 1
-			else
-				let l:current .= l:c
-			endif
-		elseif l:state == 4 " double-quoted backslash
-			if stridx('$`"\', l:c) >= 0
-				let l:current .= l:c
-			elseif l:c ==# "\n" " is this even possible?
-				" skip it
-			else
-				let l:current .= '\'.l:c
-			endif
-			let l:state = 3
-		elseif l:state == 5 " single-quoted
-			if l:c == "'"
-				let l:state = 1
-			else
-				let l:current .= l:c
-			endif
-		endif
-	endfor
-	if l:state != 0
-		call add(l:args, l:current)
-	endif
-	return l:args
+    " states:
+    " 0: start of word
+    " 1: unquoted
+    " 2: unquoted backslash
+    " 3: double-quote
+    " 4: double-quoted backslash
+    " 5: single-quote
+    let l:state = 0
+    let l:current = ''
+    let l:args = []
+    for c in split(a:text, '\zs')
+        if l:state == 0 || l:state == 1 " unquoted
+            if l:c ==# ' '
+                if l:state == 0 | continue | endif
+                call add(l:args, l:current)
+                let l:current = ''
+                let l:state = 0
+            elseif l:c ==# '\'
+                let l:state = 2
+            elseif l:c ==# '"'
+                let l:state = 3
+            elseif l:c ==# "'"
+                let l:state = 5
+            else
+                let l:current .= l:c
+                let l:state = 1
+            endif
+        elseif l:state == 2 " unquoted backslash
+            if l:c !=# "\n" " can it even be \n?
+                let l:current .= l:c
+            endif
+            let l:state = 1
+        elseif l:state == 3 " double-quote
+            if l:c ==# '\'
+                let l:state = 4
+            elseif l:c ==# '"'
+                let l:state = 1
+            else
+                let l:current .= l:c
+            endif
+        elseif l:state == 4 " double-quoted backslash
+            if stridx('$`"\', l:c) >= 0
+                let l:current .= l:c
+            elseif l:c ==# "\n" " is this even possible?
+                " skip it
+            else
+                let l:current .= '\'.l:c
+            endif
+            let l:state = 3
+        elseif l:state == 5 " single-quoted
+            if l:c ==# "'"
+                let l:state = 1
+            else
+                let l:current .= l:c
+            endif
+        endif
+    endfor
+    if l:state != 0
+        call add(l:args, l:current)
+    endif
+    return l:args
 endfunction
 
 function! s:RmDir(path)
-	" sanity check; make sure it's not empty, /, or $HOME
-	if empty(a:path)
-		echoerr 'Attempted to delete empty path'
-		return 0
-	elseif a:path == '/' || a:path == $HOME
-		echoerr 'Attempted to delete protected path: ' . a:path
-		return 0
-	endif
-	return system("rm -rf " . shellescape(a:path))
+    " sanity check; make sure it's not empty, /, or $HOME
+    if empty(a:path)
+        echoerr 'Attempted to delete empty path'
+        return 0
+    elseif a:path ==# '/' || a:path ==# $HOME
+        let l:path = expand(a:path)
+        if l:path ==# '/' || l:path ==# $HOME
+            echoerr 'Attempted to delete protected path: ' . a:path
+            return 0
+        endif
+    endif
+
+    if !isdirectory(a:path)
+        return 0
+    endif
+
+    " delete() returns 0 when removing file successfully
+    return delete(a:path, 'rf') == 0
 endfunction
 
 " Executes {cmd} with the cwd set to {pwd}, without changing Vim's cwd.
 " If {pwd} is the empty string then it doesn't change the cwd.
 function! s:system(pwd, cmd)
-	let cmd = a:cmd
-	if !empty(a:pwd)
-		let cmd = 'cd ' . shellescape(a:pwd) . ' && ' . cmd
-	endif
-	return system(cmd)
+    let cmd = a:cmd
+    if !empty(a:pwd)
+        let cmd = 'cd ' . shellescape(a:pwd) . ' && ' . cmd
+    endif
+    return system(cmd)
 endfunction
 
 " Playpen Support {{{1
@@ -366,10 +426,10 @@
 " http://github.com/mattn/gist-vim
 function! s:has_webapi()
     if !exists("*webapi#http#post")
-	try
-	    call webapi#http#post()
-	catch
-	endtry
+        try
+            call webapi#http#post()
+        catch
+        endtry
     endif
     return exists("*webapi#http#post")
 endfunction
@@ -381,35 +441,130 @@
     let l:rust_shortener_url = get(g:, 'rust_shortener_url', 'https://is.gd/')
 
     if !s:has_webapi()
-	echohl ErrorMsg | echomsg ':RustPlay depends on webapi.vim (https://github.com/mattn/webapi-vim)' | echohl None
-	return
+        echohl ErrorMsg | echomsg ':RustPlay depends on webapi.vim (https://github.com/mattn/webapi-vim)' | echohl None
+        return
     endif
 
     let bufname = bufname('%')
     if a:count < 1
-	let content = join(getline(a:line1, a:line2), "\n")
+        let content = join(getline(a:line1, a:line2), "\n")
     else
-	let save_regcont = @"
-	let save_regtype = getregtype('"')
-	silent! normal! gvy
-	let content = @"
-	call setreg('"', save_regcont, save_regtype)
+        let save_regcont = @"
+        let save_regtype = getregtype('"')
+        silent! normal! gvy
+        let content = @"
+        call setreg('"', save_regcont, save_regtype)
     endif
 
-    let body = l:rust_playpen_url."?code=".webapi#http#encodeURI(content)
+    let url = l:rust_playpen_url."?code=".webapi#http#encodeURI(content)
 
-    if strlen(body) > 5000
-	echohl ErrorMsg | echomsg 'Buffer too large, max 5000 encoded characters ('.strlen(body).')' | echohl None
-	return
+    if strlen(url) > 5000
+        echohl ErrorMsg | echomsg 'Buffer too large, max 5000 encoded characters ('.strlen(url).')' | echohl None
+        return
     endif
 
-    let payload = "format=simple&url=".webapi#http#encodeURI(body)
+    let payload = "format=simple&url=".webapi#http#encodeURI(url)
     let res = webapi#http#post(l:rust_shortener_url.'create.php', payload, {})
-    let url = res.content
+    if res.status[0] ==# '2'
+        let url = res.content
+    endif
 
-    redraw | echomsg 'Done: '.url
+    let footer = ''
+    if exists('g:rust_clip_command')
+        call system(g:rust_clip_command, url)
+        if !v:shell_error
+            let footer = ' (copied to clipboard)'
+        endif
+    endif
+    redraw | echomsg 'Done: '.url.footer
+endfunction
+
+" Run a test under the cursor or all tests {{{1
+
+" Finds a test function name under the cursor. Returns empty string when a
+" test function is not found.
+function! s:SearchTestFunctionNameUnderCursor() abort
+    let cursor_line = line('.')
+
+    " Find #[test] attribute
+    if search('\m\C#\[test\]', 'bcW') is 0
+        return ''
+    endif
+
+    " Move to an opening brace of the test function
+    let test_func_line = search('\m\C^\s*fn\s\+\h\w*\s*(.\+{$', 'eW')
+    if test_func_line is 0
+        return ''
+    endif
+
+    " Search the end of test function (closing brace) to ensure that the
+    " cursor position is within function definition
+    if maparg('<Plug>(MatchitNormalForward)') ==# ''
+        keepjumps normal! %
+    else
+        " Prefer matchit.vim official plugin to native % since the plugin
+        " provides better behavior than original % (#391)
+        " To load the plugin, run:
+        "   :packadd matchit
+        execute 'keepjumps' 'normal' "\<Plug>(MatchitNormalForward)"
+    endif
+    if line('.') < cursor_line
+        return ''
+    endif
+
+    return matchstr(getline(test_func_line), '\m\C^\s*fn\s\+\zs\h\w*')
+endfunction
+
+function! rust#Test(mods, winsize, all, options) abort
+    let manifest = findfile('Cargo.toml', expand('%:p:h') . ';')
+    if manifest ==# ''
+        return rust#Run(1, '--test ' . a:options)
+    endif
+
+    " <count> defaults to 0, but we prefer an empty string
+    let winsize = a:winsize ? a:winsize : ''
+
+    if has('terminal')
+        if has('patch-8.0.910')
+            let cmd = printf('%s noautocmd %snew | terminal ++curwin ', a:mods, winsize)
+        else
+            let cmd = printf('%s terminal ', a:mods)
+        endif
+    elseif has('nvim')
+        let cmd = printf('%s noautocmd %snew | terminal ', a:mods, winsize)
+    else
+        let cmd = '!'
+        let manifest = shellescape(manifest)
+    endif
+
+    if a:all
+        if a:options ==# ''
+            execute cmd . 'cargo test --manifest-path' manifest
+        else
+            execute cmd . 'cargo test --manifest-path' manifest a:options
+        endif
+        return
+    endif
+
+    let saved = getpos('.')
+    try
+        let func_name = s:SearchTestFunctionNameUnderCursor()
+    finally
+        call setpos('.', saved)
+    endtry
+    if func_name ==# ''
+        echohl ErrorMsg
+        echomsg 'No test function was found under the cursor. Please add ! to command if you want to run all tests'
+        echohl None
+        return
+    endif
+    if a:options ==# ''
+        execute cmd . 'cargo test --manifest-path' manifest func_name
+    else
+        execute cmd . 'cargo test --manifest-path' manifest func_name a:options
+    endif
 endfunction
 
 " }}}1
 
-" vim: set noet sw=8 ts=8:
+" vim: set et sw=4 sts=4 ts=8: