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+" Author: Jesse Harris - https://github.com/zigford
+" Description: This file adds support for powershell scripts synatax errors
+
+call ale#Set('powershell_powershell_executable', 'pwsh')
+
+function! ale_linters#powershell#powershell#GetExecutable(buffer) abort
+    return ale#Var(a:buffer, 'powershell_powershell_executable')
+endfunction
+
+" Some powershell magic to show syntax errors without executing the script
+" thanks to keith hill:
+" https://rkeithhill.wordpress.com/2007/10/30/powershell-quicktip-preparsing-scripts-to-check-for-syntax-errors/
+function! ale_linters#powershell#powershell#GetCommand(buffer) abort
+    let l:script = ['Param($Script);
+    \   trap {$_;continue} & {
+    \   $Contents = Get-Content -Path $Script;
+    \   $Contents = [string]::Join([Environment]::NewLine, $Contents);
+    \   [void]$ExecutionContext.InvokeCommand.NewScriptBlock($Contents);
+    \   };']
+
+    return ale#powershell#RunPowerShell(
+    \   a:buffer, 'powershell_powershell', l:script)
+endfunction
+
+" Parse powershell error output using regex into a list of dicts
+function! ale_linters#powershell#powershell#Handle(buffer, lines) abort
+    let l:output = []
+    " Our 3 patterns we need to scrape the data for the dicts
+    let l:patterns = [
+    \   '\v^At line:(\d+) char:(\d+)',
+    \   '\v^(At|\+| )@!.*',
+    \   '\vFullyQualifiedErrorId : (\w+)',
+    \]
+
+    let l:matchcount = 0
+
+    for l:match in ale#util#GetMatches(a:lines, l:patterns)
+        " We want to work with 3 matches per syntax error
+        let l:matchcount = l:matchcount + 1
+
+        if l:matchcount == 1 || str2nr(l:match[1])
+            " First match consists of 2 capture groups, and
+            " can capture the line and col
+            if exists('l:item')
+                " We may be here because the last syntax
+                " didn't emit a code, and so only had 2
+                " matches
+                call add(l:output, l:item)
+                let l:matchcount = 1
+            endif
+
+            let l:item = {
+            \   'lnum': str2nr(l:match[1]),
+            \   'col': str2nr(l:match[2]),
+            \   'type': 'E',
+            \}
+        elseif l:matchcount == 2
+            " Second match[0] grabs the full line in order
+            " to handles the text
+            let l:item['text'] = l:match[0]
+        else
+            " Final match handles the code, however
+            " powershell only emits 1 code for all errors
+            " so, we get the final code on the last error
+            " and loop over the previously added items to
+            " append the code we now know
+            call add(l:output, l:item)
+            unlet l:item
+
+            if len(l:match[1]) > 0
+                for l:i in l:output
+                    let l:i['code'] = l:match[1]
+                endfor
+            endif
+
+            " Reset the matchcount so we can begin gathering
+            " matches for the next syntax error
+            let l:matchcount = 0
+        endif
+    endfor
+
+    return l:output
+endfunction
+
+call ale#linter#Define('powershell', {
+\   'name': 'powershell',
+\   'executable_callback': 'ale_linters#powershell#powershell#GetExecutable',
+\   'command_callback': 'ale_linters#powershell#powershell#GetCommand',
+\   'output_stream': 'stdout',
+\   'callback': 'ale_linters#powershell#powershell#Handle',
+\})