Linter for powershell syntax errors (#2413)

* Linter for powershell syntax errors

2 files changed, 95 insertions, 33 deletions

diff --git a/ale_linters/powershell/powershell.vim b/ale_linters/powershell/powershell.vim
new file mode 100755
index 00000000..51ded71d
--- /dev/null
+++ b/ale_linters/powershell/powershell.vim
@@ -0,0 +1,91 @@
+" 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',
+\})
diff --git a/ale_linters/powershell/psscriptanalyzer.vim b/ale_linters/powershell/psscriptanalyzer.vim
index 8440d771..4794d9d8 100644
--- a/ale_linters/powershell/psscriptanalyzer.vim
+++ b/ale_linters/powershell/psscriptanalyzer.vim
@@ -13,37 +13,6 @@ function! ale_linters#powershell#psscriptanalyzer#GetExecutable(buffer) abort
     return ale#Var(a:buffer, 'powershell_psscriptanalyzer_executable')
 endfunction
 
-" Write a powershell script to a temp file for execution
-" return the command used to execute it
-function! s:TemporaryPSScript(buffer, input) abort
-    let l:filename = 'script.ps1'
-    " Create a temp dir to house our temp .ps1 script
-    " a temp dir is needed as powershell needs the .ps1
-    " extension
-    let l:tempdir = ale#util#Tempname() . (has('win32') ? '\' : '/')
-    let l:tempscript = l:tempdir . l:filename
-    " Create the temporary directory for the file, unreadable by 'other'
-    " users.
-    call mkdir(l:tempdir, '', 0750)
-    " Automatically delete the directory later.
-    call ale#command#ManageDirectory(a:buffer, l:tempdir)
-    " Write the script input out to a file.
-    call ale#util#Writefile(a:buffer, a:input, l:tempscript)
-
-    return l:tempscript
-endfunction
-
-function! ale_linters#powershell#psscriptanalyzer#RunPowerShell(buffer, command) abort
-    let l:executable = ale_linters#powershell#psscriptanalyzer#GetExecutable(
-    \ a:buffer)
-    let l:tempscript = s:TemporaryPSScript(a:buffer, a:command)
-
-    return ale#Escape(l:executable)
-    \ . ' -Exe Bypass -NoProfile -File '
-    \ . ale#Escape(l:tempscript)
-    \ . ' %t'
-endfunction
-
 " Run Invoke-ScriptAnalyzer and output each linting message as 4 seperate lines
 " for each parsing
 function! ale_linters#powershell#psscriptanalyzer#GetCommand(buffer) abort
@@ -60,8 +29,10 @@ function! ale_linters#powershell#psscriptanalyzer#GetCommand(buffer) abort
     \   $_.Message;
     \   $_.RuleName}']
 
-    return ale_linters#powershell#psscriptanalyzer#RunPowerShell(
-    \   a:buffer, l:script)
+    return ale#powershell#RunPowerShell(
+    \   a:buffer,
+    \   'powershell_psscriptanalyzer',
+    \   l:script)
 endfunction
 
 " add every 4 lines to an item(Dict) and every item to a list