Implemented review recommendations

Implements suggestions and recommendations suggested by the first review
of the "Advance C# linter based on mcs -t:module (#952)" pull request.

- Clarifies and simplifies description of linters and options
- Added links to help file and marked the mcsc linter as to be run only
  when file in buffer is saved or loaded.
- Added comments to the mcsc.vim file to clarify code
- removed type checks considered not necessary be reviewer.
- addresses findings by vader
- removed call to getcwd and cd in vim script
- handler expands file names relative to route of source tree into
  absolute pathes. Fixes errors not being marked when vim is started
  from subdirectory of source tree.
- implements tests for mcs.vim and mcsc.vim linter

8 files changed, 352 insertions, 89 deletions

diff --git a/README.md b/README.md
index 9186252e..37e04c0e 100644
--- a/README.md
+++ b/README.md
@@ -76,7 +76,7 @@ formatting.
 | C | [cppcheck](http://cppcheck.sourceforge.net), [cpplint](https://github.com/google/styleguide/tree/gh-pages/cpplint), [gcc](https://gcc.gnu.org/), [clang](http://clang.llvm.org/), [clangtidy](http://clang.llvm.org/extra/clang-tidy/) !!, [clang-format](https://clang.llvm.org/docs/ClangFormat.html)|
 | C++ (filetype cpp) | [clang](http://clang.llvm.org/), [clangcheck](http://clang.llvm.org/docs/ClangCheck.html) !!, [clangtidy](http://clang.llvm.org/extra/clang-tidy/) !!, [cppcheck](http://cppcheck.sourceforge.net), [cpplint](https://github.com/google/styleguide/tree/gh-pages/cpplint) !!, [gcc](https://gcc.gnu.org/), [clang-format](https://clang.llvm.org/docs/ClangFormat.html)|
 | CUDA | [nvcc](http://docs.nvidia.com/cuda/cuda-compiler-driver-nvcc/index.html) |
-| C# | [mcs](http://www.mono-project.com/docs/about-mono/languages/csharp/) see:`help ale-cs-mcs` for details,[mcsc](http://www.mono-project.com/docs/about-mono/languages/csharp/) see:`help ale-cs-mcsc` for details and configuration|
+| C# | [mcs](http://www.mono-project.com/docs/about-mono/languages/csharp/) see:`help ale-cs-mcs` for details, [mcsc](http://www.mono-project.com/docs/about-mono/languages/csharp/) !! see:`help ale-cs-mcsc` for details and configuration|
 | Chef | [foodcritic](http://www.foodcritic.io/) |
 | CMake | [cmakelint](https://github.com/richq/cmake-lint) |
 | CoffeeScript | [coffee](http://coffeescript.org/), [coffeelint](https://www.npmjs.com/package/coffeelint) |
diff --git a/ale_linters/cs/mcsc.vim b/ale_linters/cs/mcsc.vim
index 70dc4ab6..38a08556 100644
--- a/ale_linters/cs/mcsc.vim
+++ b/ale_linters/cs/mcsc.vim
@@ -1,71 +1,72 @@
+" general mcs options which are likely to stay constant across
+" source trees like -pkg:dotnet
 let g:ale_cs_mcsc_options = get(g:, 'ale_cs_mcsc_options', '')
-let g:ale_cs_mcsc_source = get(g:,'ale_cs_mcsc_source','')
-let g:ale_cs_mcsc_assembly_path = get(g:,'ale_cs_mcsc_assembly_path',[])
-let g:ale_cs_mcsc_assemblies = get(g:,'ale_cs_mcsc_assemblies',[])
+
+" path string pointing the linter to the base path of the
+" source tree to check
+let g:ale_cs_mcsc_source = get(g:, 'ale_cs_mcsc_source','.')
+
+" list of search paths for additional assemblies to consider
+let g:ale_cs_mcsc_assembly_path = get(g:, 'ale_cs_mcsc_assembly_path',[])
+
+" list of assemblies to consider
+let g:ale_cs_mcsc_assemblies = get(g:, 'ale_cs_mcsc_assemblies',[])
 function! ale_linters#cs#mcsc#GetCommand(buffer) abort
-	let l:path = ale#Var(a:buffer,'cs_mcsc_assembly_path')
-	if !empty(l:path)
-        if type(l:path) == type('')
-            let l:path = '-lib:' . l:path
-        elseif type(l:path) == type([])
-            let l:path = '-lib:' . join(l:path,',')
-        else
-            throw 'assembly path list must be string or list of path strings'
-        endif
-    elseif type(l:path) != type('') 
-        if type(l:path) != type([])
-            throw 'assembly path list must be string or list of path strings'
-        endif
+
+    " if list of assembly search paths is not empty convert it to
+    " appropriate -lib: parameter of mcs
+    let l:path = ale#Var(a:buffer, 'cs_mcsc_assembly_path')
+
+    if !empty(l:path)
+         let l:path = '-lib:"' . join(l:path, '","') .'"'
+    else
         let l:path =''
     endif
-    let l:assemblies = ale#Var(a:buffer,'cs_mcsc_assemblies')
-	if !empty(l:assemblies)
-        if type(l:assemblies) == type('')
-            let l:assemblies = '-r' . l:assemblies
-        elseif type(l:assemblies) == type([])
-            let l:assemblies = '-r:' . join(l:assemblies,',')
-        else
-            throw 'assembly list must be string or list of strings'
-        endif
-    elseif type(l:assemblies) != type('') 
-        if type(l:assemblies) != type([])
-            throw 'assembly list must be string or list of string'
-        endif
+
+    " if list of assemblies to link is not empty convert it to the
+    " appropriate -r: parameter of mcs
+    let l:assemblies = ale#Var(a:buffer, 'cs_mcsc_assemblies')
+
+    if !empty(l:assemblies)
+        let l:assemblies = '-r:"' . join(l:assemblies, '","') . '"'
+    else
         let l:assemblies =''
     endif
-	let l:base = ale#Var(a:buffer,'cs_mcsc_source')
-	let l:cwd = getcwd()
-	if isdirectory(l:base)
-		exe 'cd ' . l:base
-	elseif empty(l:base) && ( type(l:base) == type('') )
-		let l:base = '.'
-	else
-		throw 'ale_cs_mcs_source must point to an existing directory or empty string for current'
-	endif
-	let l:out = tempname()
-	call ale#engine#ManageFile(a:buffer,l:out)
-    let l:cmd = 'cd ' . l:base . ';'
-    \    . 'mcs -unsafe' 
+
+    " register temporary module target file with ale
+    let l:out = tempname()
+    call ale#engine#ManageFile(a:buffer, l:out)
+
+    " assemble linter command string to be executed by ale
+    " implicitly set -unsafe mcs flag set compilation
+    " target to module (-t:module), direct mcs output to
+    " temporary file (-out)
+    "
+    return 'cd "' . ale#Var(a:buffer, 'cs_mcsc_source') . '";'
+    \    . 'mcs -unsafe'
     \    . ' ' . ale#Var(a:buffer, 'cs_mcsc_options')
     \    . ' ' . l:path
     \    . ' ' . l:assemblies
-	\    . ' -out:' . l:out
+    \    . ' -out:' . l:out
     \    . ' -t:module'
-    \    . ' "' . join(glob('**/*.cs',v:false,v:true),'" "') . '"'
-	exe 'cd ' . l:cwd
-	return l:cmd
+    \    . ' -recurse:"*.cs"'
 endfunction
 
 function! ale_linters#cs#mcsc#Handle(buffer, lines) abort
     " Look for lines like the following.
     "
     " Tests.cs(12,29): error CSXXXX: ; expected
+    "
+    " NOTE: pattern also captures file name as linter compiles all
+    " files within the source tree rooted at the specified source
+    " path and not just the file loaded in the buffer
     let l:pattern = '^\(.\+\.cs\)(\(\d\+\),\(\d\+\)): \(.\+\): \(.\+\)'
     let l:output = []
+    let l:source = ale#Var(a:buffer, 'cs_mcsc_source')
 
     for l:match in ale#util#GetMatches(a:lines, l:pattern)
         call add(l:output, {
-		\   'filename': l:match[1],
+        \   'filename': fnamemodify(l:source . '/' . l:match[1], ':p'),
         \   'lnum': l:match[2] + 0,
         \   'col': l:match[3] + 0,
         \   'text': l:match[4] . ': ' . l:match[5],
@@ -82,5 +83,5 @@ call ale#linter#Define('cs',{
 \   'executable': 'mcs',
 \   'command_callback': 'ale_linters#cs#mcsc#GetCommand',
 \   'callback': 'ale_linters#cs#mcsc#Handle',
-\	'lint_file': 1
+\   'lint_file': 1
 \})
diff --git a/doc/ale-cs.txt b/doc/ale-cs.txt
index 357d7387..eeb1abd1 100644
--- a/doc/ale-cs.txt
+++ b/doc/ale-cs.txt
@@ -3,10 +3,11 @@ ALE C# Integration                                             *ale-cs-options*
 
 
 ===============================================================================
-mcs                 																		           *ale-cs-mcs*
+mcs                                                                *ale-cs-mcs*
 
-  The mcs linter calls the mono mcs compiler setting the --parse and -unsafe
-  flags.
+  The mcs linter checks the syntax of the '*.cs' file loaded in the current
+  buffer only. It uses the --parse option of the mcs compiler and implicitly 
+  sets the -unsafe flag.
 
 g:ale_cs_mcs_options                                     *g:ale_cs_mcs_options*
                                                          *b:ale_cs_mcs_options*
@@ -14,62 +15,88 @@ g:ale_cs_mcs_options                                     *g:ale_cs_mcs_options*
   Type: String
   Default: `''`
 
-  This variable can be changed to modify flags given to mcs. The options
-  --parse and -unsafe are implicitly set.
+  This variable can be changed to pass additional flags given to mcs.
+
+  NOTE: The -unsafe flag is selected implicitly and thus does not need to be 
+  explicitly included in the |g:ale_cs_mcs_options| or |b:ale_cs_mcs_options|
+  parameter.
 
 
 ===============================================================================
 mcsc                                                              *ale-cs-mcsc*
 
-	The mcsc linter uses the mono mcs compiler to generate a temporary module
-  target file (-t:module) including all '*.cs' files contained in the
-	directory by specified by |g:ale_cs_mcsc_source| or |b:ale_cs_mcsc_source|
-  variable and all sub directories. Currently none can be excluded from
-  linting. It uses the assembly directories as specified by 
-	|g:ale_cs_mcsc_assembly_path| or |b:ale_cs_mcsc_assembly_path| and selects
-  the assembly files specified by |g:ale_cs_mcsc_assemblies| or 
-  |b:ale_cs_mcsc_assemblies|. The mcs -unsafe option is set implicitly and has
-  not to be added using |g:ale_cs_mcsc_options| or |b:ale_cs_mcsc_options|
-  variable.
-
-g:ale_cs_mcsc_options                                 *g:ale_cs_mcsc_options*
-                                                      *b:ale_cs_mcsc_options*
+  The mcsc linter uses the mono mcs compiler to generate a temporary module
+  target file (-t:module). The module includes including all '*.cs' files
+  contained in the directory tree rooted at the path defined by the 
+  |g:ale_cs_mcsc_source| or |b:ale_cs_mcsc_source| variable.
+  variable and all sub directories. 
+
+  The paths to search for additional assembly ('*.dll') files can be
+  specified using the |g:ale_cs_mcsc_assembly_path| or 
+  |b:ale_cs_mcsc_assembly_path| variable. The additional assembly files ('*.dll')
+  can be included through the |g:ale_cs_mcsc_assemblies| or 
+  |b:ale_cs_mcsc_assemblies| parameter. 
+
+  NOTE: mcs compiles sources in multiple phases. It stops compilation after
+  finding errors during the current phase.
+  For example assume a file named 'FileWithTypeError.cs' is edited and saved
+  which contains a Type error. In the same directory tree a file named
+  'FileWithSyntaxError.cs' exists which contains a syntax error 
+  (eg.: a missing '{'). 
+  In that case mcs and thus mcsc linter will stop after the syntax check phase is
+  finished and report the syntax error in the file 'FileWithSyntaxError.cs'. The
+  Type error in the file 'FileWithTypeError.cs is not seen jet.
+  The only possibility to find the error in in 'FileWithTypeError.cs' is to fix
+  the syntax error in 'FileWithSyntaxError.cs' first. After saving mcs will
+  successfully pass the syntax check phase and advance to the next compilation
+  phase at which the Type error hidden in 'FileWithTypeError.cs' is found  and 
+  now can be indicated  by ale.
+
+g:ale_cs_mcsc_options                                   *g:ale_cs_mcsc_options*
+                                                        *b:ale_cs_mcsc_options*
   Type: |String|
   Default: `''`
 
-  This variable can be set to set further options for example adding packages 
-  (eg.: -pkg:dotnet) with are not added per default.
+  This parameter can be used to define additional flags and parameters independent
+  of the source tree to be linted. The specified string is directly passed to
+  mcs compiler without any further change.
+
+  For example, to add the dotnet package which is not added per default
+
+      let g:ale_cs_mcs_options = '-pkg:dotnet'
 
-g:ale_cs_mcsc_source                                   *g:ale_cs_mcsc_source*
-                                                       *b:ale_cs_mcsc_source*
+  NOTE: The mcs -unsafe option is included implicitly per default. Therefore it
+  is not necessary to specify it explicitly through the |g:ale_cs_mcsc_options|
+  or |b:ale_cs_mcsc_options| parameter.
+
+g:ale_cs_mcsc_source                                     *g:ale_cs_mcsc_source*
+                                                         *b:ale_cs_mcsc_source*
   Type: |String|
   Default: `''`
 
-  This variable defines the base path of the directory tree the '*.cs' files
-  should be included into the compilation of the temporary module. If empty
-  the current directory is used.
+  This variable defines the root path of the directory tree searched for the
+  '*.cs' files to be linted. If empty the current working directory is used.
+
+  NOTE: Currently it is not possible to specify sub directories and
+  directory sub trees which shall not be searched for *.cs files.
 
-g:ale_cs_mcsc_assembly_path                     *g:ale_cs_mcsc_assembly_path*
-                                                *b:ale_cs_mcsc_assembly_path*
+g:ale_cs_mcsc_assembly_path                       *g:ale_cs_mcsc_assembly_path*
+                                                  *b:ale_cs_mcsc_assembly_path*
   Type: |List|
   Default: `[]`
 
-  This variable defines a list of absolute or relative path strings pointing
-  to the location of the assembly files (*.dll) to be considered by mcsc
-  linter. If the list is not empty the list will be added to the mcsc command
-  line using the -lib: flag of mcs.
+  This variable defines a list of path strings to be searched for external
+  assembly ('*.dll') files. The list is passed to the mcs compiler using the
+  '-lib:' flag. 
 
-g:ale_cs_mcsc_assemblies                            *g:ale_cs_mcsc_assemblies*
-                                                   *b:ale_cs_mcsc_assemblies*
+g:ale_cs_mcsc_assemblies                             *g:ale_cs_mcsc_assemblies*
+                                                     *b:ale_cs_mcsc_assemblies*
   Type: |List|
   Default: `[]`
 
-  This variable defines a list of assembly files (*.dll) to be considered by
-  the mono mcs compiler when generating the temporary module. If the list is
-  not empty the list of assemblies will be added to the mcsc command
-  line using the -r: flag of mcs. To change the search path mcs uses to 
-  locate the specified assembly files use |g:ale_cs_mcsc_assembly_path| or
-  |b:ale_cs_mcsc_assembly_path| variables
+  This variable defines a list of external assembly (*.dll) files required 
+  by the mono mcs compiler to generate a valid module target. The list is 
+  passed the mcs compiler using the '-r:' flag.
 
 ===============================================================================
   vim:tw=78:ts=2:sts=2:sw=2:ft=help:norl:
diff --git a/doc/ale.txt b/doc/ale.txt
index 32ef0a6d..fae91009 100644
--- a/doc/ale.txt
+++ b/doc/ale.txt
@@ -36,6 +36,9 @@ CONTENTS                                                         *ale-contents*
       cppcheck............................|ale-cpp-cppcheck|
       cpplint.............................|ale-cpp-cpplint|
       gcc.................................|ale-cpp-gcc|
+    c#....................................|ale-cs-options|
+      mcs.................................|ale-cs-mcs|
+      mcsc................................|ale-cs-mcsc|
     css...................................|ale-css-options|
       prettier............................|ale-css-prettier|
       stylelint...........................|ale-css-stylelint|
@@ -222,7 +225,7 @@ Notes:
 * C: `cppcheck`, `cpplint`!!, `gcc`, `clang`, `clangtidy`!!, `clang-format`
 * C++ (filetype cpp): `clang`, `clangcheck`!!, `clangtidy`!!, `cppcheck`, `cpplint`!!, `gcc`, `clang-format`
 * CUDA: `nvcc`!!
-* C#: `mcs`
+* C#: `mcs`, `mcsc`!!
 * Chef: `foodcritic`
 * CMake: `cmakelint`
 * CoffeeScript: `coffee`, `coffeelint`
diff --git a/test/command_callback/test_cs_mcs_command_callbacks.vader b/test/command_callback/test_cs_mcs_command_callbacks.vader
new file mode 100644
index 00000000..30f067ea
--- /dev/null
+++ b/test/command_callback/test_cs_mcs_command_callbacks.vader
@@ -0,0 +1,34 @@
+Before:
+  Save g:ale_cs_mcs_options
+
+  unlet! g:ale_cs_mcs_options
+
+  runtime ale_linters/cs/mcs.vim
+
+  let b:command_tail = ' -unsafe --parse'
+
+After:
+  Restore
+  unlet! b:command_tail
+  unlet! b:ale_cs_mcs_options
+  call ale#linter#Reset()
+
+Execute(Check for proper default command):
+
+  let b:command = ale_linters#cs#mcs#GetCommand(bufnr(''))
+  let b:command = substitute(b:command,'\s\+',' ','g')
+
+  AssertEqual
+  \  b:command,
+  \  'mcs -unsafe --parse %t'
+
+Execute(The options should be be used in the command):
+
+  let b:ale_cs_mcs_options = '-pkg:dotnet'
+  let b:command = ale_linters#cs#mcs#GetCommand(bufnr(''))
+  let b:command = substitute(b:command,'\s\+',' ','g')
+
+  AssertEqual
+  \ b:command,
+  \ 'mcs' . b:command_tail . ' ' . b:ale_cs_mcs_options . ' %t',
+
diff --git a/test/command_callback/test_cs_mcsc_command_callbacks.vader b/test/command_callback/test_cs_mcsc_command_callbacks.vader
new file mode 100644
index 00000000..b513b655
--- /dev/null
+++ b/test/command_callback/test_cs_mcsc_command_callbacks.vader
@@ -0,0 +1,120 @@
+Before:
+  Save g:ale_cs_mcsc_options
+  Save g:ale_cs_mcsc_source
+  Save g:ale_cs_mcsc_assembly_path
+  Save g:ale_cs_mcsc_assemblies
+
+  unlet! g:ale_cs_mcsc_options
+  unlet! g:ale_cs_mcsc_source
+  unlet! g:ale_cs_mcsc_assembly_path
+  unlet! g:ale_cs_mcsc_assemblies
+
+  let g:temppath = fnamemodify(tempname(), ':p:h')
+  let g:temppathpattern = substitute(escape(g:temppath, '\\/.*$^~[]'), '[\\/]*$', '[\\\\/]\\+\\S\\+','')
+  let g:sometempfile = fnamemodify(g:temppath .'/some_temp_file.tmp', ':p')
+
+  runtime ale_linters/cs/mcsc.vim
+
+After:
+  Restore
+  unlet! b:ale_cs_mcsc_options
+  unlet! g:ale_cs_mcsc_source
+  unlet! g:ale_cs_mcsc_assembly_path
+  unlet! g:ale_cs_mcsc_assemblies
+  unlet! g:temppath
+  unlet! g:temppathpattern
+  unlet! g:sometempfile
+  call ale#linter#Reset()
+
+Execute(Check for proper default command):
+
+  let b:command = ale_linters#cs#mcsc#GetCommand(bufnr(''))
+  let b:command = substitute(b:command, '-out:' . g:temppathpattern, '-out:' . g:sometempfile, '')
+  let b:command = substitute(b:command, '\s\+', ' ', 'g')
+
+  AssertEqual
+  \   b:command,
+  \   'cd ".";mcs -unsafe -out:' . g:sometempfile . ' -t:module -recurse:"*.cs"'
+
+Execute(The options should be be used in the command):
+
+  let g:ale_cs_mcsc_options = '-pkg:dotnet'
+
+  let b:command = ale_linters#cs#mcsc#GetCommand(bufnr(''))
+  let b:command = substitute(b:command, '-out:' . g:temppathpattern, '-out:' . g:sometempfile, '')
+  let b:command = substitute(b:command, '\s\+', ' ', 'g')
+
+  AssertEqual
+  \   b:command,
+  \   'cd ".";mcs -unsafe ' . g:ale_cs_mcsc_options . ' -out:' . g:sometempfile . ' -t:module -recurse:"*.cs"'
+
+Execute(The souce path should be be used in the command):
+  call ale#engine#Cleanup(bufnr(''))
+  call ale#engine#InitBufferInfo(bufnr(''))
+
+  let g:ale_cs_mcsc_source='../foo/bar'
+
+  let b:command = ale_linters#cs#mcsc#GetCommand(bufnr(''))
+  let b:command = substitute(b:command, '-out:' . g:temppathpattern, '-out:' . g:sometempfile, '')
+  let b:command = substitute(b:command, '\s\+', ' ', 'g')
+
+  AssertEqual
+  \   b:command,
+  \   'cd "' . g:ale_cs_mcsc_source . '";mcs -unsafe -out:' . g:sometempfile . ' -t:module -recurse:"*.cs"'
+
+Execute(The list of search pathes for assemblies should be be used in the command if not empty):
+  call ale#engine#Cleanup(bufnr(''))
+  call ale#engine#InitBufferInfo(bufnr(''))
+
+  let g:ale_cs_mcsc_assembly_path = [
+  \ '/usr/lib/mono',
+  \ '../foo/bar'
+  \]
+
+  let b:command = ale_linters#cs#mcsc#GetCommand(bufnr(''))
+  let b:command = substitute(b:command, '-out:' . g:temppathpattern, '-out:' . g:sometempfile, '')
+  let b:command = substitute(b:command, '\s\+', ' ', 'g')
+
+  AssertEqual
+  \   b:command,
+  \   'cd ".";mcs -unsafe -lib:"' . join(g:ale_cs_mcsc_assembly_path,'","') . '" -out:' . g:sometempfile . ' -t:module -recurse:"*.cs"'
+
+  let g:ale_cs_mcsc_assembly_path = [
+  \]
+
+  let b:command = ale_linters#cs#mcsc#GetCommand(bufnr(''))
+  let b:command = substitute(b:command, '-out:' . g:temppathpattern, '-out:' . g:sometempfile, '')
+  let b:command = substitute(b:command, '\s\+', ' ', 'g')
+
+  AssertEqual
+  \   b:command,
+  \   'cd ".";mcs -unsafe -out:' . g:sometempfile . ' -t:module -recurse:"*.cs"'
+
+Execute(The list of assemblies should be be used in the command if not empty):
+  call ale#engine#Cleanup(bufnr(''))
+  call ale#engine#InitBufferInfo(bufnr(''))
+
+  let g:ale_cs_mcsc_assemblies = [
+  \ 'foo.dll',
+  \ 'bar.dll'
+  \]
+
+  let b:command = ale_linters#cs#mcsc#GetCommand(bufnr(''))
+  let b:command = substitute(b:command, '-out:' . g:temppathpattern, '-out:' . g:sometempfile, '')
+  let b:command = substitute(b:command,'\s\+',' ','g')
+
+  AssertEqual
+  \   b:command,
+  \   'cd ".";mcs -unsafe -r:"' . join(g:ale_cs_mcsc_assemblies,'","') . '" -out:' . g:sometempfile . ' -t:module -recurse:"*.cs"'
+
+  let g:ale_cs_mcsc_assemblies = [
+  \]
+
+  let b:command = ale_linters#cs#mcsc#GetCommand(bufnr(''))
+  let b:command = substitute(b:command, '-out:' . g:temppathpattern, '-out:' . g:sometempfile, '')
+  let b:command = substitute(b:command,'\s\+',' ','g')
+
+  AssertEqual
+  \   b:command,
+  \   'cd ".";mcs -unsafe -out:' . g:sometempfile . ' -t:module -recurse:"*.cs"'
+
diff --git a/test/handler/test_mcs_handler.vader b/test/handler/test_mcs_handler.vader
new file mode 100644
index 00000000..75a764a3
--- /dev/null
+++ b/test/handler/test_mcs_handler.vader
@@ -0,0 +1,34 @@
+Before:
+  runtime ale_linters/cs/mcs.vim
+
+After:
+  call ale#linter#Reset()
+
+Execute(The mcs handler should handle cannot find symbol errors):
+  AssertEqual
+  \ [
+  \   {
+  \     'lnum': 12,
+  \     'col' : 29,
+  \     'text': 'error CS1001: ; expected',
+  \     'type': 'E',
+  \   },
+  \   {
+  \     'lnum': 101,
+  \     'col': 0,
+  \     'text': 'error CS1028: Unexpected processor directive (no #if for this #endif)',
+  \     'type': 'E',
+  \   },
+  \   {
+  \     'lnum': 10,
+  \     'col': 12,
+  \     'text': 'warning CS0123: some warning',
+  \     'type': 'W',
+  \   },
+  \ ],
+  \ ale_linters#cs#mcs#Handle(347, [
+  \   'Tests.cs(12,29): error CS1001: ; expected',
+  \   'Tests.cs(101,0): error CS1028: Unexpected processor directive (no #if for this #endif)',
+  \   'Tests.cs(10,12): warning CS0123: some warning',
+  \   'Compilation failed: 2 error(s), 1 warnings',
+  \ ])
diff --git a/test/handler/test_mcsc_handler.vader b/test/handler/test_mcsc_handler.vader
new file mode 100644
index 00000000..a65185ca
--- /dev/null
+++ b/test/handler/test_mcsc_handler.vader
@@ -0,0 +1,44 @@
+Before:
+  Save g:ale_cs_mcsc_source
+
+  unlet! g:ale_cs_mcsc_source
+
+  runtime ale_linters/cs/mcsc.vim
+
+After:
+  unlet! g:ale_cs_mcsc_source
+  call ale#linter#Reset()
+
+Execute(The mcs handler should handle cannot find symbol errors):
+  let g:ale_cs_mcsc_source='/home/foo/project/bar'
+
+  AssertEqual
+  \ [
+  \   {
+  \     'lnum': 12,
+  \     'col' : 29,
+  \     'text': 'error CS1001: ; expected',
+  \     'type': 'E',
+  \     'filename': '/home/foo/project/bar/Test.cs'
+  \   },
+  \   {
+  \     'lnum': 101,
+  \     'col': 0,
+  \     'text': 'error CS1028: Unexpected processor directive (no #if for this #endif)',
+  \     'type': 'E',
+  \     'filename': '/home/foo/project/bar/Test.cs'
+  \   },
+  \   {
+  \     'lnum': 10,
+  \     'col': 12,
+  \     'text': 'warning CS0123: some warning',
+  \     'type': 'W',
+  \     'filename': '/home/foo/project/bar/Test.cs'
+  \   },
+  \ ],
+  \ ale_linters#cs#mcsc#Handle(347, [
+  \   'Test.cs(12,29): error CS1001: ; expected',
+  \   'Test.cs(101,0): error CS1028: Unexpected processor directive (no #if for this #endif)',
+  \   'Test.cs(10,12): warning CS0123: some warning',
+  \   'Compilation failed: 2 error(s), 1 warnings',
+  \ ])