Fix #168 - Make the Fortran linter more configurable

ale_linters/fortran/gcc.vim

@@ -1,6 +1,15 @@
 " Author: w0rp <devw0rp@gmail.com>
 " Description: gcc for Fortran files
 
+" This option can be set to 0 to use -ffixed-form
+if !exists('g:ale_fortran_gcc_use_free_form')
+    let g:ale_fortran_gcc_use_free_form = 1
+endif
+
+if !exists('g:ale_fortran_gcc_executable')
+    let g:ale_fortran_gcc_executable = 'gcc'
+endif
+
 " Set this option to change the GCC options for warnings for Fortran.
 if !exists('g:ale_fortran_gcc_options')
     let g:ale_fortran_gcc_options = '-Wall'
@@ -52,16 +61,26 @@ function! ale_linters#fortran#gcc#Handle(buffer, lines) abort
     return l:output
 endfunction
 
+function! ale_linters#fortran#gcc#GetExecutable(buffer) abort
+    return g:ale_fortran_gcc_executable
+endfunction
+
 function! ale_linters#fortran#gcc#GetCommand(buffer) abort
-    return 'gcc -S -x f95 -fsyntax-only -ffree-form '
-    \   . g:ale_fortran_gcc_options
-    \   . ' -'
+    let l:layout_option = g:ale_fortran_gcc_use_free_form
+    \   ? '-ffree-form'
+    \   : '-ffixed-form'
+
+    return ale_linters#fortran#gcc#GetExecutable(a:buffer)
+    \   . ' -S -x f95 -fsyntax-only '
+    \   . l:layout_option . ' '
+    \   . g:ale_fortran_gcc_options . ' '
+    \   . '-'
 endfunction
 
 call ale#linter#Define('fortran', {
 \   'name': 'gcc',
 \   'output_stream': 'stderr',
-\   'executable': 'gcc',
+\   'executable_callback': 'ale_linters#fortran#gcc#GetExecutable',
 \   'command_callback': 'ale_linters#fortran#gcc#GetCommand',
 \   'callback': 'ale_linters#fortran#gcc#Handle',
 \})

doc/ale-fortran.txt

@@ -5,6 +5,15 @@ ALE Fortran Integration                                   *ale-fortran-options*
 -------------------------------------------------------------------------------
 gcc                                                           *ale-fortran-gcc*
 
+g:ale_fortran_gcc_executable                     *g:ale_fortran_gcc_executable*
+
+  Type: |String|
+  Default: `'gcc'`
+
+  This variable can be changed to modify the executable used for checking
+  Fortran code with GCC.
+
+
 g:ale_fortran_gcc_options                           *g:ale_fortran_gcc_options*
 
   Type: |String|
@@ -13,5 +22,15 @@ g:ale_fortran_gcc_options                           *g:ale_fortran_gcc_options*
   This variable can be changed to modify flags given to gcc.
 
 
+g:ale_fortran_gcc_use_free_form               *g:ale_fortran_gcc_use_free_form*
+
+  Type: |Number|
+  Default: `1`
+
+  When set to `1`, the `-ffree-form` flag will be used for GCC, to check files
+  with the free form layout. When set to `0`, `-ffixed-form` will be used
+  instead, for checking files with fixed form layouts.
+
+
 -------------------------------------------------------------------------------
   vim:tw=78:ts=2:sts=2:sw=2:ft=help:norl:

test/command_callback/test_gfortran_command_callback.vader

@@ -0,0 +1,31 @@
+Before:
+  runtime ale_linters/fortran/gcc.vim
+
+After:
+  call ale#linter#Reset()
+  let g:ale_fortran_gcc_options = '-Wall'
+  let g:ale_fortran_gcc_use_free_form = 1
+  let g:ale_fortran_gcc_executable = 'gcc'
+
+Execute(The fortran gcc command callback should return the correct default string):
+  AssertEqual 'gcc -S -x f95 -fsyntax-only -ffree-form -Wall -',
+  \ join(split(ale_linters#fortran#gcc#GetCommand(1)))
+
+Execute(The fortran gcc command callback should let you set options):
+  let g:ale_fortran_gcc_options = '-Wotherthings'
+
+  AssertEqual 'gcc -S -x f95 -fsyntax-only -ffree-form -Wotherthings -',
+  \ join(split(ale_linters#fortran#gcc#GetCommand(1)))
+
+Execute(The fortran gcc command callback should let you use -ffixed-form):
+  let g:ale_fortran_gcc_use_free_form = 0
+
+  AssertEqual 'gcc -S -x f95 -fsyntax-only -ffixed-form -Wall -',
+  \ join(split(ale_linters#fortran#gcc#GetCommand(1)))
+
+Execute(The fortran executable should be configurable):
+  let g:ale_fortran_gcc_executable = 'gfortran'
+
+  AssertEqual 'gfortran', ale_linters#fortran#gcc#GetExecutable(1)
+  AssertEqual 'gfortran -S -x f95 -fsyntax-only -ffree-form -Wall -',
+  \ join(split(ale_linters#fortran#gcc#GetCommand(1)))