Refactor fpm_sources: separate out parsing routines

3 files changed, 433 insertions, 420 deletions

diff --git a/fpm/src/fpm_source_parsing.f90 b/fpm/src/fpm_source_parsing.f90
new file mode 100644
index 0000000..abbe716
--- /dev/null
+++ b/fpm/src/fpm_source_parsing.f90
@@ -0,0 +1,425 @@
+module fpm_source_parsing
+use fpm_error, only: error_t, file_parse_error
+use fpm_model, only: srcfile_t, &
+                    FPM_UNIT_UNKNOWN, FPM_UNIT_PROGRAM, FPM_UNIT_MODULE, &
+                    FPM_UNIT_SUBMODULE, FPM_UNIT_SUBPROGRAM, &
+                    FPM_UNIT_CSOURCE, FPM_UNIT_CHEADER
+                    
+use fpm_filesystem, only: basename, read_lines
+use fpm_strings, only: lower, split, str_ends_with, string_t
+implicit none
+
+private
+public :: parse_source, parse_f_source, parse_c_source
+
+character(15), parameter :: INTRINSIC_MODULE_NAMES(*) =  &
+                             ['iso_c_binding  ', &
+                              'iso_fortran_env', &
+                              'ieee_arithmetic', &
+                              'ieee_exceptions', &
+                              'ieee_features  ']
+
+contains
+
+function parse_source(source_file_path,error) result(source)
+    character(*), intent(in) :: source_file_path
+    type(error_t), allocatable, intent(out) :: error
+    type(srcfile_t)  :: source
+
+    if (str_ends_with(lower(source_file_path), ".f90")) then
+
+        source = parse_f_source(source_file_path, error)
+
+        if (source%unit_type == FPM_UNIT_PROGRAM) then
+            source%exe_name = basename(source_file_path,suffix=.false.)
+        end if
+
+    else if (str_ends_with(lower(source_file_path), ".c") .or. &
+        str_ends_with(lower(source_file_path), ".h")) then
+
+        source = parse_c_source(source_file_path,error)
+
+    end if
+
+    if (allocated(error)) then
+        return
+    end if
+
+end function parse_source
+
+function parse_f_source(f_filename,error) result(f_source)
+    ! Rudimentary scan of Fortran source file and 
+    !  extract program unit name and use/include dependencies
+    !
+    character(*), intent(in) :: f_filename
+    type(srcfile_t) :: f_source
+    type(error_t), allocatable, intent(out) :: error
+
+    integer :: stat
+    integer :: fh, n_use, n_include, n_mod, i, j, ic, pass
+    type(string_t), allocatable :: file_lines(:)
+    character(:), allocatable :: temp_string, mod_name
+
+    f_source%file_name = f_filename
+
+    open(newunit=fh,file=f_filename,status='old')
+    file_lines = read_lines(fh)
+    close(fh)
+
+    do pass = 1,2
+        n_use = 0
+        n_include = 0
+        n_mod = 0
+        file_loop: do i=1,size(file_lines)
+
+            ! Skip lines that are continued: not statements
+            if (i > 1) then
+                ic = index(file_lines(i-1)%s,'!')
+                if (ic < 1) then
+                    ic = len(file_lines(i-1)%s)
+                end if
+                temp_string = trim(file_lines(i-1)%s(1:ic))
+                if (len(temp_string) > 0 .and. index(temp_string,'&') == len(temp_string)) then
+                    cycle
+                end if
+            end if
+
+            ! Process 'USE' statements
+            if (index(adjustl(lower(file_lines(i)%s)),'use ') == 1 .or. &
+                index(adjustl(lower(file_lines(i)%s)),'use::') == 1) then
+
+                if (index(file_lines(i)%s,'::') > 0) then
+
+                    temp_string = split_n(file_lines(i)%s,delims=':',n=2,stat=stat)
+                    if (stat /= 0) then
+                        call file_parse_error(error,f_filename, &
+                                'unable to find used module name',i, &
+                                file_lines(i)%s,index(file_lines(i)%s,'::'))
+                        return
+                    end if
+
+                    mod_name = split_n(temp_string,delims=' ,',n=1,stat=stat)
+                    if (stat /= 0) then
+                        call file_parse_error(error,f_filename, &
+                                 'unable to find used module name',i, &
+                                 file_lines(i)%s)
+                        return
+                    end if
+                    mod_name = lower(mod_name)
+
+                else
+
+                    mod_name = split_n(file_lines(i)%s,n=2,delims=' ,',stat=stat)
+                    if (stat /= 0) then
+                        call file_parse_error(error,f_filename, &
+                                'unable to find used module name',i, &
+                                file_lines(i)%s)
+                        return
+                    end if
+                    mod_name = lower(mod_name)
+
+                end if
+
+                if (.not.validate_name(mod_name)) then
+                    cycle
+                end if
+
+                if (any([(index(mod_name,trim(INTRINSIC_MODULE_NAMES(j)))>0, &
+                            j=1,size(INTRINSIC_MODULE_NAMES))])) then
+                    cycle
+                end if
+
+                n_use = n_use + 1
+
+                if (pass == 2) then
+
+                    f_source%modules_used(n_use)%s = mod_name
+
+                end if
+
+            end if
+
+            ! Process 'INCLUDE' statements
+            ic = index(adjustl(lower(file_lines(i)%s)),'include')
+            if ( ic == 1 ) then
+                ic = index(lower(file_lines(i)%s),'include')
+                if (index(adjustl(file_lines(i)%s(ic+7:)),'"') == 1 .or. &
+                    index(adjustl(file_lines(i)%s(ic+7:)),"'") == 1 ) then
+
+    
+                    n_include = n_include + 1
+
+                    if (pass == 2) then
+                        f_source%include_dependencies(n_include)%s = &
+                         & split_n(file_lines(i)%s,n=2,delims="'"//'"',stat=stat)
+                        if (stat /= 0) then
+                            call file_parse_error(error,f_filename, &
+                                  'unable to find include file name',i, &
+                                  file_lines(i)%s)
+                            return
+                        end if
+                    end if
+                end if
+            end if
+
+            ! Extract name of module if is module
+            if (index(adjustl(lower(file_lines(i)%s)),'module ') == 1) then
+
+                mod_name = lower(split_n(file_lines(i)%s,n=2,delims=' ',stat=stat))
+                if (stat /= 0) then
+                    call file_parse_error(error,f_filename, &
+                          'unable to find module name',i, &
+                          file_lines(i)%s)
+                    return
+                end if
+
+                if (mod_name == 'procedure' .or. &
+                    mod_name == 'subroutine' .or. &
+                    mod_name == 'function') then
+                    ! Ignore these cases
+                    cycle
+                end if
+
+                if (.not.validate_name(mod_name)) then
+                    call file_parse_error(error,f_filename, &
+                          'empty or invalid name for module',i, &
+                          file_lines(i)%s, index(file_lines(i)%s,mod_name))
+                    return
+                end if
+
+                n_mod = n_mod + 1
+
+                if (pass == 2) then
+                    f_source%modules_provided(n_mod) = string_t(mod_name)
+                end if
+
+                f_source%unit_type = FPM_UNIT_MODULE
+
+            end if
+
+            ! Extract name of submodule if is submodule
+            if (index(adjustl(lower(file_lines(i)%s)),'submodule') == 1) then
+
+                mod_name = split_n(file_lines(i)%s,n=3,delims='()',stat=stat)
+                if (stat /= 0) then
+                    call file_parse_error(error,f_filename, &
+                          'unable to get submodule name',i, &
+                          file_lines(i)%s)
+                    return
+                end if
+                if (.not.validate_name(mod_name)) then
+                    call file_parse_error(error,f_filename, &
+                          'empty or invalid name for submodule',i, &
+                          file_lines(i)%s, index(file_lines(i)%s,mod_name))
+                    return
+                end if
+
+                n_mod = n_mod + 1
+
+                temp_string = split_n(file_lines(i)%s,n=2,delims='()',stat=stat)
+                if (stat /= 0) then
+                    call file_parse_error(error,f_filename, &
+                          'unable to get submodule ancestry',i, &
+                          file_lines(i)%s)
+                    return
+                end if
+
+                f_source%unit_type = FPM_UNIT_SUBMODULE
+
+                n_use = n_use + 1
+
+                if (pass == 2) then
+
+                    if (index(temp_string,':') > 0) then
+
+                        temp_string = temp_string(index(temp_string,':')+1:)
+                        
+                    end if
+
+                    if (.not.validate_name(temp_string)) then
+                        call file_parse_error(error,f_filename, &
+                          'empty or invalid name for submodule parent',i, &
+                          file_lines(i)%s, index(file_lines(i)%s,temp_string))
+                        return
+                    end if
+
+                    f_source%modules_used(n_use)%s = lower(temp_string)
+
+                    f_source%modules_provided(n_mod)%s = lower(mod_name)
+
+                end if
+
+            end if
+
+            ! Detect if contains a program
+            !  (no modules allowed after program def)
+            if (index(adjustl(lower(file_lines(i)%s)),'program') == 1) then
+
+                f_source%unit_type = FPM_UNIT_PROGRAM
+
+            end if
+
+        end do file_loop
+
+        ! Default to subprogram unit type
+        if (f_source%unit_type == FPM_UNIT_UNKNOWN) then
+            f_source%unit_type = FPM_UNIT_SUBPROGRAM
+        end if
+
+        if (pass == 1) then
+            allocate(f_source%modules_used(n_use))
+            allocate(f_source%include_dependencies(n_include))
+            allocate(f_source%modules_provided(n_mod))
+        end if
+
+    end do
+
+    contains
+
+    function validate_name(name) result(valid)
+        character(*), intent(in) :: name
+        logical :: valid
+
+        integer :: i
+
+        if (len_trim(name) < 1) then
+            valid = .false.
+            return
+        end if
+
+        if (lower(name(1:1)) < 'a' .or. &
+            lower(name(1:1)) > 'z') then
+
+            valid = .false.
+            return
+        end if
+
+        do i=1,len(name)
+
+            if (.not.( &
+                (name(i:i) >= '0' .and. name(i:i) <= '9').or. &
+                (lower(name(i:i)) >= 'a' .and. lower(name(i:i)) <= 'z').or. &
+                name(i:i) == '_') ) then
+                    
+                valid = .false.
+                return
+            end if
+
+        end do
+
+        valid = .true.
+        return
+
+    end function validate_name
+
+end function parse_f_source
+
+
+function parse_c_source(c_filename,error) result(c_source)
+    ! Rudimentary scan of c source file and 
+    !  extract include dependencies
+    !
+    character(*), intent(in) :: c_filename
+    type(srcfile_t) :: c_source
+    type(error_t), allocatable, intent(out) :: error
+
+    integer :: fh, n_include, i, pass, stat
+    type(string_t), allocatable :: file_lines(:)
+
+    c_source%file_name = c_filename
+
+    if (str_ends_with(lower(c_filename), ".c")) then
+
+        c_source%unit_type = FPM_UNIT_CSOURCE
+
+    elseif (str_ends_with(lower(c_filename), ".h")) then
+
+        c_source%unit_type = FPM_UNIT_CHEADER
+
+    end if
+
+    allocate(c_source%modules_used(0))
+    allocate(c_source%modules_provided(0))
+
+    open(newunit=fh,file=c_filename,status='old')
+    file_lines = read_lines(fh)
+    close(fh)
+
+    do pass = 1,2
+        n_include = 0
+        file_loop: do i=1,size(file_lines)
+
+            ! Process 'INCLUDE' statements
+            if (index(adjustl(lower(file_lines(i)%s)),'#include') == 1 .and. &
+                index(file_lines(i)%s,'"') > 0) then
+                            
+                n_include = n_include + 1
+
+                if (pass == 2) then
+
+                    c_source%include_dependencies(n_include)%s = &
+                     &   split_n(file_lines(i)%s,n=2,delims='"',stat=stat)
+                    if (stat /= 0) then
+                        call file_parse_error(error,c_filename, &
+                            'unable to get c include file',i, &
+                            file_lines(i)%s,index(file_lines(i)%s,'"'))
+                        return
+                    end if
+
+                end if
+
+            end if
+
+        end do file_loop
+
+        if (pass == 1) then
+            allocate(c_source%include_dependencies(n_include))
+        end if
+
+    end do
+
+end function parse_c_source
+
+
+function split_n(string,delims,n,stat) result(substring)
+    ! Split a string on one or more delimeters
+    !  and return the nth substring if it exists
+    !
+    ! n=0  will return the last item
+    ! n=-1 will return the penultimate item etc.
+    !
+    ! stat = 1 on return if the index 
+    !  is not found
+    !
+    character(*), intent(in) :: string
+    character(*), intent(in) :: delims
+    integer, intent(in) :: n
+    integer, intent(out) :: stat
+    character(:), allocatable :: substring
+
+    integer :: i
+    character(:), allocatable :: string_parts(:)
+
+    call split(string,string_parts,delims)
+
+    if (n<1) then
+        i = size(string_parts) + n
+        if (i < 1) then
+            stat = 1
+            return
+        end if
+    else
+        i = n
+    end if
+
+    if (i>size(string_parts)) then
+        stat = 1
+        return
+    end if
+
+    substring = trim(adjustl(string_parts(i)))
+    stat = 0
+
+end function split_n
+
+end module fpm_source_parsing
\ No newline at end of file
diff --git a/fpm/src/fpm_sources.f90 b/fpm/src/fpm_sources.f90
index 393c799..6ad8815 100644
--- a/fpm/src/fpm_sources.f90
+++ b/fpm/src/fpm_sources.f90
@@ -1,56 +1,20 @@
 module fpm_sources
-use fpm_error, only: error_t, file_parse_error, fatal_error
-use fpm_model, only: srcfile_ptr, srcfile_t, fpm_model_t, &
-                    FPM_UNIT_UNKNOWN, FPM_UNIT_PROGRAM, FPM_UNIT_MODULE, &
-                    FPM_UNIT_SUBMODULE, FPM_UNIT_SUBPROGRAM, &
-                    FPM_UNIT_CSOURCE, FPM_UNIT_CHEADER, FPM_SCOPE_UNKNOWN, &
+use fpm_error, only: error_t, fatal_error
+use fpm_model, only: srcfile_ptr, srcfile_t, &
+                    FPM_UNIT_PROGRAM, &
                     FPM_SCOPE_LIB, FPM_SCOPE_DEP, FPM_SCOPE_APP, FPM_SCOPE_TEST
                     
-use fpm_filesystem, only: basename, canon_path, dirname, join_path, read_lines, list_files
-use fpm_strings, only: lower, split, str_ends_with, string_t, operator(.in.)
+use fpm_filesystem, only: basename, canon_path, dirname, join_path, list_files
+use fpm_strings, only: lower, str_ends_with, string_t, operator(.in.)
 use fpm_manifest_executable, only: executable_t
+use fpm_source_parsing, only: parse_source
 implicit none
 
 private
-public :: add_sources_from_dir, add_executable_sources
-public :: parse_f_source, parse_c_source, resolve_module_dependencies
-
-character(15), parameter :: INTRINSIC_MODULE_NAMES(*) =  &
-                             ['iso_c_binding  ', &
-                              'iso_fortran_env', &
-                              'ieee_arithmetic', &
-                              'ieee_exceptions', &
-                              'ieee_features  ']
+public :: add_sources_from_dir, add_executable_sources, resolve_module_dependencies
 
 contains
 
-function parse_source(source_file_path,error) result(source)
-    character(*), intent(in) :: source_file_path
-    type(error_t), allocatable, intent(out) :: error
-    type(srcfile_t)  :: source
-
-    if (str_ends_with(lower(source_file_path), ".f90")) then
-
-        source = parse_f_source(source_file_path, error)
-
-        if (source%unit_type == FPM_UNIT_PROGRAM) then
-            source%exe_name = basename(source_file_path,suffix=.false.)
-        end if
-
-    else if (str_ends_with(lower(source_file_path), ".c") .or. &
-        str_ends_with(lower(source_file_path), ".h")) then
-
-        source = parse_c_source(source_file_path,error)
-
-    end if
-
-    if (allocated(error)) then
-        return
-    end if
-
-end function parse_source
-
-
 subroutine add_sources_from_dir(sources,directory,scope,with_executables,error)
     ! Enumerate sources in a directory
     !
@@ -207,382 +171,6 @@ subroutine get_executable_source_dirs(exe_dirs,executables)
 end subroutine get_executable_source_dirs
 
 
-function parse_f_source(f_filename,error) result(f_source)
-    ! Rudimentary scan of Fortran source file and 
-    !  extract program unit name and use/include dependencies
-    !
-    character(*), intent(in) :: f_filename
-    type(srcfile_t) :: f_source
-    type(error_t), allocatable, intent(out) :: error
-
-    integer :: stat
-    integer :: fh, n_use, n_include, n_mod, i, j, ic, pass
-    type(string_t), allocatable :: file_lines(:)
-    character(:), allocatable :: temp_string, mod_name
-
-    f_source%file_name = f_filename
-
-    open(newunit=fh,file=f_filename,status='old')
-    file_lines = read_lines(fh)
-    close(fh)
-
-    do pass = 1,2
-        n_use = 0
-        n_include = 0
-        n_mod = 0
-        file_loop: do i=1,size(file_lines)
-
-            ! Skip lines that are continued: not statements
-            if (i > 1) then
-                ic = index(file_lines(i-1)%s,'!')
-                if (ic < 1) then
-                    ic = len(file_lines(i-1)%s)
-                end if
-                temp_string = trim(file_lines(i-1)%s(1:ic))
-                if (len(temp_string) > 0 .and. index(temp_string,'&') == len(temp_string)) then
-                    cycle
-                end if
-            end if
-
-            ! Process 'USE' statements
-            if (index(adjustl(lower(file_lines(i)%s)),'use ') == 1 .or. &
-                index(adjustl(lower(file_lines(i)%s)),'use::') == 1) then
-
-                if (index(file_lines(i)%s,'::') > 0) then
-
-                    temp_string = split_n(file_lines(i)%s,delims=':',n=2,stat=stat)
-                    if (stat /= 0) then
-                        call file_parse_error(error,f_filename, &
-                                'unable to find used module name',i, &
-                                file_lines(i)%s,index(file_lines(i)%s,'::'))
-                        return
-                    end if
-
-                    mod_name = split_n(temp_string,delims=' ,',n=1,stat=stat)
-                    if (stat /= 0) then
-                        call file_parse_error(error,f_filename, &
-                                 'unable to find used module name',i, &
-                                 file_lines(i)%s)
-                        return
-                    end if
-                    mod_name = lower(mod_name)
-
-                else
-
-                    mod_name = split_n(file_lines(i)%s,n=2,delims=' ,',stat=stat)
-                    if (stat /= 0) then
-                        call file_parse_error(error,f_filename, &
-                                'unable to find used module name',i, &
-                                file_lines(i)%s)
-                        return
-                    end if
-                    mod_name = lower(mod_name)
-
-                end if
-
-                if (.not.validate_name(mod_name)) then
-                    cycle
-                end if
-
-                if (any([(index(mod_name,trim(INTRINSIC_MODULE_NAMES(j)))>0, &
-                            j=1,size(INTRINSIC_MODULE_NAMES))])) then
-                    cycle
-                end if
-
-                n_use = n_use + 1
-
-                if (pass == 2) then
-
-                    f_source%modules_used(n_use)%s = mod_name
-
-                end if
-
-            end if
-
-            ! Process 'INCLUDE' statements
-            ic = index(adjustl(lower(file_lines(i)%s)),'include')
-            if ( ic == 1 ) then
-                ic = index(lower(file_lines(i)%s),'include')
-                if (index(adjustl(file_lines(i)%s(ic+7:)),'"') == 1 .or. &
-                    index(adjustl(file_lines(i)%s(ic+7:)),"'") == 1 ) then
-
-    
-                    n_include = n_include + 1
-
-                    if (pass == 2) then
-                        f_source%include_dependencies(n_include)%s = &
-                         & split_n(file_lines(i)%s,n=2,delims="'"//'"',stat=stat)
-                        if (stat /= 0) then
-                            call file_parse_error(error,f_filename, &
-                                  'unable to find include file name',i, &
-                                  file_lines(i)%s)
-                            return
-                        end if
-                    end if
-                end if
-            end if
-
-            ! Extract name of module if is module
-            if (index(adjustl(lower(file_lines(i)%s)),'module ') == 1) then
-
-                mod_name = lower(split_n(file_lines(i)%s,n=2,delims=' ',stat=stat))
-                if (stat /= 0) then
-                    call file_parse_error(error,f_filename, &
-                          'unable to find module name',i, &
-                          file_lines(i)%s)
-                    return
-                end if
-
-                if (mod_name == 'procedure' .or. &
-                    mod_name == 'subroutine' .or. &
-                    mod_name == 'function') then
-                    ! Ignore these cases
-                    cycle
-                end if
-
-                if (.not.validate_name(mod_name)) then
-                    call file_parse_error(error,f_filename, &
-                          'empty or invalid name for module',i, &
-                          file_lines(i)%s, index(file_lines(i)%s,mod_name))
-                    return
-                end if
-
-                n_mod = n_mod + 1
-
-                if (pass == 2) then
-                    f_source%modules_provided(n_mod) = string_t(mod_name)
-                end if
-
-                f_source%unit_type = FPM_UNIT_MODULE
-
-            end if
-
-            ! Extract name of submodule if is submodule
-            if (index(adjustl(lower(file_lines(i)%s)),'submodule') == 1) then
-
-                mod_name = split_n(file_lines(i)%s,n=3,delims='()',stat=stat)
-                if (stat /= 0) then
-                    call file_parse_error(error,f_filename, &
-                          'unable to get submodule name',i, &
-                          file_lines(i)%s)
-                    return
-                end if
-                if (.not.validate_name(mod_name)) then
-                    call file_parse_error(error,f_filename, &
-                          'empty or invalid name for submodule',i, &
-                          file_lines(i)%s, index(file_lines(i)%s,mod_name))
-                    return
-                end if
-
-                n_mod = n_mod + 1
-
-                temp_string = split_n(file_lines(i)%s,n=2,delims='()',stat=stat)
-                if (stat /= 0) then
-                    call file_parse_error(error,f_filename, &
-                          'unable to get submodule ancestry',i, &
-                          file_lines(i)%s)
-                    return
-                end if
-
-                f_source%unit_type = FPM_UNIT_SUBMODULE
-
-                n_use = n_use + 1
-
-                if (pass == 2) then
-
-                    if (index(temp_string,':') > 0) then
-
-                        temp_string = temp_string(index(temp_string,':')+1:)
-                        
-                    end if
-
-                    if (.not.validate_name(temp_string)) then
-                        call file_parse_error(error,f_filename, &
-                          'empty or invalid name for submodule parent',i, &
-                          file_lines(i)%s, index(file_lines(i)%s,temp_string))
-                        return
-                    end if
-
-                    f_source%modules_used(n_use)%s = lower(temp_string)
-
-                    f_source%modules_provided(n_mod)%s = lower(mod_name)
-
-                end if
-
-            end if
-
-            ! Detect if contains a program
-            !  (no modules allowed after program def)
-            if (index(adjustl(lower(file_lines(i)%s)),'program') == 1) then
-
-                f_source%unit_type = FPM_UNIT_PROGRAM
-
-            end if
-
-        end do file_loop
-
-        ! Default to subprogram unit type
-        if (f_source%unit_type == FPM_UNIT_UNKNOWN) then
-            f_source%unit_type = FPM_UNIT_SUBPROGRAM
-        end if
-
-        if (pass == 1) then
-            allocate(f_source%modules_used(n_use))
-            allocate(f_source%include_dependencies(n_include))
-            allocate(f_source%modules_provided(n_mod))
-        end if
-
-    end do
-
-    contains
-
-    function validate_name(name) result(valid)
-        character(*), intent(in) :: name
-        logical :: valid
-
-        integer :: i
-
-        if (len_trim(name) < 1) then
-            valid = .false.
-            return
-        end if
-
-        if (lower(name(1:1)) < 'a' .or. &
-            lower(name(1:1)) > 'z') then
-
-            valid = .false.
-            return
-        end if
-
-        do i=1,len(name)
-
-            if (.not.( &
-                (name(i:i) >= '0' .and. name(i:i) <= '9').or. &
-                (lower(name(i:i)) >= 'a' .and. lower(name(i:i)) <= 'z').or. &
-                name(i:i) == '_') ) then
-                    
-                valid = .false.
-                return
-            end if
-
-        end do
-
-        valid = .true.
-        return
-
-    end function validate_name
-
-end function parse_f_source
-
-
-function parse_c_source(c_filename,error) result(c_source)
-    ! Rudimentary scan of c source file and 
-    !  extract include dependencies
-    !
-    character(*), intent(in) :: c_filename
-    type(srcfile_t) :: c_source
-    type(error_t), allocatable, intent(out) :: error
-
-    integer :: fh, n_include, i, pass, stat
-    type(string_t), allocatable :: file_lines(:)
-
-    c_source%file_name = c_filename
-
-    if (str_ends_with(lower(c_filename), ".c")) then
-
-        c_source%unit_type = FPM_UNIT_CSOURCE
-
-    elseif (str_ends_with(lower(c_filename), ".h")) then
-
-        c_source%unit_type = FPM_UNIT_CHEADER
-
-    end if
-
-    allocate(c_source%modules_used(0))
-    allocate(c_source%modules_provided(0))
-
-    open(newunit=fh,file=c_filename,status='old')
-    file_lines = read_lines(fh)
-    close(fh)
-
-    do pass = 1,2
-        n_include = 0
-        file_loop: do i=1,size(file_lines)
-
-            ! Process 'INCLUDE' statements
-            if (index(adjustl(lower(file_lines(i)%s)),'#include') == 1 .and. &
-                index(file_lines(i)%s,'"') > 0) then
-                            
-                n_include = n_include + 1
-
-                if (pass == 2) then
-
-                    c_source%include_dependencies(n_include)%s = &
-                     &   split_n(file_lines(i)%s,n=2,delims='"',stat=stat)
-                    if (stat /= 0) then
-                        call file_parse_error(error,c_filename, &
-                            'unable to get c include file',i, &
-                            file_lines(i)%s,index(file_lines(i)%s,'"'))
-                        return
-                    end if
-
-                end if
-
-            end if
-
-        end do file_loop
-
-        if (pass == 1) then
-            allocate(c_source%include_dependencies(n_include))
-        end if
-
-    end do
-
-end function parse_c_source
-
-
-function split_n(string,delims,n,stat) result(substring)
-    ! Split a string on one or more delimeters
-    !  and return the nth substring if it exists
-    !
-    ! n=0  will return the last item
-    ! n=-1 will return the penultimate item etc.
-    !
-    ! stat = 1 on return if the index 
-    !  is not found
-    !
-    character(*), intent(in) :: string
-    character(*), intent(in) :: delims
-    integer, intent(in) :: n
-    integer, intent(out) :: stat
-    character(:), allocatable :: substring
-
-    integer :: i
-    character(:), allocatable :: string_parts(:)
-
-    call split(string,string_parts,delims)
-
-    if (n<1) then
-        i = size(string_parts) + n
-        if (i < 1) then
-            stat = 1
-            return
-        end if
-    else
-        i = n
-    end if
-
-    if (i>size(string_parts)) then
-        stat = 1
-        return
-    end if
-
-    substring = trim(adjustl(string_parts(i)))
-    stat = 0
-
-end function split_n
-
-
 subroutine resolve_module_dependencies(sources,error)
     ! After enumerating all source files: resolve file dependencies
     !  by searching on module names
diff --git a/fpm/test/fpm_test/test_source_parsing.f90 b/fpm/test/fpm_test/test_source_parsing.f90
index d1d3e12..4463c07 100644
--- a/fpm/test/fpm_test/test_source_parsing.f90
+++ b/fpm/test/fpm_test/test_source_parsing.f90
@@ -2,7 +2,7 @@
 module test_source_parsing
     use testsuite, only : new_unittest, unittest_t, error_t, test_failed
     use fpm_filesystem, only: get_temp_filename
-    use fpm_sources, only: parse_f_source, parse_c_source
+    use fpm_source_parsing, only: parse_f_source, parse_c_source
     use fpm_model, only: srcfile_t, FPM_UNIT_PROGRAM, FPM_UNIT_MODULE, &
                          FPM_UNIT_SUBMODULE, FPM_UNIT_SUBPROGRAM, FPM_UNIT_CSOURCE
     use fpm_strings, only: operator(.in.)