[Enhancement] Add Unit Test for character Procedures

.justfile

@@ -37,29 +37,39 @@ alias build     := library
 alias clr       := clear
 alias d         := doxygen
 alias l         := library
+alias v         := valgrind
 alias ver       := bump
 alias version   := bump
 
 
 
 # Compiler flags.
+exe     := '-fPIE'
 f18     := '-std=f2018'
 flags   := '-Wall -Werror -Wextra -Wpedantic'
 lib     := '-c -fPIC'
 
-# Targets.
-library := 'libcndmem.a'
+# Linker flags.
+lflags  := '-L. -lf18cndmem'
 
 # Settings for the supported language modes.
+f18-exe := f18 + ' ' + exe + ' ' + flags
 f18-lib := f18 + ' ' + lib + ' ' + flags
+lnk-f18 := '-I. ' + lflags
+
+# Targets.
+library := 'libf18cndmem.a'
+
+# Valgrind settings.
+vflags  := '--leak-check=full --redzone-size=512 --show-leak-kinds=all'
 
 
 
 # The default recipe to execute.
 @default: all
 
 # Execute all configured recipes.
-@all: clear doxygen library
+@all: clear doxygen valgrind
 
 # Increment the version numbers.
 @bump part:
@@ -80,6 +90,10 @@ f18-lib := f18 + ' ' + lib + ' ' + flags
     ar rsv {{library}} *.o
     rm -rf *.o
 
+# Create the required directories.
+@directories:
+    mkdir -p target/
+
 # Create the Doxygen documentation for this project.
 @doxygen:
     doxygen doxygen.cfg
@@ -93,4 +107,14 @@ f18-lib := f18 + ' ' + lib + ' ' + flags
 # Compile the target library.
 @library: character
 
+# Compile and run a single unit test.
+@test name: directories library
+    gfortran {{f18-exe}} tests/test_{{name}}.f08 -o \
+        target/test_{{name}} {{lnk-f18}}
+    valgrind {{vflags}} target/test_{{name}}
+
+# Analyse the memory management of the unit tests.
+@valgrind:
+    just test character
+
 ################################################################################

README.md

@@ -75,6 +75,7 @@ version is as follows:
 | Latexmk           | application   | LaTeX compilation of Doxygen manual   |
 | Scriv             | Python CLI    | changelog management                  |
 | TeX Live (full)   | package       | LaTeX environment for Doxygen manual  |
+| Valgrind          | application   | memory leak detection                 |
 
 This library is written in Fortran 2018 such that its build requires a compiler
 supporting this standard.  This project relies on **GFortran** therefore.
@@ -94,6 +95,10 @@ In order to finalise the LaTeX documentation, an appropriate LaTeX distribution
 is required.  A *full* installation of **TeX Live** is recommended.  This
 project employs **Latexmk** as LaTeX build manager for the manual finalisation.
 
+There are unit tests for the library logic written in plain Fortran 2018 without
+requiring any further libraries.  When running the tests, **Valgrind** will
+analyse their memory management.
+
 In order to simplify the maintenance, **bump2version** as well as **Scriv** are
 used to automate the release generation.  Scriv will compile the changelog on
 release after all version numbers were incremented by bump2version.
@@ -155,8 +160,18 @@ just d
 just doxygen
 ```
 
+The correctness of this library is ensured by a set of unit tests.  They are
+furthermore analysed for their memory management by Valgrind.  By calling for
+the Valgrind analysis, the unit tests are executed implicitly.  This can be
+done with one of the following commands.
+
+```bash
+just v
+just valgrind
+```
+
 If the compilation of both the library and its documentation is wished, the
-following instructions can be executed.
+following instructions can be executed.  This will also run all unit tests.
 
 ```bash
 just

changelog.d/feature:unit-test-character.rst

@@ -0,0 +1,6 @@
+Added
+.....
+
+- unit test:  conditional allocation (type ``character``, default)
+
+- unit test:  conditional deallocation (type ``character``, default)

doxygen.cfg

@@ -907,7 +907,8 @@ WARN_LOGFILE           =
 # Note: If this tag is empty the current directory is searched.
 
 INPUT                  =    src/                \
-                            src/type_character/
+                            src/type_character/ \
+                            tests/
 
 # This tag can be used to specify the character encoding of the source files
 # that doxygen parses. Internally doxygen uses the UTF-8 encoding. Doxygen uses

src/lib.f08

@@ -43,7 +43,7 @@
 !!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
-module libcndmem
+module libf18cndmem
 implicit none
 private
     !> This library's version.
@@ -66,6 +66,6 @@ pure module subroutine cnddel_character (tgt)
             character (:), allocatable, intent (inout)  :: tgt
         end subroutine cnddel_character
     end interface cnddel
-end module libcndmem
+end module libf18cndmem
 
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

src/type_character.f08

@@ -39,7 +39,7 @@
 !!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
-submodule (libcndmem) type_character
+submodule (libf18cndmem) type_character
 implicit none
 contains
     include 'type_character/cndall_character.f08'

tests/test_character.f08

@@ -0,0 +1,105 @@
+!!!!!!!!!!!!!!!!!!!!!!!! GNU General Public License 2.0 !!!!!!!!!!!!!!!!!!!!!!!!
+!!                                                                            !!
+!! Copyright (C) 2022 Kevin Matthes                                           !!
+!!                                                                            !!
+!! This program is free software; you can redistribute it and/or modify       !!
+!! it under the terms of the GNU General Public License as published by       !!
+!! the Free Software Foundation; either version 2 of the License, or          !!
+!! (at your option) any later version.                                        !!
+!!                                                                            !!
+!! This program is distributed in the hope that it will be useful,            !!
+!! but WITHOUT ANY WARRANTY; without even the implied warranty of             !!
+!! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the              !!
+!! GNU General Public License for more details.                               !!
+!!                                                                            !!
+!! You should have received a copy of the GNU General Public License along    !!
+!! with this program; if not, write to the Free Software Foundation, Inc.,    !!
+!! 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.                !!
+!!                                                                            !!
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+!!
+!> \file test_character.f08
+!!
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+!!
+!> \author      Kevin Matthes
+!> \copyright   GPL-2.0
+!> \date        2022
+!> \note        See `LICENSE' for full license.
+!>              See `README.md' for project details.
+!>
+!> \brief   A set of simple tests for the `character` type (default).
+!> \return  Whether this test succeeds.
+!>
+!> This unit test will check whether
+!>
+!> * an unallocated allocatable object can be deallocated.
+!> * an unallocated allocatable object can be allocated and receive a constant.
+!> * an allocated allocatable object can receive another constant by conditional
+!>   reallocation.
+!> * an allocated allocatable object can be deallocated.
+!!
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+program test_character
+    use, non_intrinsic :: libf18cndmem, only: cndall
+    use, non_intrinsic :: libf18cndmem, only: cnddel
+implicit none
+    character (:), allocatable  :: object
+    character (*), parameter    :: constant                                    &
+                                =  'constant'
+    character (*), parameter    :: error_allocated                             &
+                                =  'Allocatable object should not be allocated!'
+    character (*), parameter    :: error_not_allocated                         &
+                                =  'Allocatable object should be allocated!'
+    character (*), parameter    :: error_wrong_value                           &
+                                =  'Allocatable object does not have the expect&
+                                   &ed value!'
+    character (*), parameter    :: hello                                       &
+                                =  'Hello'
+    character (*), parameter    :: world                                       &
+                                =  ', World!'
+    intrinsic                   :: allocated
+
+    if (allocated (object)) then
+        error stop error_allocated
+    else
+        call cnddel (object)
+    end if
+
+    if (allocated (object)) then
+        error stop error_allocated
+    else
+        call cndall (object, constant)
+    end if
+
+    if (.not. allocated (object)) then
+        error stop error_not_allocated
+    else if (object /= constant) then
+        error stop error_wrong_value
+    end if
+
+    call cndall (object, hello)
+
+    if (.not. allocated (object)) then
+        error stop error_not_allocated
+    else if (object // world /= hello // world) then
+        error stop error_wrong_value
+    end if
+
+    if (.not. allocated (object)) then
+        error stop error_not_allocated
+    else
+        call cnddel (object)
+    end if
+
+    if (allocated (object)) then
+        error stop error_allocated
+    end if
+end program test_character
+
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!