buildfile: validate arguments

Author: scivision

buildfile.m

@@ -68,7 +68,7 @@
                          Tag="python", ...
                          SourceFiles=pkg_root, RunOnlyImpactedTests=true,...
                          TestResults="TestResults_python.xml", Strict=true);
- 
+
   addons = matlab.addons.installedAddons;
   if contains(addons.Name, "Matlab Test")
     plan("coverage") = matlab.buildtool.tasks.TestTask(test_root, ...
@@ -189,6 +189,13 @@ function build_exe(context)
 
 
 function [comp, shell] = get_compiler(lang)
+arguments (Input)
+  lang (1,1) string {mustBeMember(lang, ["c", "c++", "fortran"])}
+end
+arguments (Output)
+  comp (1,1) string
+  shell (1,1) string
+end
 
 lang = lower(lang);
 
@@ -211,14 +218,13 @@ function build_exe(context)
       if isempty(comp)
         disp("set CC environment variable to the C compiler path, or do 'mex -setup c'")
       end
-    otherwise, error("language not known " + lang)
   end
 else
   comp = co.Details.CompilerExecutable;
   % disp(lang + " compiler: " + co.ShortName + " " + co.Name + " " + co.Version + " " + comp)
 end
 
-shell = string.empty;
+shell = "";
 if ispc()
   if isempty(co)
     if any(contains(comp, ["gcc", "g++", "gfortran"]))
@@ -238,6 +244,14 @@ function build_exe(context)
 
 
 function [comp, shell, outFlag] = get_build_cmd(lang)
+arguments (Input)
+  lang (1,1) string {mustBeMember(lang, ["c", "c++", "fortran"])}
+end
+arguments (Output)
+  comp (1,1) string
+  shell (1,1) string
+  outFlag (1,1) string
+end
 
 [comp, shell] = get_compiler(lang);
 
@@ -251,9 +265,12 @@ function build_exe(context)
 
 
 function srcs = get_mex_sources(build_all)
-arguments
+arguments (Input)
   build_all (1,1) logical = false
 end
+arguments (Output)
+  srcs cell
+end
 
 srcs = {
 "src/remove.cpp", ...
@@ -272,6 +289,10 @@ function build_exe(context)
 
 
 function [compiler_opt, linker_opt] = get_compiler_options()
+arguments (Output)
+  compiler_opt (1,1) string
+  linker_opt (1,1) string
+end
 
 cxx = mex.getCompilerConfigurations('c++');
 flags = cxx.Details.CompilerFlags;
@@ -318,6 +339,9 @@ function build_exe(context)
 
 
 function comp = get_fortran_compiler()
+arguments (Output)
+  comp (1,1) string
+end
 
 disp("set FC environment variable to the Fortran compiler path, or do 'mex -setup fortran'")
 
@@ -338,6 +362,7 @@ function build_exe(context)
   p = '';
 end
 
+comp = "";
 for fc = ["flang", "gfortran", "ifx"]
   comp = stdlib.which(fc, p);
   if ~isempty(comp)