fix: add check if wrong filetype is detected

Signed-off-by: Thomas Lambert <t.lambert@uliege.be>

+af_tools/+utils/appendextension.m

@@ -9,8 +9,13 @@ function str = appendextension(str, ext)
 
     % ----------------------------------------------------------------------------------------------
 
-    if isempty(regexp(str, [ext, '$'], 'once'))
+    [~, ~, fileExt] = fileparts(str);
+    if isempty(fileExt)
         str = strcat(str, ext);
+    elseif ~isempty(fileExt) && ~strcmp(fileExt, ext)
+        error('MATLAB:appendextension:IncorrectExtension', ...
+              'Incorrect extension. File %s is expected to be a ''%s''. Found ''%s''.', ...
+              str, ext, fileExt);
     end
 
 end

CHANGELOG.md

@@ -25,6 +25,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **formatairfoilcoord**: fix issue with autosave
 - **xf2mat**: add error when input is not a proper xfoil/xflr5 result
 - **plotpolar**: fix issue when unavailable data
+- **all**: add check if wrong filetype is detected
 
 ## [4.0.0] - 2022-06-09