Make directory argument mandatory in hasktags command composer

Author: geraldus

haskell-cabal.el

@@ -1079,52 +1079,45 @@ buffer not visiting a file returns nil."
       (when buffer-file-name
         (file-name-directory buffer-file-name))))
 
-(defun haskell-cabal--compose-hasktags-command (&optional cabal-dir)
-  "Prepare command to execute hasktags for current file.
+(defun haskell-cabal--compose-hasktags-command (dir)
+  "Prepare command to execute `hasktags` command in DIR folder.
 By default following parameters are passed to Hasktags
 executable:
 -e - generate ETAGS file
 -x - generate additional information in CTAGS file.
 
-Tries to find cabal file location, give optional CABAL-DIR parameter to
-override it.  If cabal file not found uses current file
-directory if current buffer is visiting a file.  Otherwise returns nil.
-
 This function takes into account user's operation system: in case
-of Windows it generates simple command like
+of Windows it generates simple command, relying on Hasktags
+itself to find source files:
 
 hasktags --output=DIR\TAGS -x -e DIR
 
-relying on Hasktags itself to find source files;
-
 In other cases it uses `find` command to find all source files
 recursively avoiding visiting unnecessary heavy directories like
 .git, .svn, _darcs and build directories created by
-cabal-install, stack, etc."
-  (let ((dir (or cabal-dir (haskell-cabal--find-tags-dir))))
-    (when dir
-      (if (eq system-type 'windows-nt)
-          (format "hasktags --output=\"%s\\TAGS\" -x -e \"%s\"" dir dir)
-        (format "cd %s && %s | %s"
-                dir
-                (concat "find . "
-                        "-type d \\( "
-                        "-path ./.git "
-                        "-o -path ./.svn "
-                        "-o -path ./_darcs "
-                        "-o -path ./.stack-work "
-                        "-o -path ./dist "
-                        "-o -path ./.cabal-sandbox "
-                        "\\) -prune "
-                        "-o -type f \\( "
-                        "-name '*.hs' "
-                        "-or -name '*.lhs' "
-                        "-or -name '*.hsc' "
-                        "\\) -not \\( "
-                        "-name '#*' "
-                        "-or -name '.*' "
-                        "\\) -print0")
-                "xargs -0 hasktags -e -x")))))
+cabal-install, stack, etc and passes list of found files to Hasktags."
+  (if (eq system-type 'windows-nt)
+      (format "hasktags --output=\"%s\\TAGS\" -x -e \"%s\"" dir dir)
+    (format "cd %s && %s | %s"
+            dir
+            (concat "find . "
+                    "-type d \\( "
+                    "-path ./.git "
+                    "-o -path ./.svn "
+                    "-o -path ./_darcs "
+                    "-o -path ./.stack-work "
+                    "-o -path ./dist "
+                    "-o -path ./.cabal-sandbox "
+                    "\\) -prune "
+                    "-o -type f \\( "
+                    "-name '*.hs' "
+                    "-or -name '*.lhs' "
+                    "-or -name '*.hsc' "
+                    "\\) -not \\( "
+                    "-name '#*' "
+                    "-or -name '.*' "
+                    "\\) -print0")
+            "xargs -0 hasktags -e -x")))
 
 (provide 'haskell-cabal)
 ;;; haskell-cabal.el ends here