ambrevar/shell: Add match-directory and walk.

.local/share/common-lisp/source/ambrevar/shell.lisp

@@ -37,9 +37,28 @@ Useful for `finder'."
             (string= ext (pathname-type file)))
           (cons extension more-extensions))))
 
-(export-always 'finder)
-(defun finder (root &rest predicates)
-  "List files in directory that satisfy all PREDICATES.
+(export-always 'match-directory)
+(defun match-directory (&key (empty? t) (non-empty? t) (files? t))
+  "Return a predicate that matches on directories.
+If target is a file, return FILES?.
+Useful for `walk'."
+  (lambda (directory)
+    (if (uiop:directory-exists-p directory)
+        (let ((recursive-files? (or (uiop:directory-files directory)
+                                    (uiop:subdirectories directory))))
+          (or (and empty?
+                   (not files-or-dirs?))
+              (and non-empty?
+                   files-or-dirs?)))
+        files?)))
+
+(export-always '*finder-include-directories*)
+(defvar *finder-include-directories* t
+  "When non-nil `walk' include directories.")
+
+(export-always 'walk)
+(defun walk (root &rest predicates)
+  "List files and directories that satisfy all PREDICATES.
 Without PREDICATES, list all files."
   (let ((result '()))
     (uiop:collect-sub*directories
@@ -47,7 +66,8 @@ Without PREDICATES, list all files."
      (constantly t) (constantly t)
      (lambda (subdirectory)
        (setf result (nconc result
-                           (let ((subfiles (uiop:directory-files subdirectory)))
+                           (let ((subfiles (append (if *finder-include-directories* (list subdirectory) nil)
+                                                   (uiop:directory-files subdirectory))))
                              (if predicates
                                  (delete-if (lambda (file)
                                               (notany (lambda (pred) (funcall pred file))
@@ -56,6 +76,13 @@ Without PREDICATES, list all files."
                                  subfiles))))))
     result))
 
+(export-always 'finder)
+(defun finder (root &rest predicates)
+  "List files in ROOT that satisfy all PREDICATES.
+Without PREDICATES, list all files."
+  (let ((*finder-include-directories* nil))
+    (apply #'walk root predicates)))
+
 (export-always 'make-directory)
 (defun make-directory (path)
   "Including parents."