Implement searching wiki link under project root

CHANGES.md

@@ -11,6 +11,7 @@
     -   Option to inhibit the prompt for a tooltip text via
         `markdown-disable-tooltip-prompt`.
     -   Introduce `markdown-ordered-list-enumeration` variable [GH-587][]
+    -   Search wiki link under project
 
 *   Improvements:
     -   Correct indirect buffer's indentation in `markdown-edit-code-block` [GH-375][]

README.md

@@ -931,13 +931,12 @@ are also supported.  Since some wikis reverse these components, set
 is also non-nil, Markdown Mode will highlight wiki links with
 missing target file in a different color.  By default, Markdown
 Mode only searches for target files in the current directory.
-Search in subdirectories can be enabled by setting
-`markdown-wiki-link-search-subdirectories` to a non-nil value.
-Sequential parent directory search (as in [Ikiwiki][]) can be
-enabled by setting `markdown-wiki-link-search-parent-directories`
-to a non-nil value.
+You can control search type by setting `markdown-wiki-link-search-type`.
+This value type is a symbol list. Possible values are
 
-[Ikiwiki]: https://ikiwiki.info
+- `sub-directories` : search in sub directories
+- `parent-directories` : search in parent directories
+- `project` : search under project root
 
 [SmartyPants][] support is possible by customizing `markdown-command`.
 If you install `SmartyPants.pl` at, say, `/usr/local/bin/smartypants`,

markdown-mode.el

@@ -48,6 +48,8 @@
 (defvar flyspell-generic-check-word-predicate)
 (defvar electric-pair-pairs)
 
+(declare-function project-roots "project")
+
 
 ;;; Constants =================================================================
 
@@ -243,6 +245,22 @@ This is the default search behavior of Ikiwiki."
   :safe 'booleanp
   :package-version '(markdown-mode . "2.2"))
 
+(defcustom markdown-wiki-link-search-type nil
+  "Searching type for markdown wiki link.
+
+sub-directories: search for wiki link targets in sub directories
+parent-directories: search for wiki link targets in parent directories
+project: search for wiki link targets under project root"
+  :group 'markdown
+  :type '(set
+          (const :tag "search wiki link from subdirectories" sub-directories)
+          (const :tag "search wiki link from parent directories" parent-directories)
+          (const :tag "search wiki link under project root" project))
+  :package-version '(markdown-mode . "2.5"))
+
+(make-obsolete-variable 'markdown-wiki-link-search-subdirectories 'markdown-wiki-link-search-type "2.5")
+(make-obsolete-variable 'markdown-wiki-link-search-parent-directories 'markdown-wiki-link-search-type "2.5")
+
 (defcustom markdown-wiki-link-fontify-missing nil
   "When non-nil, change wiki link face according to existence of target files.
 This is expensive because it requires checking for the file each time the buffer
@@ -7830,6 +7848,25 @@ The location of the alias component depends on the value of
       (match-string-no-properties 3)
     (or (match-string-no-properties 5) (match-string-no-properties 3))))
 
+(defun markdown--wiki-link-search-types ()
+  (let ((ret (and markdown-wiki-link-search-type
+                  (cl-copy-list markdown-wiki-link-search-type))))
+    (when (and markdown-wiki-link-search-subdirectories
+               (not (memq 'sub-directories markdown-wiki-link-search-type)))
+      (push 'sub-directories ret))
+    (when (and markdown-wiki-link-search-parent-directories
+               (not (memq 'parent-directories markdown-wiki-link-search-type)))
+      (push 'parent-directories ret))
+    ret))
+
+(defun markdown--project-root ()
+  (or (cl-loop for dir in '(".git" ".hg" ".svn")
+               when (locate-dominating-file default-directory dir)
+               return it)
+      (progn
+        (require 'project)
+        (car (project-roots (project-current t))))))
+
 (defun markdown-convert-wiki-link-to-filename (name)
   "Generate a filename from the wiki link NAME.
 Spaces in NAME are replaced with `markdown-link-space-sub-char'.
@@ -7847,6 +7884,7 @@ in parent directories if
                          (concat (upcase (substring basename 0 1))
                                  (downcase (substring basename 1 nil)))
                        basename))
+           (search-types (markdown--wiki-link-search-types))
            directory extension default candidates dir)
       (when buffer-file-name
         (setq directory (file-name-directory buffer-file-name)
@@ -7859,15 +7897,20 @@ in parent directories if
             (file-exists-p default))
         default)
        ;; Possibly search in subdirectories, next.
-       ((and markdown-wiki-link-search-subdirectories
+       ((and (memq 'sub-directories search-types)
              (setq candidates
                    (directory-files-recursively
                     directory (concat "^" default "$"))))
         (car candidates))
        ;; Possibly search in parent directories as a last resort.
-       ((and markdown-wiki-link-search-parent-directories
+       ((and (memq 'parent-directories search-types)
              (setq dir (locate-dominating-file directory default)))
         (concat dir default))
+       ((and (memq 'project search-types)
+             (setq candidates
+                   (directory-files-recursively
+                    (markdown--project-root) (concat "^" default "$"))))
+        (car candidates))
        ;; If nothing is found, return default in current directory.
        (t default)))))
 

tests/markdown-test.el

@@ -6365,10 +6365,29 @@ Detail: https://github.com/jrblevin/markdown-mode/pull/590"
             (markdown-mode)
             (re-search-forward "Zettel Markdown")
             (goto-char (match-beginning 0))
-            (should (markdown-wiki-link-p))
+            (should (markdown-wiki-link-p)) ;; create match-data
             (should (string= (markdown-wiki-link-link) "Zettel Markdown")))
         (kill-buffer)))))
 
+(ert-deftest test-markdown-ext/wiki-link-search-under-project ()
+  "Test that searching link under project root."
+  (let ((markdown-enable-wiki-links t)
+        (markdown-link-space-sub-char " ")
+        (markdown-wiki-link-search-type '(project))
+        (expected (concat (expand-file-name default-directory)
+                          "wiki/pr590/Guide/Zettel Markdown/math.md")))
+    (progn
+      (find-file "wiki/pr590/Guide/Plugin/Link.md")
+      (unwind-protect
+          (progn
+            (markdown-mode)
+            (re-search-forward "math")
+            (goto-char (match-beginning 0))
+            (markdown-wiki-link-p) ;; create match-data
+            (let ((link (markdown-convert-wiki-link-to-filename (markdown-wiki-link-link))))
+              (should (string= (expand-file-name link) expected))))
+        (kill-buffer)))))
+
 (ert-deftest test-markdown-ext/wiki-link-major-mode ()
   "Test major-mode of linked page."
   (let ((markdown-enable-wiki-links t)

tests/wiki/pr590/Guide/Plugin/Link.md

@@ -0,0 +1 @@
+[[math]]