feat: render inline code spans verbatim in the Org buffer

A fetched description with markdown inside backticks — `**bold**`, `[text](url)`, `_italic_` — got its span contents converted along with the surrounding prose, so the Org buffer showed `*bold*` and `[[url][text]]` inside what should read as literal code. Markdown treats a code span as opaque; the converter didn't.

Both converters now tokenize code spans first and apply link/bold/italic conversion only to the text between them, keeping span contents literal. The md->org and org->md directions each split into an emphasis-only helper (pearl--md-emphasis-to-org, pearl--org-emphasis-to-md) called on the gaps, with the span passed through untouched. Keeping the split symmetric is what preserves the round-trip identity a fetch + no-edit push depends on.

A new test asserts the verbatim rendering for bold, link, and italic inside a span, plus emphasis still converting outside one and between two spans.

1 files changed, 59 insertions, 32 deletions

diff --git a/pearl.el b/pearl.el
index 844b9f0..4111557 100644
--- a/pearl.el
+++ b/pearl.el
@@ -1674,23 +1674,37 @@ PRIORITY-NUM is 0=None, 1=Urgent, 2=High, 3=Medium, 4=Low."
    ((eq priority-num 4) "Low")
    (t "Medium")))
 
+(defun pearl--md-emphasis-to-org (s)
+  "Convert markdown links / bold / italic in S to Org markup.
+S must contain no inline code spans -- those are handled by the caller, which
+splits them out so their contents stay verbatim."
+  ;; [text](url) -> [[url][text]]
+  (setq s (replace-regexp-in-string
+           "\\[\\([^]]+\\)\\](\\([^) ]+\\))" "[[\\2][\\1]]" s))
+  ;; **bold** -> *bold*
+  (setq s (replace-regexp-in-string "\\*\\*\\([^*\n]+?\\)\\*\\*" "*\\1*" s))
+  ;; _italic_ -> /italic/, word-bounded so identifiers like foo_bar are left alone
+  (setq s (replace-regexp-in-string
+           "\\(^\\|[^[:alnum:]_]\\)_\\([^_\n]+?\\)_\\([^[:alnum:]_]\\|$\\)"
+           "\\1/\\2/\\3" s))
+  s)
+
 (defun pearl--md-line-to-org (line)
   "Convert inline markdown in LINE to Org markup.
 Handles links, inline code, bold, and underscore italics; other inline markup
-passes through unchanged."
-  (let ((s line))
-    ;; [text](url) -> [[url][text]]   (before code/emphasis touch the brackets)
-    (setq s (replace-regexp-in-string
-             "\\[\\([^]]+\\)\\](\\([^) ]+\\))" "[[\\2][\\1]]" s))
-    ;; `code` -> ~code~
-    (setq s (replace-regexp-in-string "`\\([^`\n]+\\)`" "~\\1~" s))
-    ;; **bold** -> *bold*
-    (setq s (replace-regexp-in-string "\\*\\*\\([^*\n]+?\\)\\*\\*" "*\\1*" s))
-    ;; _italic_ -> /italic/, word-bounded so identifiers like foo_bar are left alone
-    (setq s (replace-regexp-in-string
-             "\\(^\\|[^[:alnum:]_]\\)_\\([^_\n]+?\\)_\\([^[:alnum:]_]\\|$\\)"
-             "\\1/\\2/\\3" s))
-    s))
+passes through unchanged.  Inline code spans are tokenized first and their
+contents kept verbatim, so markdown-looking text in backticks (`**b**`,
+`[l](u)`) renders as code rather than being converted."
+  (let ((result "")
+        (pos 0))
+    (while (string-match "`\\([^`\n]+\\)`" line pos)
+      ;; emphasis/links on the text before this code span, then the span verbatim
+      (setq result (concat result
+                           (pearl--md-emphasis-to-org
+                            (substring line pos (match-beginning 0)))
+                           "~" (match-string 1 line) "~"))
+      (setq pos (match-end 0)))
+    (concat result (pearl--md-emphasis-to-org (substring line pos)))))
 
 (defun pearl--md-to-org (md)
   "Convert markdown MD to Org markup (the pure-elisp conversion tier).
@@ -1726,26 +1740,39 @@ MD."
          (t (push (pearl--md-line-to-org line) out))))
       (string-join (nreverse out) "\n"))))
 
+(defun pearl--org-emphasis-to-md (s)
+  "Convert Org links / bold / italic in S back to markdown.
+S must contain no verbatim ~code~ spans -- the caller splits those out so their
+contents stay literal.  Italics are word-bounded so paths and URLs are left
+alone."
+  ;; [[url][text]] -> [text](url)
+  (setq s (replace-regexp-in-string
+           "\\[\\[\\([^]]+\\)\\]\\[\\([^]]+\\)\\]\\]" "[\\2](\\1)" s))
+  ;; [[url]] -> url
+  (setq s (replace-regexp-in-string "\\[\\[\\([^]]+\\)\\]\\]" "\\1" s))
+  ;; *bold* -> **bold**
+  (setq s (replace-regexp-in-string "\\*\\([^*\n]+?\\)\\*" "**\\1**" s))
+  ;; /italic/ -> _italic_, word-bounded so /usr/local paths are left alone
+  (setq s (replace-regexp-in-string
+           "\\(^\\|[^[:alnum:]/]\\)/\\([^/\n]+?\\)/\\([^[:alnum:]/]\\|$\\)"
+           "\\1_\\2_\\3" s))
+  s)
+
 (defun pearl--org-line-to-md (line)
   "Convert inline Org markup in LINE back to markdown.
-The inverse of `pearl--md-line-to-org': org links, verbatim, bold, and
-italics become their markdown forms.  Other text passes through unchanged.
-Italics are word-bounded so filesystem paths and URLs are left alone."
-  (let ((s line))
-    ;; [[url][text]] -> [text](url)   (before verbatim/emphasis touch brackets)
-    (setq s (replace-regexp-in-string
-             "\\[\\[\\([^]]+\\)\\]\\[\\([^]]+\\)\\]\\]" "[\\2](\\1)" s))
-    ;; [[url]] -> url
-    (setq s (replace-regexp-in-string "\\[\\[\\([^]]+\\)\\]\\]" "\\1" s))
-    ;; ~code~ -> `code`
-    (setq s (replace-regexp-in-string "~\\([^~\n]+\\)~" "`\\1`" s))
-    ;; *bold* -> **bold**
-    (setq s (replace-regexp-in-string "\\*\\([^*\n]+?\\)\\*" "**\\1**" s))
-    ;; /italic/ -> _italic_, word-bounded so /usr/local paths are left alone
-    (setq s (replace-regexp-in-string
-             "\\(^\\|[^[:alnum:]/]\\)/\\([^/\n]+?\\)/\\([^[:alnum:]/]\\|$\\)"
-             "\\1_\\2_\\3" s))
-    s))
+The inverse of `pearl--md-line-to-org': org links, verbatim, bold, and italics
+become their markdown forms.  Verbatim ~code~ spans are tokenized first and
+their contents kept literal (symmetric with the md->org direction), so a code
+span containing markup round-trips exactly."
+  (let ((result "")
+        (pos 0))
+    (while (string-match "~\\([^~\n]+\\)~" line pos)
+      (setq result (concat result
+                           (pearl--org-emphasis-to-md
+                            (substring line pos (match-beginning 0)))
+                           "`" (match-string 1 line) "`"))
+      (setq pos (match-end 0)))
+    (concat result (pearl--org-emphasis-to-md (substring line pos)))))
 
 (defun pearl--org-to-md (org)
   "Convert Org markup ORG back to markdown (the push direction).