feat: Support nested TOML tables

kaushalmodi · Apr 29, 2022 · a1f434f · a1f434f
1 parent 65653d5
commit a1f434f
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Showing 3 changed files with 53 additions and 10 deletions.
diff --git a/README.org b/README.org
@@ -18,7 +18,7 @@ the Emacs core library [[https://git.savannah.gnu.org/cgit/emacs.git/tree/lisp/j
 
 It will then be gradually refactored so that it meets the
 specification defined below.
-* Library Completion Status [4/7]
+* Library Completion Status [5/7]
 - [X] Scalar
   - [X] Boolean
   - [X] Integer
@@ -29,9 +29,9 @@ specification defined below.
 - [X] Nil
 - [X] Arrays
 - [X] Array of Arrays
-- [-] Tables
+- [X] Tables
   - [X] Basic Tables
-  - [ ] Nested Tables
+  - [X] Nested Tables
 - [ ] Array of Tables
   - [ ] Basic Array of Tables
   - [ ] Nested Array of Tables
@@ -436,7 +436,8 @@ CLOSED: [2022-04-29 Fri 13:41]
   }
 }
 #+end_example
-*** Nested TOML Tables
+*** DONE Nested TOML Tables
+CLOSED: [2022-04-29 Fri 14:30]
 **** S-expression
 #+begin_src emacs-lisp :eval no :noweb-ref nested-tables
 '((table-1 . ((table-1a . ((key1 . "some string")
@@ -445,6 +446,12 @@ CLOSED: [2022-04-29 Fri 13:41]
                            (key2 . 98765))))))
 #+end_src
 **** TOML
+#+begin_src emacs-lisp :noweb yes :exports results :wrap src toml
+(tomelr-encode
+  <<nested-tables>>)
+#+end_src
+
+#+RESULTS:
 #+begin_src toml
 [table-1]
   [table-1.table-1a]

diff --git a/test/ttable.el b/test/ttable.el
@@ -41,5 +41,23 @@
       (push (tomelr-encode el) out))
     (should (equal ref (nreverse out)))))
 
+;;;; Nested tables
+(ert-deftest test-nested-table ()
+  (let ((inp '(((table-1 . ((table-1a . ((key1 . "some string")
+                                         (key2 . 123)))
+                            (table-1b . ((key1 . "foo")
+                                         (key2 . 98765))))))))
+        (ref '("[table-1]
+  [table-1.table-1a]
+    key1 = \"some string\"
+    key2 = 123
+  [table-1.table-1b]
+    key1 = \"foo\"
+    key2 = 98765"))
+        out)
+    (dolist (el inp)
+      (push (tomelr-encode el) out))
+    (should (equal ref (nreverse out)))))
+
 
 (provide 'ttable)
diff --git a/tomelr.el b/tomelr.el
@@ -52,6 +52,9 @@ ordered alphabetically.")
   "Current indentation level during encoding.
 Dictates repetitions of `tomelr-encoding-default-indentation'.")
 
+(defvar tomelr--print-table-hierarchy ()
+  "Internal variable used to save the TOML table hierarchy.")
+
 (defvar tomelr--print-keyval-separator " = "
   "String used to separate key-value pairs during encoding.")
 
@@ -211,12 +214,27 @@ Return nil if OBJECT cannot be encoded as a TOML string."
          ;; (message "[tomelr--print-stringlike DBG] %S is keyword" object)
          (tomelr--print-string (symbol-name object) 1))
         ((symbolp object)
-         ;; (message "[tomelr--print-stringlike DBG] %S is symbol" object)
-         (cond
-          ((equal type 'table)
-           (princ (format "[%s]" (symbol-name object))))
-          (t
-           (princ (symbol-name object)))))))
+         (let ((sym-name (symbol-name object)))
+           ;; (message "[tomelr--print-stringlike DBG] %S is symbol, type = %S, depth = %d"
+           ;;          object type tomelr--print-indentation-depth)
+           (cond
+            ((equal type 'table)
+             (if (null (nth tomelr--print-indentation-depth tomelr--print-table-hierarchy))
+                 (progn
+                   (push sym-name tomelr--print-table-hierarchy)
+                   (setq tomelr--print-table-hierarchy (nreverse tomelr--print-table-hierarchy)))
+               ;; Throw away table keys collected at higher depths, if
+               ;; any, from earlier runs of this function.
+               (setq tomelr--print-table-hierarchy
+                     (seq-take tomelr--print-table-hierarchy
+                               (1+ tomelr--print-indentation-depth)))
+               (setf (nth tomelr--print-indentation-depth tomelr--print-table-hierarchy)
+                     sym-name))
+             ;; (message "[tomelr--print-stringlike DBG] table hier: %S"
+             ;;          tomelr--print-table-hierarchy)
+             (princ (format "[%s]" (string-join tomelr--print-table-hierarchy "."))))
+            (t
+             (princ sym-name)))))))
 
 (defun tomelr--print-key (key &optional type)
   "Insert a TOML key representation of KEY at point.