[elpa] externals/js2-mode 394b85e 51/61: Add node creation and basic syntax tests

[Dmitry Gutov]

branch: externals/js2-mode
commit 394b85e0eb5b0a474c49c8ae24eff8ba912466d7
Author: babenhauserheide <arne.babenhauserheide@disy.net>
Commit: babenhauserheide <arne.babenhauserheide@disy.net>

    Add node creation and basic syntax tests
---
 js2-mode.el     | 19 ++++++++++++++-----
 tests/parser.el | 19 +++++++++++++++++++
 2 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/js2-mode.el b/js2-mode.el
index 304303e..341f01b 100644
--- a/js2-mode.el
+++ b/js2-mode.el
@@ -6096,10 +6096,10 @@ its relevant fields and puts it into `js2-ti-tokens'."
                           (?,
                            (throw 'return js2-COMMA))
                           (??
-                           (if (js2-match-char ?.)
-                               (throw 'return js2-OPTIONAL-CHAINING)
-                             (if (js2-match-char ??)
-                                 (throw 'return js2-NULLISH-COALESCING)
+                           (if (js2-match-char ??)
+                               (throw 'return js2-NULLISH-COALESCING)
+                             (if (js2-match-char ?.)
+                                 (throw 'return js2-OPTIONAL-CHAINING)
                                (throw 'return js2-HOOK))))
                           (?:
                            (if (js2-match-char ?:)
@@ -9938,7 +9938,7 @@ If NODE is non-nil, it is the AST node associated with 
the symbol."
 
 (defun js2-parse-cond-expr ()
   (let ((pos (js2-current-token-beg))
-        (pn (js2-parse-or-expr))
+        (pn (js2-parse-nullish-coalescing-expr))
         test-expr
         if-true
         if-false
@@ -10023,6 +10023,15 @@ FIXME: The latter option is unused?"
                                 'js2-parse-eq-expr)))
     pn))
 
+
+(defun js2-parse-nullish-coalescing-expr ()
+  (let ((pn (js2-parse-or-expr)))
+    (when (js2-match-token js2-NULLISH-COALESCING)
+      (setq pn (js2-make-binary js2-NULLISH-COALESCING
+                                pn
+                                'js2-parse-nullish-coalescing-expr)))
+    pn))
+
 (defconst js2-parse-eq-ops
   (list js2-EQ js2-NE js2-SHEQ js2-SHNE))
 
diff --git a/tests/parser.el b/tests/parser.el
index d890549..094ca29 100644
--- a/tests/parser.el
+++ b/tests/parser.el
@@ -17,6 +17,10 @@
 ;; You should have received a copy of the GNU General Public License
 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
 
+;;; Commentary:
+
+;; run tests with M-x ert-run-tests-interactively
+
 ;;; Code:
 
 (require 'ert)
@@ -1012,6 +1016,21 @@ the test."
     (should node)
     (should (string= (js2-node-text node) "99"))))
 
+;; nullish coalescing, via https://github.com/tc39/proposal-nullish-coalescing
+(js2-deftest nullish-coalescing-operator-null-variable
+  "var a = null; a ?? b;"
+  (js2-mode--and-parse)
+  (let ((node (js2-find-node js2-mode-ast 'js2-name-node-p)))
+    (should node)
+    (should (string= (js2-node-text node) "b"))))
+
+(js2-deftest nullish-coalescing-operator-null-value
+  "null ?? b;"
+  (js2-mode--and-parse)
+  (let ((node (js2-find-node js2-mode-ast 'js2-name-node-p)))
+    (should node)
+    (should (string= (js2-node-text node) "b"))))
+
 (js2-deftest unary-void-node-start
   "var c = void 0"
   (js2-mode--and-parse)