Improve whitespace and unary keyword parsing

* lisp/progmodes/js.el (js--name-start-chars): Remove, adding these
chars back to js--name-start-re.
(js--name-start-re): Add chars back from js--name-start-chars.

(js-jsx--tag-start-re): Improve regexp to capture the tag name (so it
can be disambiguated from a unary keyword), to match newlines (which
are common in this spot), and to require at least one whitespace
character before the attribute name.

(js-jsx--matched-tag-type): Ensure the “tag name” isn’t possibly a
unary keyword.

(js-jsx--self-closing-re, js-jsx--matching-close-tag-pos): Allow
whitespace around “<” and “>”.

* test/manual/indent/jsx-unclosed-2.jsx: Add tests for unary keyword
and whitespace parsing.

1 files changed, 16 insertions, 0 deletions

diff --git a/test/manual/indent/jsx-unclosed-2.jsx b/test/manual/indent/jsx-unclosed-2.jsx
index 9d80a2e9ae2..be0a605503f 100644
--- a/test/manual/indent/jsx-unclosed-2.jsx
+++ b/test/manual/indent/jsx-unclosed-2.jsx
@@ -19,6 +19,10 @@ if (foo > bar) void 0
 if (foo < await bar) void 0
 while (await foo > bar) void 0
 
+<div>
+  {foo < await bar}
+</div>
+
 // Allow unary keyword names as null-valued JSX attributes.
 // (As if this will EVER happen…)
 <Foo yield>
@@ -40,3 +44,15 @@ while (await foo > bar) void 0
 // “-” may be used in a JSXAttribute’s name.
 <Foo a-b-c=""
      x-y-z="" />
+
+// Weird spaces should be tolerated.
+< div >
+  < div >
+    < div
+      attr=""
+      / >
+    < div
+      attr=""
+      / >
+  < / div>
+< / div >