encode less-than signs in text context after whitespace

Author: pjjw

lib/unsafe.js

@@ -109,6 +109,12 @@ export const unsafe = [
     inConstruct: 'phrasing',
     notInConstruct: fullPhrasingSpans
   },
+  {
+    character: '<',
+    before: '(?:[ \t\r\n]|$)',
+    inConstruct: 'phrasing',
+    notInConstruct: fullPhrasingSpans
+  },
   {character: '<', inConstruct: 'destinationLiteral'},
   // An equals to can start setext heading underlines.
   {atBreak: true, character: '='},

test/index.js

@@ -3932,6 +3932,26 @@ test('escape', async function (t) {
     )
   })
 
+  await t.test(
+    'should escape what would otherwise be html (2)',
+    async function () {
+      assert.equal(
+        to({type: 'paragraph', children: [{type: 'text', value: '<1%'}]}),
+        '\\<1%\n'
+      )
+    }
+  )
+
+  await t.test(
+    'dont escape a less-than sign that cant be a tag open',
+    async function () {
+      assert.equal(
+        to({type: 'paragraph', children: [{type: 'text', value: 'm<1%'}]}),
+        'm<1%\n'
+      )
+    }
+  )
+
   await t.test(
     'should escape what would otherwise be code (text)',
     async function () {