simplify logic in scanDelims

fix https://github.com/markdown-it/markdown-it/issues/1003

lib/rules_inline/state_inline.mjs

@@ -86,9 +86,6 @@ StateInline.prototype.push = function (type, tag, nesting) {
 //  - canSplitWord - determine if these markers can be found inside a word
 //
 StateInline.prototype.scanDelims = function (start, canSplitWord) {
-  let can_open, can_close
-  let left_flanking = true
-  let right_flanking = true
   const max = this.posMax
   const marker = this.src.charCodeAt(start)
 
@@ -109,29 +106,13 @@ StateInline.prototype.scanDelims = function (start, canSplitWord) {
   const isLastWhiteSpace = isWhiteSpace(lastChar)
   const isNextWhiteSpace = isWhiteSpace(nextChar)
 
-  if (isNextWhiteSpace) {
+  const left_flanking =
-    left_flanking = false
+    !isNextWhiteSpace && (!isNextPunctChar || isLastWhiteSpace || isLastPunctChar)
-  } else if (isNextPunctChar) {
+  const right_flanking =
-    if (!(isLastWhiteSpace || isLastPunctChar)) {
+    !isLastWhiteSpace && (!isLastPunctChar || isNextWhiteSpace || isNextPunctChar)
-      left_flanking = false
-    }
-  }
-
-  if (isLastWhiteSpace) {
-    right_flanking = false
-  } else if (isLastPunctChar) {
-    if (!(isNextWhiteSpace || isNextPunctChar)) {
-      right_flanking = false
-    }
-  }
 
-  if (!canSplitWord) {
+  const can_open  = left_flanking  && (canSplitWord || !right_flanking || isLastPunctChar)
-    can_open  = left_flanking  && (!right_flanking || isLastPunctChar)
+  const can_close = right_flanking && (canSplitWord || !left_flanking  || isNextPunctChar)
-    can_close = right_flanking && (!left_flanking  || isNextPunctChar)
-  } else {
-    can_open  = left_flanking
-    can_close = right_flanking
-  }
 
   return { can_open, can_close, length: count }
 }