1 files changed, 123 insertions, 0 deletions
diff --git a/packages/markdown-it-14.1.0/lib/rules_inline/emphasis.mjs b/packages/markdown-it-14.1.0/lib/rules_inline/emphasis.mjs
new file mode 100644
index 0000000..4e3b273
--- /dev/null
+++ b/packages/markdown-it-14.1.0/lib/rules_inline/emphasis.mjs
@@ -0,0 +1,123 @@
+// Process *this* and _that_
+//
+
+// Insert each marker as a separate text token, and add it to delimiter list
+//
+function emphasis_tokenize (state, silent) {
+  const start = state.pos
+  const marker = state.src.charCodeAt(start)
+
+  if (silent) { return false }
+
+  if (marker !== 0x5F /* _ */ && marker !== 0x2A /* * */) { return false }
+
+  const scanned = state.scanDelims(state.pos, marker === 0x2A)
+
+  for (let i = 0; i < scanned.length; i++) {
+    const token = state.push('text', '', 0)
+    token.content = String.fromCharCode(marker)
+
+    state.delimiters.push({
+      // Char code of the starting marker (number).
+      //
+      marker,
+
+      // Total length of these series of delimiters.
+      //
+      length: scanned.length,
+
+      // A position of the token this delimiter corresponds to.
+      //
+      token: state.tokens.length - 1,
+
+      // If this delimiter is matched as a valid opener, `end` will be
+      // equal to its position, otherwise it's `-1`.
+      //
+      end: -1,
+
+      // Boolean flags that determine if this delimiter could open or close
+      // an emphasis.
+      //
+      open: scanned.can_open,
+      close: scanned.can_close
+    })
+  }
+
+  state.pos += scanned.length
+
+  return true
+}
+
+function postProcess (state, delimiters) {
+  const max = delimiters.length
+
+  for (let i = max - 1; i >= 0; i--) {
+    const startDelim = delimiters[i]
+
+    if (startDelim.marker !== 0x5F/* _ */ && startDelim.marker !== 0x2A/* * */) {
+      continue
+    }
+
+    // Process only opening markers
+    if (startDelim.end === -1) {
+      continue
+    }
+
+    const endDelim = delimiters[startDelim.end]
+
+    // If the previous delimiter has the same marker and is adjacent to this one,
+    // merge those into one strong delimiter.
+    //
+    // `<em><em>whatever</em></em>` -> `<strong>whatever</strong>`
+    //
+    const isStrong = i > 0 &&
+               delimiters[i - 1].end === startDelim.end + 1 &&
+               // check that first two markers match and adjacent
+               delimiters[i - 1].marker === startDelim.marker &&
+               delimiters[i - 1].token === startDelim.token - 1 &&
+               // check that last two markers are adjacent (we can safely assume they match)
+               delimiters[startDelim.end + 1].token === endDelim.token + 1
+
+    const ch = String.fromCharCode(startDelim.marker)
+
+    const token_o   = state.tokens[startDelim.token]
+    token_o.type    = isStrong ? 'strong_open' : 'em_open'
+    token_o.tag     = isStrong ? 'strong' : 'em'
+    token_o.nesting = 1
+    token_o.markup  = isStrong ? ch + ch : ch
+    token_o.content = ''
+
+    const token_c   = state.tokens[endDelim.token]
+    token_c.type    = isStrong ? 'strong_close' : 'em_close'
+    token_c.tag     = isStrong ? 'strong' : 'em'
+    token_c.nesting = -1
+    token_c.markup  = isStrong ? ch + ch : ch
+    token_c.content = ''
+
+    if (isStrong) {
+      state.tokens[delimiters[i - 1].token].content = ''
+      state.tokens[delimiters[startDelim.end + 1].token].content = ''
+      i--
+    }
+  }
+}
+
+// Walk through delimiter list and replace text tokens with tags
+//
+function emphasis_post_process (state) {
+  const tokens_meta = state.tokens_meta
+  const max = state.tokens_meta.length
+
+  postProcess(state, state.delimiters)
+
+  for (let curr = 0; curr < max; curr++) {
+    if (tokens_meta[curr] && tokens_meta[curr].delimiters) {
+      postProcess(state, tokens_meta[curr].delimiters)
+    }
+  }
+}
+
+export default {
+  tokenize: emphasis_tokenize,
+  postProcess: emphasis_post_process
+}