fix(autocomplete): support slash commands after non-ASCII prefix and multiple slashes (#3924)

static/boot.js

@@ -1352,14 +1352,15 @@ $('msg').addEventListener('input',()=>{
     _saveComposerDraft(sid, $('msg').value, S.pendingFiles ? [...S.pendingFiles] : []);
   }
   const text=$('msg').value;
-  if(text.startsWith('/')&&text.indexOf('\n')===-1){
+  const _slashIdx=typeof _activeSlashCommandOffset==='function'?_activeSlashCommandOffset(text):-1;
+  if(_slashIdx>=0&&text.indexOf('\n')===-1){
     if(typeof getSlashAutocompleteMatches==='function'){
       getSlashAutocompleteMatches(text).then(matches=>{
         if(($('msg').value||'')!==text) return;
         if(matches.length)showCmdDropdown(matches); else hideCmdDropdown();
       });
     }else{
-      const prefix=text.slice(1);
+      const prefix=text.slice(_slashIdx+1);
       const matches=getMatchingCommands(prefix);
       if(matches.length)showCmdDropdown(matches); else hideCmdDropdown();
     }

static/commands.js

@@ -319,9 +319,32 @@ async function resolveBundleCommand(text,_meta){
   });
 }
 
+function _activeSlashCommandOffset(text){
+  // Find the offset of the slash that begins the active command token.
+  // A command token starts with / at the beginning of the line or after
+  // whitespace.  Excludes ~/ path tokens and mid-word slashes (URLs,
+  // provider/model IDs like openrouter/deepseek).
+  if(!text||text.indexOf('\n')!==-1) return -1;
+  // Scan for / at a token-initial position
+  for(let i=0;i<text.length;i++){
+    if(text[i]==='/'){
+      // Start of line = token-initial
+      if(i===0) return i;
+      // After whitespace = token-initial
+      if(/\s/.test(text[i-1])){
+        // Exclude ~/ path tokens
+        if(i+1<text.length&&text[i+1]==='~') continue;
+        return i;
+      }
+    }
+  }
+  return -1;
+}
+
 function _parseSlashAutocomplete(text){
-  if(!text.startsWith('/')||text.indexOf('\n')!==-1) return null;
-  const raw=text.slice(1);
+  const slashIdx=_activeSlashCommandOffset(text);
+  if(slashIdx<0) return null;
+  const raw=text.slice(slashIdx+1);
   const hasSpace=/\s/.test(raw);
   const parts=raw.split(/\s+/);
   const cmdName=(parts[0]||'').toLowerCase();
@@ -1621,7 +1644,7 @@ async function getBundleCommandMetadata(name){
 function refreshSlashCommandDropdown(){
   const ta=$('msg');if(!ta)return;
   const text=ta.value||'';
-  if(!text.startsWith('/')||text.indexOf('\n')!==-1){hideCmdDropdown();return;}
+  if(text.indexOf('\n')!==-1||_activeSlashCommandOffset(text)<0){hideCmdDropdown();return;}
   getSlashAutocompleteMatches(text).then(matches=>{
     if(($('msg').value||'')!==text) return;
     if(matches.length)showCmdDropdown(matches);else hideCmdDropdown();
@@ -1690,9 +1713,13 @@ function showCmdDropdown(matches){
         hideCmdDropdown();
         return;
       }
-      const nextValue=isSubArg?('/'+c.parent+' '+c.value):('/'+c.name+(c.arg?' ':''));
-      $('msg').value=nextValue;
-      $('msg').focus();
+      const _ta=$('msg');
+      const _cur=String(_ta&&_ta.value||'');
+      const _slashIdx=_activeSlashCommandOffset(_cur);
+      const _prefix=_slashIdx>=0?_cur.slice(0,_slashIdx):'';
+      const nextValue=_prefix+(isSubArg?('/'+c.parent+' '+c.value):('/'+c.name+(c.arg?' ':'')));
+      if(_ta)_ta.value=nextValue;
+      if(_ta)_ta.focus();
       if(!isSubArg&&c.source!=='skill'&&c.source!=='bundle'&&nextValue.endsWith(' ')&&typeof getSlashAutocompleteMatches==='function'){
         getSlashAutocompleteMatches(nextValue).then(matches=>{
           if(($('msg').value||'')!==nextValue) return;

tests/test_issue3924_cjk_slash_autocomplete.py

@@ -0,0 +1,134 @@
+"""Tests for #3924 — CJK text before / should not block slash autocomplete.
+
+The autocomplete trigger previously gated on text.startsWith('/') which
+fails when CJK (or any non-/ text) precedes the slash. The fix introduces
+_activeSlashCommandOffset() which finds the / at a token-initial position
+(start of line or after whitespace), excluding ~/ path tokens and mid-word
+slashes (URLs, provider/model IDs).
+"""
+import os
+import re
+
+
+_SRC = os.path.join(os.path.dirname(__file__), "..")
+
+
+def _read(name):
+    return open(os.path.join(_SRC, name), encoding="utf-8").read()
+
+
+class TestActiveSlashCommandOffset:
+    """_activeSlashCommandOffset must exist and use token-initial logic."""
+
+    def test_helper_exists(self):
+        js = _read("static/commands.js")
+        assert "function _activeSlashCommandOffset(text)" in js
+
+    def test_helper_checks_token_initial_position(self):
+        js = _read("static/commands.js")
+        m = re.search(
+            r'function _activeSlashCommandOffset\(text\)\{(.*?)\n\}',
+            js, re.DOTALL,
+        )
+        assert m, "_activeSlashCommandOffset not found"
+        fn = m.group(0)
+        # Must check for start-of-line (i===0) or after whitespace
+        assert "i===0" in fn or "i === 0" in fn, (
+            "_activeSlashCommandOffset must check start-of-line position"
+        )
+        assert "text[i-1]" in fn, (
+            "_activeSlashCommandOffset must check character before /"
+        )
+
+    def test_helper_excludes_path_tokens(self):
+        js = _read("static/commands.js")
+        m = re.search(
+            r'function _activeSlashCommandOffset\(text\)\{(.*?)\n\}',
+            js, re.DOTALL,
+        )
+        assert m
+        fn = m.group(0)
+        # Must exclude ~/ path tokens
+        assert "~" in fn, (
+            "_activeSlashCommandOffset must exclude ~/ path tokens"
+        )
+
+
+class TestParseSlashAutocompleteUsesHelper:
+    """_parseSlashAutocomplete must delegate to _activeSlashCommandOffset."""
+
+    def test_delegates_to_helper(self):
+        js = _read("static/commands.js")
+        m = re.search(
+            r'function _parseSlashAutocomplete\(text\)\{(.*?)\n\}',
+            js, re.DOTALL,
+        )
+        assert m, "_parseSlashAutocomplete not found"
+        fn = m.group(0)
+        assert "_activeSlashCommandOffset" in fn, (
+            "_parseSlashAutocomplete must use _activeSlashCommandOffset"
+        )
+
+    def test_does_not_use_startswith(self):
+        js = _read("static/commands.js")
+        m = re.search(
+            r'function _parseSlashAutocomplete\(text\)\{(.*?)\n\}',
+            js, re.DOTALL,
+        )
+        assert m
+        fn = m.group(0)
+        assert "startsWith('/')" not in fn, (
+            "_parseSlashAutocomplete must not gate on startsWith('/')"
+        )
+
+
+class TestRefreshSlashCommandDropdownUsesHelper:
+    """refreshSlashCommandDropdown must delegate to _activeSlashCommandOffset."""
+
+    def test_delegates_to_helper(self):
+        js = _read("static/commands.js")
+        m = re.search(
+            r'function refreshSlashCommandDropdown\(\)\{(.*?)\n\}',
+            js, re.DOTALL,
+        )
+        assert m, "refreshSlashCommandDropdown not found"
+        fn = m.group(0)
+        assert "_activeSlashCommandOffset" in fn, (
+            "refreshSlashCommandDropdown must use _activeSlashCommandOffset"
+        )
+
+
+class TestBootJsSlashTrigger:
+    """boot.js input handler must use _activeSlashCommandOffset."""
+
+    def test_boot_uses_helper(self):
+        js = _read("static/boot.js")
+        assert "_activeSlashCommandOffset" in js, (
+            "boot.js must use _activeSlashCommandOffset for the slash "
+            "autocomplete trigger (#3924)"
+        )
+
+    def test_boot_falls_back_to_path_autocomplete(self):
+        js = _read("static/boot.js")
+        # The path autocomplete else-if must still be present
+        assert "getComposerPathAutocompleteMatches" in js, (
+            "boot.js must preserve path autocomplete fallback"
+        )
+
+
+class TestSelectionHandlerPreservesPrefix:
+    """When an autocomplete item is selected, prefix text before the active
+    slash must be preserved rather than discarded."""
+
+    def test_selection_uses_helper(self):
+        js = _read("static/commands.js")
+        m = re.search(
+            r'function showCmdDropdown\(matches\)\{(.*?)\nfunction hideCmdDropdown',
+            js, re.DOTALL,
+        )
+        assert m, "showCmdDropdown not found"
+        fn = m.group(0)
+        assert "_activeSlashCommandOffset" in fn, (
+            "showCmdDropdown selection handler must use _activeSlashCommandOffset "
+            "to preserve prefix text before the slash (#3924)"
+        )