new file mode 100644
--- /dev/null
+++ b/src/testdir/test_vim9_disassemble.vim
@@ -0,0 +1,220 @@
+" Test the :disassemble command, and compilation as a side effect
+
+func NotCompiled()
+  echo "not"
+endfunc
+
+let s:scriptvar = 4
+let g:globalvar = 'g'
+
+def s:ScriptFuncLoad(arg: string)
+  let local = 1
+  buffers
+  echo arg
+  echo local
+  echo v:version
+  echo s:scriptvar
+  echo g:globalvar
+  echo &tabstop
+  echo $ENVVAR
+  echo @z
+enddef
+
+def Test_disassembleLoad()
+  assert_fails('disass NoFunc', 'E1061:')
+  assert_fails('disass NotCompiled', 'E1062:')
+
+  let res = execute('disass s:ScriptFuncLoad')
+  assert_match('<SNR>\d*_ScriptFuncLoad.*'
+        \ .. 'buffers.*'
+        \ .. ' EXEC \+buffers.*'
+        \ .. ' LOAD arg\[-1\].*'
+        \ .. ' LOAD $0.*'
+        \ .. ' LOADV v:version.*'
+        \ .. ' LOADS s:scriptvar from .*test_vim9_disassemble.vim.*'
+        \ .. ' LOADG g:globalvar.*'
+        \ .. ' LOADENV $ENVVAR.*'
+        \ .. ' LOADREG @z.*'
+        \, res)
+enddef
+
+def s:ScriptFuncPush()
+  let localbool = true
+  let localspec = v:none
+  let localblob = 0z1234
+  if has('float')
+    let localfloat = 1.234
+  endif
+enddef
+
+def Test_disassemblePush()
+  let res = execute('disass s:ScriptFuncPush')
+  assert_match('<SNR>\d*_ScriptFuncPush.*'
+        \ .. 'localbool = true.*'
+        \ .. ' PUSH v:true.*'
+        \ .. 'localspec = v:none.*'
+        \ .. ' PUSH v:none.*'
+        \ .. 'localblob = 0z1234.*'
+        \ .. ' PUSHBLOB 0z1234.*'
+        \, res)
+  if has('float')
+  assert_match('<SNR>\d*_ScriptFuncPush.*'
+        \ .. 'localfloat = 1.234.*'
+        \ .. ' PUSHF 1.234.*'
+        \, res)
+  endif
+enddef
+
+def s:ScriptFuncStore()
+  let localnr = 1
+  localnr = 2
+  let localstr = 'abc'
+  localstr = 'xyz'
+  v:char = 'abc'
+  s:scriptvar = 'sv'
+  g:globalvar = 'gv'
+  &tabstop = 8
+  $ENVVAR = 'ev'
+  @z = 'rv'
+enddef
+
+def Test_disassembleStore()
+  let res = execute('disass s:ScriptFuncStore')
+  assert_match('<SNR>\d*_ScriptFuncStore.*'
+        \ .. 'localnr = 2.*'
+        \ .. ' STORE 2 in $0.*'
+        \ .. 'localstr = ''xyz''.*'
+        \ .. ' STORE $1.*'
+        \ .. 'v:char = ''abc''.*'
+        \ .. 'STOREV v:char.*'
+        \ .. 's:scriptvar = ''sv''.*'
+        \ .. ' STORES s:scriptvar in .*test_vim9_disassemble.vim.*'
+        \ .. 'g:globalvar = ''gv''.*'
+        \ .. ' STOREG g:globalvar.*'
+        \ .. '&tabstop = 8.*'
+        \ .. ' STOREOPT &tabstop.*'
+        \ .. '$ENVVAR = ''ev''.*'
+        \ .. ' STOREENV $ENVVAR.*'
+        \ .. '@z = ''rv''.*'
+        \ .. ' STOREREG @z.*'
+        \, res)
+enddef
+
+def s:ScriptFuncTry()
+  try
+    echo 'yes'
+  catch /fail/
+    echo 'no'
+  finally
+    echo 'end'
+  endtry
+enddef
+
+def Test_disassembleTry()
+  let res = execute('disass s:ScriptFuncTry')
+  assert_match('<SNR>\d*_ScriptFuncTry.*'
+        \ .. 'try.*'
+        \ .. 'TRY catch -> \d\+, finally -> \d\+.*'
+        \ .. 'catch /fail/.*'
+        \ .. ' JUMP -> \d\+.*'
+        \ .. ' PUSH v:exception.*'
+        \ .. ' PUSHS "fail".*'
+        \ .. ' COMPARESTRING =\~.*'
+        \ .. ' JUMP_IF_FALSE -> \d\+.*'
+        \ .. ' CATCH.*'
+        \ .. 'finally.*'
+        \ .. ' PUSHS "end".*'
+        \ .. 'endtry.*'
+        \ .. ' ENDTRY.*'
+        \, res)
+enddef
+
+def s:ScriptFuncNew()
+  let ll = [1, "two", 333]
+  let dd = #{one: 1, two: "val"}
+enddef
+
+def Test_disassembleNew()
+  let res = execute('disass s:ScriptFuncNew')
+  assert_match('<SNR>\d*_ScriptFuncNew.*'
+        \ .. 'let ll = \[1, "two", 333].*'
+        \ .. 'PUSHNR 1.*'
+        \ .. 'PUSHS "two".*'
+        \ .. 'PUSHNR 333.*'
+        \ .. 'NEWLIST size 3.*'
+        \ .. 'let dd = #{one: 1, two: "val"}.*'
+        \ .. 'PUSHS "one".*'
+        \ .. 'PUSHNR 1.*'
+        \ .. 'PUSHS "two".*'
+        \ .. 'PUSHS "val".*'
+        \ .. 'NEWDICT size 2.*'
+        \, res)
+enddef
+
+def FuncWithArg(arg)
+  echo arg
+enddef
+
+func UserFunc()
+  echo 'nothing'
+endfunc
+
+func UserFuncWithArg(arg)
+  echo a:arg
+endfunc
+
+def s:ScriptFuncCall(): string
+  changenr()
+  char2nr("abc")
+  Test_disassembleNew()
+  FuncWithArg(343)
+  ScriptFuncNew()
+  s:ScriptFuncNew()
+  UserFunc()
+  UserFuncWithArg("foo")
+  let FuncRef = function("UserFunc")
+  FuncRef()
+  let FuncRefWithArg = function("UserFuncWithArg")
+  FuncRefWithArg("bar")
+  return "yes"
+enddef
+
+def Test_disassembleCall()
+  let res = execute('disass s:ScriptFuncCall')
+  assert_match('<SNR>\d\+_ScriptFuncCall.*'
+        \ .. 'changenr().*'
+        \ .. ' BCALL changenr(argc 0).*'
+        \ .. 'char2nr("abc").*'
+        \ .. ' PUSHS "abc".*'
+        \ .. ' BCALL char2nr(argc 1).*'
+        \ .. 'Test_disassembleNew().*'
+        \ .. ' DCALL Test_disassembleNew(argc 0).*'
+        \ .. 'FuncWithArg(343).*'
+        \ .. ' PUSHNR 343.*'
+        \ .. ' DCALL FuncWithArg(argc 1).*'
+        \ .. 'ScriptFuncNew().*'
+        \ .. ' DCALL <SNR>\d\+_ScriptFuncNew(argc 0).*'
+        \ .. 's:ScriptFuncNew().*'
+        \ .. ' DCALL <SNR>\d\+_ScriptFuncNew(argc 0).*'
+        \ .. 'UserFunc().*'
+        \ .. ' UCALL UserFunc(argc 0).*'
+        \ .. 'UserFuncWithArg("foo").*'
+        \ .. ' PUSHS "foo".*'
+        \ .. ' UCALL UserFuncWithArg(argc 1).*'
+        \ .. 'let FuncRef = function("UserFunc").*'
+        \ .. 'FuncRef().*'
+        \ .. ' LOAD $\d.*'
+        \ .. ' PCALL (argc 0).*'
+        \ .. 'let FuncRefWithArg = function("UserFuncWithArg").*'
+        \ .. 'FuncRefWithArg("bar").*'
+        \ .. ' PUSHS "bar".*'
+        \ .. ' LOAD $\d.*'
+        \ .. ' PCALL (argc 1).*'
+        \ .. 'return "yes".*'
+        \ .. ' PUSHS "yes".*'
+        \ .. ' RETURN.*'
+        \, res)
+enddef
+
+
+" vim: ts=8 sw=2 sts=2 expandtab tw=80 fdm=marker