patch 8.2.2503: Vim9: a caught error may leave something on the stack

Problem:    Vim9: a caught error may leave something on the stack.
Solution:   Drop items from the stack if needed. (closes #7826)

diff --git a/src/testdir/test_vim9_script.vim b/src/testdir/test_vim9_script.vim
index 42a0d61dd0d59c3047165a9ead7c1854a68ebfdd..17b996f1768b150d816182da86818700c232be15 100644 (file)
--- a/src/testdir/test_vim9_script.vim
+++ b/src/testdir/test_vim9_script.vim
@@ -556,6 +556,16 @@ def Test_try_catch_throw()
     n = 411
   endtry
   assert_equal(411, n)
+
+  var counter = 0
+  for i in range(4)
+    try
+      eval [][0]
+    catch
+    endtry
+    counter += 1
+  endfor
+  assert_equal(4, counter)
 enddef
 
 def Test_cnext_works_in_catch()

diff --git a/src/version.c b/src/version.c
index ac9087a80908b2020e41174d83eee6a684262026..60f8a711d8e1fd297bd2b910ed2c21842b5f921f 100644 (file)
--- a/src/version.c
+++ b/src/version.c
@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2503,
 /**/
     2502,
 /**/

diff --git a/src/vim9execute.c b/src/vim9execute.c
index 6d462eaf1dbdc3baa9f16f6b36918709488ed1b4..8febf3623aa8baefd4cbe5db924c26843e40ccbd 100644 (file)
--- a/src/vim9execute.c
+++ b/src/vim9execute.c
@@ -24,7 +24,8 @@
 
 // Structure put on ec_trystack when ISN_TRY is encountered.
 typedef struct {
-    int            tcd_frame_idx;      // ec_frame_idx when ISN_TRY was encountered
+    int            tcd_frame_idx;      // ec_frame_idx at ISN_TRY
+    int            tcd_stack_len;      // size of ectx.ec_stack at ISN_TRY
     int            tcd_catch_idx;      // instruction of the first catch
     int            tcd_finally_idx;    // instruction of the finally block
     int            tcd_caught;         // catch block entered
@@ -2561,6 +2562,7 @@ call_def_function(
                    ++ectx.ec_trystack.ga_len;
                    ++trylevel;
                    trycmd->tcd_frame_idx = ectx.ec_frame_idx;
+                   trycmd->tcd_stack_len = ectx.ec_stack.ga_len;
                    trycmd->tcd_catch_idx = iptr->isn_arg.try.try_catch;
                    trycmd->tcd_finally_idx = iptr->isn_arg.try.try_finally;
                    trycmd->tcd_caught = FALSE;
@@ -2632,6 +2634,12 @@ call_def_function(
 
                        if (trycmd->tcd_return)
                            goto func_return;
+
+                       while (ectx.ec_stack.ga_len > trycmd->tcd_stack_len)
+                       {
+                           --ectx.ec_stack.ga_len;
+                           clear_tv(STACK_TV_BOT(0));
+                       }
                    }
                }
                break;