Patch 8.2.4103

[Bram Moolenaar]

Patch 8.2.4103
Problem: Vim9: variable declared in for loop not initialzed.
Solution: Always initialze the variable. (closes #9535)
Files: src/vim9instr.c, src/proto/vim9instr.pro, src/vim9compile.c,
src/testdir/test_vim9_assign.vim


*** ../vim-8.2.4102/src/vim9instr.c 2022-01-13 21:15:17.237958552 +0000
--- src/vim9instr.c 2022-01-15 21:27:51.386880879 +0000
***************
*** 1845,1850 ****
--- 1845,1869 ----
return FAIL;
}

+ /*
+ * Return TRUE when inside a "for" or "while" loop.
+ */
+ int
+ inside_loop_scope(cctx_T *cctx)
+ {
+ scope_T *scope = cctx->ctx_scope;
+
+ for (;;)
+ {
+ if (scope == NULL)
+ break;
+ if (scope->se_type == FOR_SCOPE || scope->se_type == WHILE_SCOPE)
+ return TRUE;
+ scope = scope->se_outer;
+ }
+ return FALSE;
+ }
+
int
generate_store_lhs(cctx_T *cctx, lhs_T *lhs, int instr_count, int is_decl)
{
***************
*** 1869,1876 ****
varnumber_T val = isn->isn_arg.number;
garray_T *stack = &cctx->ctx_type_stack;

! if (val == 0 && is_decl)
{
--instr->ga_len;
}
else
--- 1888,1896 ----
varnumber_T val = isn->isn_arg.number;
garray_T *stack = &cctx->ctx_type_stack;

! if (val == 0 && is_decl && !inside_loop_scope(cctx))
{
+ // zero is the default value, no need to do anything
--instr->ga_len;
}
else
*** ../vim-8.2.4102/src/proto/vim9instr.pro 2022-01-08 18:43:36.877446896 +0000
--- src/proto/vim9instr.pro 2022-01-15 21:28:22.982855994 +0000
***************
*** 63,68 ****
--- 63,69 ----
int generate_cmdmods(cctx_T *cctx, cmdmod_T *cmod);
int generate_undo_cmdmods(cctx_T *cctx);
int generate_store_var(cctx_T *cctx, assign_dest_T dest, int opt_flags, int vimvaridx, int scriptvar_idx, int scriptvar_sid, type_T *type, char_u *name);
+ int inside_loop_scope(cctx_T *cctx);
int generate_store_lhs(cctx_T *cctx, lhs_T *lhs, int instr_count, int is_decl);
void may_generate_prof_end(cctx_T *cctx, int prof_lnum);
void delete_instr(isn_T *isn);
*** ../vim-8.2.4102/src/vim9compile.c 2022-01-15 14:16:33.938539800 +0000
--- src/vim9compile.c 2022-01-15 21:33:22.102611149 +0000
***************
*** 2256,2267 ****
case VAR_VOID:
case VAR_INSTR:
case VAR_SPECIAL: // cannot happen
! // This is skipped for local variables, they are
! // always initialized to zero.
! if (lhs.lhs_dest == dest_local)
skip_store = TRUE;
else
generate_PUSHNR(cctx, 0);
break;
}
}
--- 2256,2272 ----
case VAR_VOID:
case VAR_INSTR:
case VAR_SPECIAL: // cannot happen
! // This is skipped for local variables, they are always
! // initialized to zero. But in a "for" or "while" loop
! // the value may have been changed.
! if (lhs.lhs_dest == dest_local
! && !inside_loop_scope(cctx))
skip_store = TRUE;
else
+ {
+ instr_count = instr->ga_len;
generate_PUSHNR(cctx, 0);
+ }
break;
}
}
*** ../vim-8.2.4102/src/testdir/test_vim9_assign.vim 2022-01-06 21:10:24.469027861 +0000
--- src/testdir/test_vim9_assign.vim 2022-01-15 21:36:49.642356047 +0000
***************
*** 587,592 ****
--- 587,627 ----
CheckDefFailure(lines, 'E1012: Type mismatch; expected list<number> but got dict<unknown>', 2)
enddef

+ def Test_init_in_for_loop()
+ var lines =<< trim END
+ var l: list<number> = []
+ for i in [3, 4]
+ var n: number
+ add(l, n)
+ n = 123
+ endfor
+ assert_equal([0, 0], l)
+ END
+ CheckDefAndScriptSuccess(lines)
+
+ lines =<< trim END
+ var l: list<number> = []
+ for i in [3, 4]
+ var n: number = 0
+ add(l, n)
+ n = 123
+ endfor
+ assert_equal([0, 0], l)
+ END
+ CheckDefAndScriptSuccess(lines)
+
+ lines =<< trim END
+ var l: list<number> = []
+ for i in [3, 4]
+ var n: number = 3
+ add(l, n)
+ n = 123
+ endfor
+ assert_equal([3, 3], l)
+ END
+ CheckDefAndScriptSuccess(lines)
+ enddef
+
def Test_extend_list()
var lines =<< trim END
var l1: list<number>
*** ../vim-8.2.4102/src/version.c 2022-01-15 21:08:11.899395839 +0000
--- src/version.c 2022-01-15 21:28:14.490862718 +0000
***************
*** 752,753 ****
--- 752,755 ----
{ /* Add new patch number below this line */
+ /**/
+ 4103,
/**/

--
"A mouse can be just as dangerous as a bullet or a bomb."
(US Representative Lamar Smith, R-Texas)

/// Bram Moolenaar -- Br...@Moolenaar.net -- http://www.Moolenaar.net \\\
/// \\\
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\\\ help me help AIDS victims -- http://ICCF-Holland.org ///