patch 9.1.0080: unexpected error for modifying final list using +=
Problem: unexpected error for modifying final list using += operator
(Ernie Rael)
Solution: Allow List value modification of a final variable using +=
operator
(Yegappan Lakshmanan)
fixes: #13745
fixes: #13959
closes: #13962
Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/doc/builtin.txt b/runtime/doc/builtin.txt
index 19b9bc9..062da08 100644
--- a/runtime/doc/builtin.txt
+++ b/runtime/doc/builtin.txt
@@ -2093,7 +2093,7 @@
Returns an empty List or String if {fromlist} and {tolist} are
identical.
- Examples:
+ Examples: >
:echo diff(['abc'], ['xxx'])
@@ -1 +1 @@
-abc
@@ -2103,7 +2103,7 @@
[{'from_idx': 0, 'from_count': 1, 'to_idx': 0, 'to_count': 1}]
:echo diff(readfile('oldfile'), readfile('newfile'))
:echo diff(getbufline(5, 1, '$'), getbufline(6, 1, '$'))
-
+<
For more examples, refer to |diff-func-examples|
Can also be used as a |method|: >
diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index 574b9c9..75ea2c7 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -1,4 +1,4 @@
-*eval.txt* For Vim version 9.1. Last change: 2024 Feb 05
+*eval.txt* For Vim version 9.1. Last change: 2024 Feb 06
VIM REFERENCE MANUAL by Bram Moolenaar
@@ -425,6 +425,18 @@
modified. The value must at least have the number of items in the range: >
:let list[3:5] = [3, 4, 5]
+To add items to a List in-place, you can use the |+=| operator: >
+ :let listA = [1, 2]
+ :let listA += [3, 4]
+<
+When two variables refer to the same List, changing one List in-place will
+cause the referenced List to be changed in-place: >
+ :let listA = [1, 2]
+ :let listB = listA
+ :let listB += [3, 4]
+ :echo listA
+ [1, 2, 3, 4]
+<
Adding and removing items from a list is done with functions. Here are a few
examples: >
:call insert(list, 'a') " prepend item 'a'
diff --git a/src/eval.c b/src/eval.c
index bf053df..fd44db6 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -1901,7 +1901,7 @@
&& !tv_check_lock(&di->di_tv, lp->ll_name, FALSE)))
&& tv_op(&tv, rettv, op) == OK)
set_var_const(lp->ll_name, lp->ll_sid, NULL, &tv, FALSE,
- ASSIGN_NO_DECL, 0);
+ ASSIGN_NO_DECL | ASSIGN_COMPOUND_OP, 0);
clear_tv(&tv);
}
}
diff --git a/src/evalvars.c b/src/evalvars.c
index cbcf2a7..0a84afd 100644
--- a/src/evalvars.c
+++ b/src/evalvars.c
@@ -3977,7 +3977,14 @@
if (check_typval_is_value(&di->di_tv) == FAIL)
goto failed;
- if (var_in_vim9script && (flags & ASSIGN_FOR_LOOP) == 0)
+ // List and Blob types can be modified in-place using the "+="
+ // compound operator. For other types, this is not allowed.
+ int type_inplace_modifiable =
+ (di->di_tv.v_type == VAR_LIST || di->di_tv.v_type == VAR_BLOB);
+
+ if (var_in_vim9script && (flags & ASSIGN_FOR_LOOP) == 0
+ && ((flags & ASSIGN_COMPOUND_OP) == 0
+ || !type_inplace_modifiable))
{
where_T where = WHERE_INIT;
svar_T *sv = find_typval_in_script(&di->di_tv, sid, TRUE);
@@ -3998,7 +4005,11 @@
}
}
- if ((flags & ASSIGN_FOR_LOOP) == 0
+ // Modifying a final variable with a List value using the "+="
+ // operator is allowed. For other types, it is not allowed.
+ if (((flags & ASSIGN_FOR_LOOP) == 0
+ && ((flags & ASSIGN_COMPOUND_OP) == 0
+ || !type_inplace_modifiable))
? var_check_permission(di, name) == FAIL
: var_check_ro(di->di_flags, name, FALSE))
goto failed;
diff --git a/src/testdir/test_vim9_assign.vim b/src/testdir/test_vim9_assign.vim
index aef09c5..4414f55 100644
--- a/src/testdir/test_vim9_assign.vim
+++ b/src/testdir/test_vim9_assign.vim
@@ -3484,4 +3484,101 @@
v9.CheckScriptFailure(lines, 'E1407: Cannot use a Typealias as a variable or value')
enddef
+" Test for modifying a final variable using a compound operator
+def Test_final_var_modification_with_compound_op()
+ var lines =<< trim END
+ vim9script
+
+ final i: number = 1000
+ assert_fails('i += 2', 'E46: Cannot change read-only variable "i"')
+ assert_fails('i -= 2', 'E46: Cannot change read-only variable "i"')
+ assert_fails('i *= 2', 'E46: Cannot change read-only variable "i"')
+ assert_fails('i /= 2', 'E46: Cannot change read-only variable "i"')
+ assert_fails('i %= 2', 'E46: Cannot change read-only variable "i"')
+ assert_equal(1000, i)
+
+ final f: float = 1000.0
+ assert_fails('f += 2', 'E46: Cannot change read-only variable "f"')
+ assert_fails('f -= 2', 'E46: Cannot change read-only variable "f"')
+ assert_fails('f *= 2', 'E46: Cannot change read-only variable "f"')
+ assert_fails('f /= 2', 'E46: Cannot change read-only variable "f"')
+ assert_equal(1000.0, f)
+
+ final s: string = 'abc'
+ assert_fails('s ..= "y"', 'E46: Cannot change read-only variable "s"')
+ assert_equal('abc', s)
+ END
+ v9.CheckScriptSuccess(lines)
+enddef
+
+" Test for modifying a final variable with a List value
+def Test_final_var_with_list_value()
+ var lines =<< trim END
+ vim9script
+
+ final listA: list<string> = []
+ var listB = listA
+
+ listB->add('a')
+ assert_true(listA is listB)
+ assert_equal(['a'], listA)
+ assert_equal(['a'], listB)
+
+ listB += ['b']
+ assert_true(listA is listB)
+ assert_equal(['a', 'b'], listA)
+ assert_equal(['a', 'b'], listB)
+
+ listA->add('c')
+ assert_true(listA is listB)
+ assert_equal(['a', 'b', 'c'], listA)
+ assert_equal(['a', 'b', 'c'], listB)
+
+ listA += ['d']
+ assert_true(listA is listB)
+ assert_equal(['a', 'b', 'c', 'd'], listA)
+ assert_equal(['a', 'b', 'c', 'd'], listB)
+ END
+ v9.CheckScriptSuccess(lines)
+enddef
+
+" Test for modifying a final variable with a List value using "+=" from a legacy
+" function.
+func Test_final_var_with_list_value_legacy()
+ vim9cmd final g:TestVar = ['a']
+ vim9cmd g:TestVar += ['b']
+ call assert_equal(['a', 'b'], g:TestVar)
+endfunc
+
+" Test for modifying a final variable with a Blob value
+def Test_final_var_with_blob_value()
+ var lines =<< trim END
+ vim9script
+
+ final blobA: blob = 0z10
+ var blobB = blobA
+
+ blobB->add(32)
+ assert_true(blobA is blobB)
+ assert_equal(0z1020, blobA)
+ assert_equal(0z1020, blobB)
+
+ blobB += 0z30
+ assert_true(blobA is blobB)
+ assert_equal(0z102030, blobA)
+ assert_equal(0z102030, blobB)
+
+ blobA->add(64)
+ assert_true(blobA is blobB)
+ assert_equal(0z10203040, blobA)
+ assert_equal(0z10203040, blobB)
+
+ blobA += 0z50
+ assert_true(blobA is blobB)
+ assert_equal(0z1020304050, blobA)
+ assert_equal(0z1020304050, blobB)
+ END
+ v9.CheckScriptSuccess(lines)
+enddef
+
" vim: ts=8 sw=2 sts=2 expandtab tw=80 fdm=marker
diff --git a/src/version.c b/src/version.c
index 3d99917..36f9dc0 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
static int included_patches[] =
{ /* Add new patch number below this line */
/**/
+ 80,
+/**/
79,
/**/
78,
diff --git a/src/vim.h b/src/vim.h
index fe23958..45cf8ca 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -2379,6 +2379,7 @@
#define ASSIGN_FOR_LOOP 0x40 // assigning to loop variable
#define ASSIGN_INIT 0x80 // not assigning a value, just a declaration
#define ASSIGN_UPDATE_BLOCK_ID 0x100 // update sav_block_id
+#define ASSIGN_COMPOUND_OP 0x200 // compound operator e.g. "+="
#include "ex_cmds.h" // Ex command defines
#include "spell.h" // spell checking stuff