Commit: patch 9.0.2157: Vim9: incorrectly parses :def func definitions

[Christian Brabandt]

patch 9.0.2157: Vim9: incorrectly parses :def func definitions

Commit: https://github.com/vim/vim/commit/e4a450a87ba532cbfe1c4e97cac378eaafc3ae39
Author: Christian Brabandt <c...@256bit.org>
Date: Fri Dec 8 20:57:38 2023 +0100

patch 9.0.2157: Vim9: incorrectly parses :def func definitions

Problem: Vim9: incorrectly parses :def func definitions
Solution: check for more context when parsing function args

Signed-off-by: Christian Brabandt <c...@256bit.org>
Incorrectly parses def function definitions

Vim currently allows to define the following vim9 function:
def Func(f=
)
enddef

It currently thinks a Lambda is following the `=` but it doesn't check,
that there is actually an expression following. So when such a think is
encountered, remember that an expression should be following.

If no expression is coming in the next few lines, fail parsing the
function arguments, which will Vim no longer accept such a function.

Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/src/testdir/test_vim9_func.vim b/src/testdir/test_vim9_func.vim
index 47b23e85e..27585a904 100644
--- a/src/testdir/test_vim9_func.vim
+++ b/src/testdir/test_vim9_func.vim
@@ -861,6 +861,13 @@ def Test_func_with_comments()
END
v9.CheckScriptFailure(lines, 'E125:', 1)

+ lines =<< trim END
+ def Func(f=
+ )
+ enddef
+ END
+ v9.CheckScriptFailure(lines, 'E125:', 2)
+
lines =<< trim END
def Func(
arg: string# comment
diff --git a/src/userfunc.c b/src/userfunc.c
index 33e73a9a5..e2b1bc322 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -243,6 +243,7 @@ get_function_args(
int c;
int any_default = FALSE;
char_u *whitep = *argp;
+ int need_expr = FALSE;

if (newargs != NULL)
ga_init2(newargs, sizeof(char_u *), 3);
@@ -282,7 +283,7 @@ get_function_args(
semsg(_(e_invalid_argument_str), *argp);
goto err_ret;
}
- if (*p == endchar)
+ if (*p == endchar && !need_expr)
break;

if (p[0] == '.' && p[1] == '.' && p[2] == '.')
@@ -435,6 +436,8 @@ get_function_args(
if (ga_grow(default_args, 1) == FAIL)
goto err_ret;

+ if (need_expr)
+ need_expr = FALSE;
// trim trailing whitespace
while (p > expr && VIM_ISWHITE(p[-1]))
p--;
@@ -453,7 +456,11 @@ get_function_args(
}
}
else
+ {
mustend = TRUE;
+ if (*skipwhite(p) == NUL)
+ need_expr = TRUE;
+ }
}
else if (any_default)
{
diff --git a/src/version.c b/src/version.c
index f7d6cbcb6..919f42f2d 100644
--- a/src/version.c
+++ b/src/version.c
@@ -704,6 +704,8 @@ static char *(features[]) =

static int included_patches[] =
{ /* Add new patch number below this line */
+/**/
+ 2157,
/**/
2156,
/**/