From 0d89d8ae89c861572496c5ae9683d986b28c957b Mon Sep 17 00:00:00 2001
From: Bram Moolenaar <Bram@vim.org>
Date: Sat, 31 Dec 2022 14:01:24 +0000
Subject: [PATCH] patch 9.0.1119: type of arguments not checked when calling a
 partial

Problem:    Type of arguments not checked when calling a partial.
Solution:   Give an error for a wrong argument type. (closes #11753)
---
 src/testdir/test_vim9_func.vim | 26 +++++++++++++++
 src/version.c                  |  2 ++
 src/vim9execute.c              | 61 +++++++++++++++++++++++-----------
 3 files changed, 69 insertions(+), 20 deletions(-)

diff --git a/src/testdir/test_vim9_func.vim b/src/testdir/test_vim9_func.vim
index 0edf7eab7..3840d1144 100644
--- a/src/testdir/test_vim9_func.vim
+++ b/src/testdir/test_vim9_func.vim
@@ -4277,6 +4277,32 @@ func Test_lambda_allocation_failure()
   bw!
 endfunc
 
+def Test_lambda_argument_type_check()
+  var lines =<< trim END
+      vim9script
+
+      def Scan(ll: list<any>): func(func(any))
+        return (Emit: func(any)) => {
+          for e in ll
+            Emit(e)
+          endfor
+        }
+      enddef
+
+      def Sum(Cont: func(func(any))): any
+        var sum = 0.0
+        Cont((v: float) => {  # <== NOTE: the lambda expects a float
+          sum += v
+        })
+        return sum
+      enddef
+
+      const ml = [3.0, 2, 7]
+      echo Scan(ml)->Sum()
+  END
+  v9.CheckScriptFailure(lines, 'E1013: Argument 1: type mismatch, expected float but got number')
+enddef
+
 def Test_multiple_funcref()
   # This was using a NULL pointer
   var lines =<< trim END
diff --git a/src/version.c b/src/version.c
index a66b58893..92c70ea99 100644
--- a/src/version.c
+++ b/src/version.c
@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1119,
 /**/
     1118,
 /**/
diff --git a/src/vim9execute.c b/src/vim9execute.c
index 06229b884..2bc81c38b 100644
--- a/src/vim9execute.c
+++ b/src/vim9execute.c
@@ -376,6 +376,41 @@ get_pt_outer(partial_T *pt)
     return &ptref->pt_outer;
 }
 
+/*
+ * Check "argcount" arguments on the stack against what "ufunc" expects.
+ * "off" is the offset of arguments on the stack.
+ * Return OK or FAIL.
+ */
+    static int
+check_ufunc_arg_types(ufunc_T *ufunc, int argcount, int off, ectx_T *ectx)
+{
+    if (ufunc->uf_arg_types != NULL || ufunc->uf_va_type != NULL)
+    {
+	typval_T	*argv = STACK_TV_BOT(0) - argcount - off;
+
+	// The function can change at runtime, check that the argument
+	// types are correct.
+	for (int i = 0; i < argcount; ++i)
+	{
+	    type_T *type = NULL;
+
+	    // assume a v:none argument, using the default value, is always OK
+	    if (argv[i].v_type == VAR_SPECIAL
+					 && argv[i].vval.v_number == VVAL_NONE)
+		continue;
+
+	    if (i < ufunc->uf_args.ga_len && ufunc->uf_arg_types != NULL)
+		type = ufunc->uf_arg_types[i];
+	    else if (ufunc->uf_va_type != NULL)
+		type = ufunc->uf_va_type->tt_member;
+	    if (type != NULL && check_typval_arg_type(type,
+					    &argv[i], NULL, i + 1) == FAIL)
+		return FAIL;
+	}
+    }
+    return OK;
+}
+
 /*
  * Call compiled function "cdf_idx" from compiled code.
  * This adds a stack frame and sets the instruction pointer to the start of the
@@ -498,6 +533,10 @@ call_dfunc(
 	return FAIL;
     }
 
+    // Check the argument types.
+    if (check_ufunc_arg_types(ufunc, argcount, vararg_count, ectx) == FAIL)
+	return FAIL;
+
     // Reserve space for:
     // - missing arguments
     // - stack frame
@@ -1345,26 +1384,8 @@ call_by_name(
 
     if (ufunc != NULL)
     {
-	if (ufunc->uf_arg_types != NULL || ufunc->uf_va_type != NULL)
-	{
-	    int i;
-	    typval_T	*argv = STACK_TV_BOT(0) - argcount;
-
-	    // The function can change at runtime, check that the argument
-	    // types are correct.
-	    for (i = 0; i < argcount; ++i)
-	    {
-		type_T *type = NULL;
-
-		if (i < ufunc->uf_args.ga_len && ufunc->uf_arg_types != NULL)
-		    type = ufunc->uf_arg_types[i];
-		else if (ufunc->uf_va_type != NULL)
-		    type = ufunc->uf_va_type->tt_member;
-		if (type != NULL && check_typval_arg_type(type,
-						&argv[i], NULL, i + 1) == FAIL)
-		    return FAIL;
-	    }
-	}
+	if (check_ufunc_arg_types(ufunc, argcount, 0, ectx) == FAIL)
+	    return FAIL;
 
 	return call_ufunc(ufunc, NULL, argcount, ectx, iptr, selfdict);
     }
-- 
2.40.0