patch 9.1.0646: Vim9: imported function may not be found

Problem:  Vim9: imported function may not be found
Solution: Try to find the function by name (Ernie Rael)

fixes: #15381
closes: #15382

Signed-off-by: Ernie Rael <errael@raelity.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/testdir/test_vim9_builtin.vim

@@ -497,6 +497,56 @@ def Test_call_call()
   v9.CheckSourceDefAndScriptFailure(['call("reverse", [2], [1])'], ['E1013: Argument 3: type mismatch, expected dict<any> but got list<number>', 'E1206: Dictionary required for argument 3'])
 enddef
 
+def Test_call_imports()
+  # Use call with an imported function
+  var lines =<< trim END
+    vim9script
+
+    export const foo = 'foo'
+
+    export def Imported()
+    enddef
+
+    var count: number
+    export def ImportedListArg(l: list<number>)
+      count += 1
+      l[0] += count
+    enddef
+  END
+  writefile(lines, 'Test_call_imports_importme', 'D')
+  lines =<< trim END
+    vim9script
+    import './Test_call_imports_importme' as i_imp
+
+    var l = [12]
+    call('i_imp.ImportedListArg', [l])
+    assert_equal(13, l[0])
+    const ImportedListArg = i_imp.ImportedListArg
+    call('ImportedListArg', [l])
+    assert_equal(15, l[0])
+    const Imported = i_imp.Imported
+    call("Imported", [])
+
+    assert_equal('foo', i_imp.foo)
+    const foo = i_imp.foo
+    assert_equal('foo', foo)
+  END
+  v9.CheckSourceScriptSuccess(lines)
+
+  # A few error cases
+  lines =<< trim END
+    vim9script
+    import './Test_call_imports_importme' as i_imp
+    const Imported = i_imp.Imported
+    const foo = i_imp.foo
+
+    assert_fails('call("i_imp.foo", [])', 'E117:') # foo is not a function
+    assert_fails('call("foo", [])', 'E117:') # foo is not a function
+    assert_fails('call("i_xxx.foo", [])', 'E117:') # i_xxx not imported file
+  END
+  v9.CheckSourceScriptSuccess(lines)
+enddef
+
 def Test_ch_canread()
   if !has('channel')
     CheckFeature channel

src/userfunc.c

@@ -2211,6 +2211,48 @@ find_func_with_prefix(char_u *name, int sid)
     return NULL;
 }
 
+/*
+ * Find a function by name, return pointer to it.
+ * The name may be a local script variable, VAR_FUNC. or it may be a fully
+ * qualified import name such as 'i_imp.FuncName'.
+ *
+ * When VAR_FUNC, the import might either direct or autoload.
+ * When 'i_imp.FuncName' it is direct, autoload is rewritten as i_imp#FuncName
+ * in f_call and subsequently found.
+ */
+    static ufunc_T *
+find_func_imported(char_u *name, int flags)
+{
+    ufunc_T	*func = NULL;
+    char_u	*dot = name; // Find a dot, '.', in the name
+
+    // Either run into '.' or the end of the string
+    while (eval_isnamec(*dot))
+	++dot;
+
+    if (*dot == '.')
+    {
+	imported_T *import = find_imported(name, dot - name, FALSE);
+	if (import != NULL)
+	    func = find_func_with_sid(dot + 1, import->imp_sid);
+    }
+    else if (*dot == NUL) // looking at the entire string
+    {
+	hashtab_T *ht = get_script_local_ht();
+	if (ht != NULL)
+	{
+	    hashitem_T *hi = hash_find(ht, name);
+	    if (!HASHITEM_EMPTY(hi))
+	    {
+		dictitem_T *di = HI2DI(hi);
+		if (di->di_tv.v_type == VAR_FUNC)
+		    func = find_func_even_dead(di->di_tv.vval.v_string, flags);
+	    }
+	}
+    }
+    return func;
+}
+
 /*
  * Find a function by name, return pointer to it in ufuncs.
  * When "flags" has FFED_IS_GLOBAL don't find script-local or imported
@@ -2260,8 +2302,15 @@ find_func_even_dead(char_u *name, int flags)
     }
 
     // Find autoload function if this is an autoload script.
-    return find_func_with_prefix(name[0] == 's' && name[1] == ':'
+    func = find_func_with_prefix(name[0] == 's' && name[1] == ':'
 				       ? name + 2 : name, current_sctx.sc_sid);
+    if (func != NULL)
+	return func;
+
+    // Find a script-local "VAR_FUNC" or i_"imp.Func", so vim9script).
+    if (in_vim9script())
+	func = find_func_imported(name, flags);
+    return func;
 }
 
 /*

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    646,
 /**/
     645,
 /**/