patch 8.2.2206: :exe command line completion only works for first argument

Problem:    :exe command line completion only works for first argument.
Solution:   Skip over text if more is following. (closes #7546)
diff --git a/src/eval.c b/src/eval.c
index e4149ab..e612070 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -1904,6 +1904,24 @@
 	    while ((c = *++arg) != NUL && (c == ' ' || c == '\t'))
 		/* skip */ ;
     }
+
+    // ":exe one two" completes "two"
+    if ((cmdidx == CMD_execute
+		|| cmdidx == CMD_echo
+		|| cmdidx == CMD_echon
+		|| cmdidx == CMD_echomsg)
+	    && xp->xp_context == EXPAND_EXPRESSION)
+    {
+	for (;;)
+	{
+	    char_u *n = skiptowhite(arg);
+
+	    if (n == arg || IS_WHITE_OR_NUL(*skipwhite(n)))
+		break;
+	    arg = skipwhite(n);
+	}
+    }
+
     xp->xp_pattern = arg;
 }
 
diff --git a/src/testdir/test_cmdline.vim b/src/testdir/test_cmdline.vim
index 600a571..1c5cac7 100644
--- a/src/testdir/test_cmdline.vim
+++ b/src/testdir/test_cmdline.vim
@@ -673,6 +673,17 @@
   unlet $X_VIM_TEST_COMPLETE_ENV
 endfunc
 
+func Test_cmdline_complete_expression()
+  let g:SomeVar = 'blah'
+  for cmd in ['exe', 'echo', 'echon', 'echomsg']
+    call feedkeys(":" .. cmd .. " SomeV\<Tab>\<C-B>\"\<CR>", 'tx')
+    call assert_match('"' .. cmd .. ' SomeVar', @:)
+    call feedkeys(":" .. cmd .. " foo SomeV\<Tab>\<C-B>\"\<CR>", 'tx')
+    call assert_match('"' .. cmd .. ' foo SomeVar', @:)
+  endfor
+  unlet g:SomeVar
+endfunc
+
 " Test for various command-line completion
 func Test_cmdline_complete_various()
   " completion for a command starting with a comment
diff --git a/src/version.c b/src/version.c
index 5420862..adba2cd 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2206,
+/**/
     2205,
 /**/
     2204,