patch 9.0.0252: cursor in wrong place after virtual text

Problem:    Cursor in wrong place after virtual text.
Solution:   Do not change the length of a virtual text property.
            (closes #10964)

src/testdir/dumps/Test_prop_text_change_arg_1.dump

@@ -0,0 +1,5 @@
+>S+0&#ffffff0|e|t|E|r@1|o|r|C|o|d|e|(| |i+0&#ffd7ff255|d|:|-+0#4040ff13#ffffff0|1+0#0000000&|0|,| |i+0&#ffd7ff255|d|:|-+0#4040ff13#ffffff0|2+0#0000000&|0| |)| @29
+|s|e|c|o|n|d| |l|i|n|e| @48
+|~+0#4040ff13&| @58
+|~| @58
+| +0#0000000&@41|1|,|1| @10|A|l@1| 

src/testdir/dumps/Test_prop_text_change_arg_2.dump

@@ -0,0 +1,5 @@
+|S+0&#ffffff0|e|t|E|r@1|o|r|C|o|d|e|(| |i+0&#ffd7ff255|d|:|-+0#4040ff13#ffffff0|1+0#0000000&|2|3>4|,| |i+0&#ffd7ff255|d|:|-+0#4040ff13#ffffff0|2+0#0000000&|0| |)| @27
+|s|e|c|o|n|d| |l|i|n|e| @48
+|~+0#4040ff13&| @58
+|~| @58
+| +0#0000000&@41|1|,|1|8|-|2@1| @6|A|l@1| 

src/testdir/test_textprop.vim

@@ -3091,4 +3091,40 @@ func Test_insert_text_with_padding()
   call delete('XscriptPropsPadded')
 endfunc
 
+func Test_insert_text_change_arg()
+  CheckRunVimInTerminal
+
+  let lines =<< trim END
+      vim9script
+      setline(1, ['SetErrorCode( 10, 20 )', 'second line'])
+      prop_type_add('param', {highlight: 'DiffChange', start_incl: 1})
+      prop_type_add('padd', {highlight: 'NonText', start_incl: 1})
+      prop_add(1, 15, {
+          type: 'param',
+          text: 'id:',
+      })
+      prop_add(1, 15, {
+          type: 'padd',
+          text: '-',
+      })
+      prop_add(1, 19, {
+          type: 'param',
+          text: 'id:',
+      })
+      prop_add(1, 19, {
+          type: 'padd',
+          text: '-',
+      })
+  END
+  call writefile(lines, 'XscriptPropsChange')
+  let buf = RunVimInTerminal('-S XscriptPropsChange', #{rows: 5, cols: 60})
+  call VerifyScreenDump(buf, 'Test_prop_text_change_arg_1', {})
+
+  call term_sendkeys(buf, "ggf1cw1234\<Esc>")
+  call VerifyScreenDump(buf, 'Test_prop_text_change_arg_2', {})
+
+  call StopVimInTerminal(buf)
+  call delete('XscriptPropsChange')
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab

src/textprop.c

@@ -2127,7 +2127,8 @@ adjust_prop(
 	else
 	    prop->tp_col += added;
     }
-    else if (prop->tp_len > 0 && prop->tp_col + prop->tp_len > col)
+    else if (prop->tp_len > 0 && prop->tp_col + prop->tp_len > col
+	    && prop->tp_id >= 0)  // don't change length for virtual text
     {
 	int after = col - added - (prop->tp_col - 1 + prop->tp_len);
 

src/version.c

@@ -731,6 +731,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    252,
 /**/
     251,
 /**/