fixed dot operator recursive loop & macro suggest (#16922)

* basic stability improvements; refs nimsuggest
* fixed dot operator recursive loop & macro suggest
* hacky fix for run away dot operator sem check

Committing this mostly to make the issue more clear. Perhaps get better
feedback.

* semExprWithType seems like a better place to check
* fixed error messages const case expressions
* Clean-up test
* stopped the dot operator madness

No longer get infinite recursion when seming broken code with a dot
operator macro like in jsffi.

Co-authored-by: Araq <rumpf_a@web.de>

tests/errmsgs/t10734.nim

@@ -2,13 +2,14 @@ discard """
   cmd: "nim check $file"
   errormsg: ""
   nimout: '''
-t10734.nim(18, 1) Error: invalid indentation
-t10734.nim(18, 6) Error: invalid indentation
-t10734.nim(19, 7) Error: expression expected, but found '[EOF]'
-t10734.nim(17, 5) Error: 'proc' is not a concrete type; for a callback without parameters use 'proc()'
-t10734.nim(18, 6) Error: undeclared identifier: 'p'
-t10734.nim(18, 6) Error: 'p' cannot be assigned to
-t10734.nim(16, 3) Hint: 'T' is declared but not used [XDeclaredButNotUsed]
+t10734.nim(19, 1) Error: invalid indentation
+t10734.nim(19, 6) Error: invalid indentation
+t10734.nim(20, 7) Error: expression expected, but found '[EOF]'
+t10734.nim(18, 5) Error: 'proc' is not a concrete type; for a callback without parameters use 'proc()'
+t10734.nim(19, 6) Error: undeclared identifier: 'p'
+t10734.nim(19, 6) Error: expression 'p' has no type (or is ambiguous)
+t10734.nim(19, 6) Error: 'p' cannot be assigned to
+t10734.nim(17, 3) Hint: 'T' is declared but not used [XDeclaredButNotUsed]
 '''
 """
 

tests/js/t11166.nim

@@ -1,4 +1,20 @@
+discard """
+  output: '''
+test1
+test2
+'''
+"""
+
 import jsffi
 
+type
+  C = object
+    props: int
+
+var c: C
+
 when compiles(c.props):
-  echo "test"
+  echo "test1"
+
+when not compiles(d.props):
+  echo "test2"