fixes #19795; fixes #11852; fixes #19974; remove parsing pipeline, Nim now parses the whole module at one time (#21379)

* fixes #19795; remove parse pipeline

* isScript

* fixes nimscriptapi

* don't touch reorder

* check script

* fixes tests

* it seems implicit imports of system cause troubles

* access the first child of `nkStmtList`

* ignore comments

* minor messages

* perhaps increases hloLoopDetector

* the module is a stmtList, which changes the errors

* fixes nimdoc

* fixes tlinter

* fixes nim  secret tests

* fixes arc_misc

* fixes nim secret tests again

* safe; fixes one more test

* GlobalError is the root cause too

* fixes parsing errors

* put emit types to the cfsForwardTypes section

* fixes #11852; `{.push checks:off}` now works in procs

* disable navigator

* fixes nimdoc

* add tests for JS

* fixes nimsuggest

tests/overflow/toverflow.nim

@@ -0,0 +1,82 @@
+discard """
+  output: "ok"
+  matrix: "--overflowChecks:off; --overflowChecks:off --b:js"
+"""
+# Tests nim's ability to detect overflows
+
+{.push overflowChecks: on.}
+
+var
+  a = high(int)
+  b = -2
+  overflowDetected = false
+
+try:
+  echo(b - a)
+except OverflowDefect:
+  overflowDetected = true
+
+{.pop.} # overflow check
+
+doAssert(overflowDetected)
+
+block: # Overflow checks in a proc
+  var
+    a = high(int)
+    b = -2
+    overflowDetected = false
+
+  {.push overflowChecks: on.}
+  proc foo() =
+    let c = b - a
+  {.pop.}
+
+  try:
+    foo()
+  except OverflowDefect:
+    overflowDetected = true
+
+  doAssert(overflowDetected)
+
+block: # Overflow checks in a forward declared proc
+  var
+    a = high(int)
+    b = -2
+    overflowDetected = false
+
+  proc foo()
+
+  {.push overflowChecks: on.}
+  proc foo() =
+    let c = b - a
+  {.pop.}
+
+  try:
+    foo()
+  except OverflowDefect:
+    overflowDetected = true
+
+  doAssert(overflowDetected)
+
+block: # Overflow checks doesn't affect fwd declaration
+  var
+    a = high(int)
+    b = -2
+    overflowDetected = false
+
+  {.push overflowChecks: on.}
+  proc foo()
+  {.pop.}
+
+  proc foo() =
+    let c = b - a
+
+  try:
+    foo()
+  except OverflowDefect:
+    overflowDetected = true
+
+  doAssert(not overflowDetected)
+
+
+echo "ok"