backport to version 2.0: display raises pragma in proc types (#23026) (#23028)

This affects also nimsuggest hints (e.g. on mouse hover), as well as
compiler messages.

(cherry picked from commit 618ccb6)

Author: nickysn

compiler/types.nim

@@ -11,7 +11,7 @@
 
 import
   intsets, ast, astalgo, trees, msgs, strutils, platform, renderer, options,
-  lineinfos, int128, modulegraphs, astmsgs
+  lineinfos, int128, modulegraphs, astmsgs, wordrecg
 
 when defined(nimPreviewSlimSystem):
   import std/[assertions, formatfloat]
@@ -758,6 +758,14 @@ proc typeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
       result.add(')')
       if t.len > 0 and t[0] != nil: result.add(": " & typeToString(t[0]))
       var prag = if t.callConv == ccNimCall and tfExplicitCallConv notin t.flags: "" else: $t.callConv
+      if not isNil(t.owner) and not isNil(t.owner.ast) and (t.owner.ast.len - 1) >= pragmasPos:
+        let pragmasNode = t.owner.ast[pragmasPos]
+        let raisesSpec = effectSpec(pragmasNode, wRaises)
+        if not isNil(raisesSpec):
+          addSep(prag)
+          prag.add("raises: ")
+          prag.add($raisesSpec)
+
       if tfNoSideEffect in t.flags:
         addSep(prag)
         prag.add("noSideEffect")

tests/effects/teffects1.nim

@@ -39,7 +39,7 @@ proc foo(x: int): string {.nimcall, raises: [ValueError].} =
 
 var p: MyProcType = foo #[tt.Error
                     ^
-type mismatch: got <proc (x: int): string{.nimcall, noSideEffect, gcsafe.}> but expected 'MyProcType = proc (x: int): string{.closure.}'
+type mismatch: got <proc (x: int): string{.nimcall, raises: [ValueError], noSideEffect, gcsafe.}> but expected 'MyProcType = proc (x: int): string{.closure.}'
   Calling convention mismatch: got '{.nimcall.}', but expected '{.closure.}'.
 .raise effects differ
 ]#