makes nimsuggest con work under v3 [Backport_1.6.18] (#23158)

Co-authored-by: Jake Leahy <jake@leahy.dev>

nimsuggest/nimsuggest.nim

@@ -957,10 +957,10 @@ proc executeNoHooksV3(cmd: IdeCmd, file: AbsoluteFile, dirtyfile: AbsoluteFile,
     graph.unmarkAllDirty()
 
   # these commands require partially compiled project
-  elif cmd in {ideSug, ideOutline, ideHighlight, ideDef, ideChkFile, ideType, ideDeclaration, ideExpand} and
-       (graph.needsCompilation(fileIndex) or cmd == ideSug):
+  elif cmd in {ideSug, ideCon, ideOutline, ideHighlight, ideDef, ideChkFile, ideType, ideDeclaration, ideExpand} and
+       (graph.needsCompilation(fileIndex) or cmd in {ideSug, ideCon}):
     # for ideSug use v2 implementation
-    if cmd == ideSug:
+    if cmd in {ideSug, ideCon}:
       conf.m.trackPos = newLineInfo(fileIndex, line, col)
       conf.m.trackPosAttached = false
     else:
@@ -1006,6 +1006,9 @@ proc executeNoHooksV3(cmd: IdeCmd, file: AbsoluteFile, dirtyfile: AbsoluteFile,
     # ideSug performs partial build of the file, thus mark it dirty for the
     # future calls.
     graph.markDirtyIfNeeded(file.string, fileIndex)
+  of ideCon:
+    graph.markDirty fileIndex
+    graph.markClientsDirty fileIndex
   of ideOutline:
     let n = parseFile(fileIndex, graph.cache, graph.config)
     graph.iterateOutlineNodes(n, graph.fileSymbols(fileIndex).deduplicateSymInfoPair)

nimsuggest/tests/tv3_con.nim

@@ -0,0 +1,13 @@
+# tests v3
+
+proc test(a: string, b:string) = discard
+proc test(a: int) = discard
+
+test(#[!]#
+
+discard """
+$nimsuggest --v3 --tester $file
+>con $1
+con;;skProc;;tv3_con.test;;proc (a: string, b: string);;$file;;3;;5;;"";;100
+con;;skProc;;tv3_con.test;;proc (a: int);;$file;;4;;5;;"";;100
+"""