From 4ef8b374faba519b4fdde848c40f2127819126b8 Mon Sep 17 00:00:00 2001
From: metagn <metagngn@gmail.com>
Date: Sun, 18 May 2025 18:49:46 +0300
Subject: [PATCH] expand `OchoiceX` on resem

---
 src/nimony/sem.nim                            | 23 ++++++++++++++++++-
 src/nimony/sembasics.nim                      | 16 +++++++++++++
 tests/nimony/lookups/tcrossmoduleoverload.nim | 12 ++++++++++
 3 files changed, 50 insertions(+), 1 deletion(-)
 create mode 100644 tests/nimony/lookups/tcrossmoduleoverload.nim

diff --git a/src/nimony/sem.nim b/src/nimony/sem.nim
index 53d0a832e..35fabaf12 100644
--- a/src/nimony/sem.nim
+++ b/src/nimony/sem.nim
@@ -6763,6 +6763,27 @@ proc semTableConstructor(c: var SemContext; it: var Item; flags: set[SemFlag]) =
   it.typ = item.typ
   inc it.n
 
+proc expandSymChoice(c: var SemContext; n: var Cursor) =
+  let info = n.info
+  takeToken c, n
+  assert n.kind == Symbol
+  var name = pool.syms[n.symId]
+  extractBasename(name)
+  var marker = initHashSet[SymId]()
+  while n.kind != ParRi:
+    assert n.kind == Symbol
+    marker.incl n.symId
+    takeToken c, n
+  addSymChoiceSyms(c, pool.strings.getOrIncl(name), marker, info)
+  takeParRi c, n
+
+proc semSymChoice(c: var SemContext; it: var Item; flags: set[SemFlag] = {}) =
+  if it.n.exprKind == OchoiceX:
+    # could restrict to callees
+    expandSymChoice c, it.n
+  else:
+    takeTree c, it.n
+
 proc semExpr(c: var SemContext; it: var Item; flags: set[SemFlag] = {}) =
   case it.n.kind
   of IntLit:
@@ -7027,7 +7048,7 @@ proc semExpr(c: var SemContext; it: var Item; flags: set[SemFlag] = {}) =
     of FieldsX, FieldpairsX, InternalFieldPairsX:
       takeTree c, it.n
     of OchoiceX, CchoiceX:
-      takeTree c, it.n
+      semSymChoice c, it
     of HaddrX, HderefX:
       takeToken c, it.n
       # this is exactly what we need here as these operators have the same
diff --git a/src/nimony/sembasics.nim b/src/nimony/sembasics.nim
index 40bdf8625..aafbbccbb 100644
--- a/src/nimony/sembasics.nim
+++ b/src/nimony/sembasics.nim
@@ -130,6 +130,22 @@ proc buildSymChoice*(c: var SemContext; identifier: StrId; info: PackedLineInfo;
     c.dest.shrink oldLen
     c.dest.add identToken(identifier, info)
 
+proc addSymChoiceSyms*(c: var SemContext; identifier: StrId; marker: var HashSet[SymId]; info: PackedLineInfo) =
+  # like rawBuildSymChoice but adds to an existing symchoice, ignoring duplicates
+  var it = c.currentScope
+  while it != nil:
+    for sym in it.tab.getOrDefault(identifier):
+      if not marker.containsOrIncl(sym.name):
+        c.dest.addSymUse sym, info
+    it = it.up
+  # mirror considerImportedSymbols:
+  for moduleId in c.importTab.getOrDefault(identifier):
+    # prevent copies
+    let candidates = addr c.importedModules[moduleId].iface[identifier]
+    for defId in candidates[]:
+      if not marker.containsOrIncl(defId):
+        c.dest.add symToken(defId, info)
+
 proc isDeclared*(c: var SemContext; name: StrId): bool =
   var scope = c.currentScope
   while scope != nil:
diff --git a/tests/nimony/lookups/tcrossmoduleoverload.nim b/tests/nimony/lookups/tcrossmoduleoverload.nim
new file mode 100644
index 000000000..10711d249
--- /dev/null
+++ b/tests/nimony/lookups/tcrossmoduleoverload.nim
@@ -0,0 +1,12 @@
+import std / syncio
+
+type
+  MyS = distinct string
+
+proc write*(f: File; s: MyS) = write f, string(s)
+
+proc main =
+  var s90 = MyS"abc"
+  echo s90
+
+main()