From ff27a1697e26ec84f0d657b81ca09c3e081a8090 Mon Sep 17 00:00:00 2001
From: ychenfo <yc@m-labs.hk>
Date: Sun, 12 Dec 2021 05:39:48 +0800
Subject: [PATCH] nac3core: fix for loop type inference

---
 nac3core/src/typecheck/type_inferencer/mod.rs | 42 ++++++++++++++-----
 1 file changed, 31 insertions(+), 11 deletions(-)

diff --git a/nac3core/src/typecheck/type_inferencer/mod.rs b/nac3core/src/typecheck/type_inferencer/mod.rs
index 4ab40e614..c18bed890 100644
--- a/nac3core/src/typecheck/type_inferencer/mod.rs
+++ b/nac3core/src/typecheck/type_inferencer/mod.rs
@@ -122,9 +122,36 @@ impl<'a> fold::Fold<()> for Inferencer<'a> {
                     },
                 }
             }
-            ast::StmtKind::For { ref target, .. } => {
-                self.infer_pattern(target)?;
-                fold::fold_stmt(self, node)?
+            ast::StmtKind::For { target, iter, body, orelse, config_comment, type_comment } => {
+                self.infer_pattern(&target)?;
+                let target = self.fold_expr(*target)?;
+                let iter = self.fold_expr(*iter)?;
+                if self.unifier.unioned(iter.custom.unwrap(), self.primitives.range) {
+                    self.unify(self.primitives.int32, target.custom.unwrap(), &target.location)?;
+                } else {
+                    let list = self.unifier.add_ty(TypeEnum::TList { ty: target.custom.unwrap() });
+                    self.unify(list, iter.custom.unwrap(), &iter.location)?;
+                }
+                let body = body
+                    .into_iter()
+                    .map(|b| self.fold_stmt(b))
+                    .collect::<Result<Vec<_>, _>>()?;
+                let orelse = orelse
+                    .into_iter()
+                    .map(|o| self.fold_stmt(o))
+                    .collect::<Result<Vec<_>, _>>()?;
+                Located {
+                    location: node.location,
+                    node: ast::StmtKind::For {
+                        target: Box::new(target),
+                        iter: Box::new(iter),
+                        body,
+                        orelse,
+                        config_comment,
+                        type_comment,
+                    },
+                    custom: None
+                }
             }
             ast::StmtKind::Assign { ref mut targets, ref config_comment, .. } => {
                 for target in targets.iter_mut() {
@@ -201,14 +228,7 @@ impl<'a> fold::Fold<()> for Inferencer<'a> {
             _ => fold::fold_stmt(self, node)?,
         };
         match &stmt.node {
-            ast::StmtKind::For { target, iter, .. } => {
-                if self.unifier.unioned(iter.custom.unwrap(), self.primitives.range) {
-                    self.unify(self.primitives.int32, target.custom.unwrap(), &target.location)?;
-                } else {
-                    let list = self.unifier.add_ty(TypeEnum::TList { ty: target.custom.unwrap() });
-                    self.unify(list, iter.custom.unwrap(), &iter.location)?;
-                }
-            }
+            ast::StmtKind::For { .. } => {}
             ast::StmtKind::If { test, .. } | ast::StmtKind::While { test, .. } => {
                 self.unify(test.custom.unwrap(), self.primitives.bool, &test.location)?;
             }