Address review comment

Author: hvitved

rust/ql/lib/codeql/rust/internal/TypeInference.qll

@@ -2826,20 +2826,10 @@ private AssociatedTypeTypeParameter getFutureOutputTypeParameter() {
   result.getTypeAlias() = any(FutureTrait ft).getOutputType()
 }
 
-private predicate isReturnExprCfgAncestor(AstNode n) {
-  n instanceof ReturnExpr
-  or
-  exists(AstNode mid |
-    isReturnExprCfgAncestor(mid) and
-    n = mid.getParentNode() and
-    n.getEnclosingCfgScope() = mid.getEnclosingCfgScope()
-  )
-}
-
 pragma[nomagic]
 predicate isUnitBlockExpr(BlockExpr be) {
   not be.getStmtList().hasTailExpr() and
-  not isReturnExprCfgAncestor(be) and
+  not be = any(Callable c).getBody() and
   not be.hasLabel()
 }
 

rust/ql/test/library-tests/type-inference/main.rs

@@ -2865,7 +2865,7 @@ mod block_types {
 
     #[rustfmt::skip]
     fn f4(cond: bool) -> i32 {
-        let a = { // $ MISSING: certainType=a:()
+        let a = { // $ certainType=a:()
             if cond {
                 return 12;
             };

rust/ql/test/library-tests/type-inference/type-inference.expected

@@ -6476,15 +6476,19 @@ inferType
 | main.rs:2863:16:2863:16 | 0 |  | {EXTERNAL LOCATION} | i32 |
 | main.rs:2867:11:2867:14 | cond |  | {EXTERNAL LOCATION} | bool |
 | main.rs:2867:30:2875:5 | { ... } |  | {EXTERNAL LOCATION} | i32 |
+| main.rs:2868:13:2868:13 | a |  | file://:0:0:0:0 | () |
+| main.rs:2868:17:2872:9 | { ... } |  | file://:0:0:0:0 | () |
 | main.rs:2869:13:2871:13 | if cond {...} |  | file://:0:0:0:0 | () |
 | main.rs:2869:16:2869:19 | cond |  | {EXTERNAL LOCATION} | bool |
+| main.rs:2869:21:2871:13 | { ... } |  | file://:0:0:0:0 | () |
 | main.rs:2870:24:2870:25 | 12 |  | {EXTERNAL LOCATION} | i32 |
 | main.rs:2873:18:2873:26 | "a: {:?}\\n" |  | file://:0:0:0:0 | & |
 | main.rs:2873:18:2873:26 | "a: {:?}\\n" | &T | {EXTERNAL LOCATION} | str |
 | main.rs:2873:18:2873:29 | ...::_print(...) |  | file://:0:0:0:0 | () |
 | main.rs:2873:18:2873:29 | FormatArgsExpr |  | {EXTERNAL LOCATION} | Arguments |
 | main.rs:2873:18:2873:29 | MacroExpr |  | {EXTERNAL LOCATION} | Arguments |
 | main.rs:2873:18:2873:29 | { ... } |  | file://:0:0:0:0 | () |
+| main.rs:2873:29:2873:29 | a |  | file://:0:0:0:0 | () |
 | main.rs:2874:9:2874:9 | 0 |  | {EXTERNAL LOCATION} | i32 |
 | main.rs:2883:11:2918:1 | { ... } |  | file://:0:0:0:0 | () |
 | main.rs:2884:5:2884:21 | ...::f(...) |  | file://:0:0:0:0 | () |