Rust: Add type inference regression test

Author: hvitved

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

@@ -287,3 +287,44 @@ mod default_type_args {
         }
     }
 }
+
+mod from_default {
+    #[derive(Default)]
+    struct S;
+
+    fn f() -> S {
+        let x = Default::default(); // $ target=default type=x:S
+        From::from(x) // $ target=from
+    }
+
+    struct S1;
+
+    struct S2;
+
+    impl From<S> for S1 {
+        // from1
+        fn from(_: S) -> Self {
+            S1
+        }
+    }
+
+    impl From<S2> for S1 {
+        // from2
+        fn from(_: S2) -> Self {
+            S1
+        }
+    }
+
+    impl From<S> for S2 {
+        // from3
+        fn from(_: S) -> Self {
+            S2
+        }
+    }
+
+    fn g(b: bool) -> S1 {
+        let s = if b { S } else { Default::default() }; // $ target=default type=s:S
+        let x = From::from(s); // $ target=from1 type=x:S1
+        x
+    }
+}

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

@@ -3902,6 +3902,16 @@ inferCertainType
 | overloading.rs:281:21:281:47 | ...::f(...) |  | {EXTERNAL LOCATION} | i64 |
 | overloading.rs:282:17:282:17 | x |  | {EXTERNAL LOCATION} | i64 |
 | overloading.rs:282:21:282:61 | ...::f(...) |  | {EXTERNAL LOCATION} | i64 |
+| overloading.rs:295:17:298:5 | { ... } |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:306:17:306:17 | _ |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:306:31:308:9 | { ... } |  | overloading.rs:300:5:300:14 | S1 |
+| overloading.rs:313:17:313:17 | _ |  | overloading.rs:302:5:302:14 | S2 |
+| overloading.rs:313:32:315:9 | { ... } |  | overloading.rs:300:5:300:14 | S1 |
+| overloading.rs:320:17:320:17 | _ |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:320:31:322:9 | { ... } |  | overloading.rs:302:5:302:14 | S2 |
+| overloading.rs:325:10:325:10 | b |  | {EXTERNAL LOCATION} | bool |
+| overloading.rs:325:25:329:5 | { ... } |  | overloading.rs:300:5:300:14 | S1 |
+| overloading.rs:326:20:326:20 | b |  | {EXTERNAL LOCATION} | bool |
 | pattern_matching.rs:13:26:133:1 | { ... } |  | {EXTERNAL LOCATION} | Option |
 | pattern_matching.rs:13:26:133:1 | { ... } | T | {EXTERNAL LOCATION} | () |
 | pattern_matching.rs:15:5:18:5 | if ... {...} |  | {EXTERNAL LOCATION} | () |
@@ -12309,6 +12319,33 @@ inferType
 | overloading.rs:286:13:286:16 | S(...) | T | {EXTERNAL LOCATION} | i32 |
 | overloading.rs:286:13:286:16 | S(...) | T | {EXTERNAL LOCATION} | i64 |
 | overloading.rs:286:15:286:15 | 0 |  | {EXTERNAL LOCATION} | i32 |
+| overloading.rs:295:17:298:5 | { ... } |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:296:13:296:13 | x |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:296:17:296:34 | ...::default(...) |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:297:9:297:21 | ...::from(...) |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:297:20:297:20 | x |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:306:17:306:17 | _ |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:306:31:308:9 | { ... } |  | overloading.rs:300:5:300:14 | S1 |
+| overloading.rs:307:13:307:14 | S1 |  | overloading.rs:300:5:300:14 | S1 |
+| overloading.rs:313:17:313:17 | _ |  | overloading.rs:302:5:302:14 | S2 |
+| overloading.rs:313:32:315:9 | { ... } |  | overloading.rs:300:5:300:14 | S1 |
+| overloading.rs:314:13:314:14 | S1 |  | overloading.rs:300:5:300:14 | S1 |
+| overloading.rs:320:17:320:17 | _ |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:320:31:322:9 | { ... } |  | overloading.rs:302:5:302:14 | S2 |
+| overloading.rs:321:13:321:14 | S2 |  | overloading.rs:302:5:302:14 | S2 |
+| overloading.rs:325:10:325:10 | b |  | {EXTERNAL LOCATION} | bool |
+| overloading.rs:325:25:329:5 | { ... } |  | overloading.rs:300:5:300:14 | S1 |
+| overloading.rs:326:13:326:13 | s |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:326:17:326:54 | if b {...} else {...} |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:326:20:326:20 | b |  | {EXTERNAL LOCATION} | bool |
+| overloading.rs:326:22:326:26 | { ... } |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:326:24:326:24 | S |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:326:33:326:54 | { ... } |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:326:35:326:52 | ...::default(...) |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:327:13:327:13 | x |  | overloading.rs:300:5:300:14 | S1 |
+| overloading.rs:327:17:327:29 | ...::from(...) |  | overloading.rs:300:5:300:14 | S1 |
+| overloading.rs:327:28:327:28 | s |  | overloading.rs:292:5:293:13 | S |
+| overloading.rs:328:9:328:9 | x |  | overloading.rs:300:5:300:14 | S1 |
 | pattern_matching.rs:13:26:133:1 | { ... } |  | {EXTERNAL LOCATION} | Option |
 | pattern_matching.rs:13:26:133:1 | { ... } | T | {EXTERNAL LOCATION} | () |
 | pattern_matching.rs:14:9:14:13 | value |  | {EXTERNAL LOCATION} | Option |