Merge pull request #548 from xxdavid/fix_shortcurcuit_inference

Fix type inference for `andalso` & `orelse`
josefs · Aug 30, 2023 · cb6c1cf · cb6c1cf
2 parents 9d27389 + adc9de3
commit cb6c1cf
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Showing 2 changed files with 22 additions and 2 deletions.
diff --git a/src/typechecker.erl b/src/typechecker.erl
@@ -2257,8 +2257,8 @@ type_check_logic_op(Env, Op, Arg1, Arg2) ->
                 {true, Cs4} ->
                     Inferred =
                         case Op of
-                            'andalso' -> type(union, [Ty1, {atom, erl_anno:new(0), false}]);
-                            'orelse'  -> type(union, [Ty1, {atom, erl_anno:new(0), true}]);
+                            'andalso' -> type(union, [Ty2, {atom, erl_anno:new(0), false}]);
+                            'orelse'  -> type(union, [Ty2, {atom, erl_anno:new(0), true}]);
                             _         -> type(boolean)
                         end,
                     {normalize(Inferred, Env)

diff --git a/test/should_pass/shortcut_ops_pass.erl b/test/should_pass/shortcut_ops_pass.erl
@@ -38,6 +38,26 @@ orelse_infer2(B, N) -> B orelse N.
 -spec orelse_infer3(boolean(), boolean()) -> _.
 orelse_infer3(B, X) -> B orelse X.
 
+-spec andalso_infer_and_check1(boolean(), number()) -> false | number().
+andalso_infer_and_check1(B, N) ->
+    X = B andalso N,
+    X.
+
+-spec andalso_infer_and_check2(boolean(), false | number()) -> false | number().
+andalso_infer_and_check2(B, N) ->
+    X = B andalso N,
+    X.
+
+-spec orelse_infer_and_check1(boolean(), number()) -> true | number().
+orelse_infer_and_check1(B, N) ->
+    X = B orelse N,
+    X.
+
+-spec orelse_infer_and_check2(boolean(), true | number()) -> true | number().
+orelse_infer_and_check2(B, N) ->
+    X = B orelse N,
+    X.
+
 -spec is_false_number(false | number()) -> ok.
 is_false_number(_) -> ok.