[erlang] More tests on matching against already bound variables

Summary: Add a test for simple "reassignment" and using the anonymus placeholder `_`.

Reviewed By: lisztspace

Differential Revision: D62126763

fbshipit-source-id: a8779efb7148a19db7e7fb1158fd68b1c9d15a70

infer/tests/codetoanalyze/erlang/compiler/issues.exp

@@ -661,7 +661,11 @@ nonmatch_match_expr:fn_test_match_func_arg_Bad/0: badmatch
 nonmatch_match_expr:fn_test_match_func_args_Bad/0: badmatch
 nonmatch_match_expr:fn_test_match_with_var_Bad/0: badmatch
 nonmatch_match_expr:fn_test_match_with_var_swapped_Bad/0: badmatch
+nonmatch_match_expr:fn_test_not_real_anon_match1_Bad/0: badmatch
+nonmatch_match_expr:fn_test_not_real_anon_match2_Bad/0: badmatch
+nonmatch_match_expr:fn_test_simple_match_Bad/0: badmatch
 nonmatch_match_expr:test_match_a_Ok/0: ok
+nonmatch_match_expr:test_match_anonymus_Ok/0: ok
 nonmatch_match_expr:test_match_b_Bad/0: badmatch
 nonmatch_match_expr:test_match_c_Ok/0: ok
 nonmatch_match_expr:test_match_d_Ok/0: ok

infer/tests/codetoanalyze/erlang/pulse/nonmatch/nonmatch_match_expr.erl

@@ -31,7 +31,11 @@
     test_match_with_var_Ok/0,
     fn_test_match_with_var_Bad/0,
     test_match_with_var_swapped_Ok/0,
-    fn_test_match_with_var_swapped_Bad/0
+    fn_test_match_with_var_swapped_Bad/0,
+    fn_test_simple_match_Bad/0,
+    test_match_anonymus_Ok/0,
+    fn_test_not_real_anon_match1_Bad/0,
+    fn_test_not_real_anon_match2_Bad/0
 ]).
 
 tail([_ | Xs]) -> Xs.
@@ -165,3 +169,21 @@ test_match_with_var_swapped_Ok() ->
 
 fn_test_match_with_var_swapped_Bad() ->
     crash_if_not_one_with_var_swapped(2).
+
+fn_test_simple_match_Bad() ->
+    A = 1,
+    A = 2.
+
+test_match_anonymus_Ok() ->
+    _ = 1,
+    _ = 2.
+
+fn_test_not_real_anon_match1_Bad() ->
+    % `_` is the only truly anonymus name
+    _A = 1,
+    _A = 2.
+
+fn_test_not_real_anon_match2_Bad() ->
+    % `_` is the only truly anonymus name
+    __ = 1,
+    __ = 2.