[erl-frontend] Add tests related to variables

Summary: Basic tests for variables and their assignments.

Reviewed By: mmarescotti

Differential Revision: D29964611

fbshipit-source-id: c22b3565c

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

@@ -59,3 +59,7 @@ codetoanalyze/erlang/features/src/tuples.erl, test_second_Bad/0, -24, NO_MATCHIN
 codetoanalyze/erlang/features/src/tuples.erl, test_third_Bad/0, -36, NO_MATCHING_FUNCTION_CLAUSE, no_bucket, ERROR, [calling context starts here,in call to `warn/1`,no matching function clause here]
 codetoanalyze/erlang/features/src/tuples.erl, third/1, 0, NO_MATCHING_FUNCTION_CLAUSE, no_bucket, ERROR, [*** LATENT ***,no matching function clause here]
 codetoanalyze/erlang/features/src/tuples.erl, warn/1, 0, NO_MATCHING_FUNCTION_CLAUSE, no_bucket, ERROR, [*** LATENT ***,no matching function clause here]
+codetoanalyze/erlang/features/src/variables.erl, test2_Bad/0, -13, NO_MATCHING_FUNCTION_CLAUSE, no_bucket, ERROR, [calling context starts here,in call to `warn/1`,no matching function clause here]
+codetoanalyze/erlang/features/src/variables.erl, test3_Bad/0, -24, NO_MATCHING_FUNCTION_CLAUSE, no_bucket, ERROR, [calling context starts here,in call to `warn/1`,no matching function clause here]
+codetoanalyze/erlang/features/src/variables.erl, test5_Bad/0, 2, NO_MATCH_OF_RHS, no_bucket, ERROR, [no match of RHS here]
+codetoanalyze/erlang/features/src/variables.erl, warn/1, 0, NO_MATCHING_FUNCTION_CLAUSE, no_bucket, ERROR, [*** LATENT ***,no matching function clause here]

infer/tests/codetoanalyze/erlang/features/src/variables.erl

@@ -0,0 +1,59 @@
+% Copyright (c) Facebook, Inc. and its affiliates.
+%
+% This source code is licensed under the MIT license found in the
+% LICENSE file in the root directory of this source tree.
+
+-module(variables).
+-export([
+    test1_Ok/0,
+    test2_Bad/0,
+    test3_Bad/0,
+    test4_Ok/0,
+    test5_Bad/0
+]).
+
+% Call this method with warn(1) to trigger a warning to expect
+warn(0) -> ok.
+
+test1_Ok() ->
+    X = 2,
+    Y = X,
+    Z = 3,
+    case Y of
+        2 -> ok
+    end,
+    case Z of
+        3 -> ok
+    end.
+
+test2_Bad() ->
+    X = 2,
+    Y = X,
+    Z = 3,
+    case Y of
+        2 -> warn(1)
+    end,
+    case Z of
+        3 -> ok
+    end.
+
+test3_Bad() ->
+    X = 2,
+    Y = X,
+    Z = 3,
+    case Y of
+        2 -> ok
+    end,
+    case Z of
+        3 -> warn(1)
+    end.
+
+test4_Ok() ->
+    X = 2,
+    2 = X,
+    ok.
+
+test5_Bad() ->
+    X = 2,
+    3 = X,
+    ok.