From 5093fe4614cab7e7594e4afeaa20162986b23bfd Mon Sep 17 00:00:00 2001
From: Akos Hajdu <akoshajdu@fb.com>
Date: Tue, 6 Jul 2021 06:05:30 -0700
Subject: [PATCH] [erl-frontend] Add tests for non-exhaistive case expressions

Summary: Add some test cases to potentially non-exhaustive case clauses.

Reviewed By: rgrig

Differential Revision: D29555525

fbshipit-source-id: f710e93e6
---
 .../codetoanalyze/erlang/nonmatch/issues.exp  |  6 +++-
 .../erlang/nonmatch/src/nonmatch.erl          | 33 ++++++++++++++++++-
 2 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/infer/tests/codetoanalyze/erlang/nonmatch/issues.exp b/infer/tests/codetoanalyze/erlang/nonmatch/issues.exp
index 0190973b2..b44bc2b53 100644
--- a/infer/tests/codetoanalyze/erlang/nonmatch/issues.exp
+++ b/infer/tests/codetoanalyze/erlang/nonmatch/issues.exp
@@ -1,5 +1,8 @@
 codetoanalyze/erlang/nonmatch/src/nonmatch.erl, assert_empty/1, 0, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [*** LATENT ***,no pattern match here]
 codetoanalyze/erlang/nonmatch/src/nonmatch.erl, assert_second_is_nil/1, 0, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [*** LATENT ***,no pattern match here]
+codetoanalyze/erlang/nonmatch/src/nonmatch.erl, case_simple/1, 1, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [*** LATENT ***,no pattern match here]
+codetoanalyze/erlang/nonmatch/src/nonmatch.erl, case_test_simple3_Bad/0, -14, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [calling context starts here,in call to `case_simple/1`,no pattern match here]
+codetoanalyze/erlang/nonmatch/src/nonmatch.erl, case_test_tail3_Bad/0, -15, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [calling context starts here,in call to `tail_with_case/1`,no pattern match here]
 codetoanalyze/erlang/nonmatch/src/nonmatch.erl, fp_list_match_test_secondnil1_Ok/0, -17, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [calling context starts here,in call to `assert_second_is_nil/1`,no pattern match here]
 codetoanalyze/erlang/nonmatch/src/nonmatch.erl, fp_list_match_test_secondnil2_Ok/0, -20, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [calling context starts here,in call to `assert_second_is_nil/1`,no pattern match here]
 codetoanalyze/erlang/nonmatch/src/nonmatch.erl, fp_match_test_c_Ok/0, 1, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [no pattern match here]
@@ -11,6 +14,7 @@ codetoanalyze/erlang/nonmatch/src/nonmatch.erl, list_match_test_tail3_Bad/0, -8,
 codetoanalyze/erlang/nonmatch/src/nonmatch.erl, match_test_b_Bad/0, 1, CONSTANT_ADDRESS_DEREFERENCE, no_bucket, WARNING, [in call to `two/0`,is the constant 2,assigned,returned,return from call to `two/0`,invalid access occurs here]
 codetoanalyze/erlang/nonmatch/src/nonmatch.erl, match_test_b_Bad/0, 1, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [no pattern match here]
 codetoanalyze/erlang/nonmatch/src/nonmatch.erl, match_test_e_Bad/0, -42, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [calling context starts here,in call to `tail/1`,no pattern match here]
-codetoanalyze/erlang/nonmatch/src/nonmatch.erl, match_test_g_Bad/0, 7, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [calling context starts here,in call to `only_accepts_one/1`,no pattern match here]
+codetoanalyze/erlang/nonmatch/src/nonmatch.erl, match_test_g_Bad/0, 32, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [calling context starts here,in call to `only_accepts_one/1`,no pattern match here]
 codetoanalyze/erlang/nonmatch/src/nonmatch.erl, only_accepts_one/1, 0, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [*** LATENT ***,no pattern match here]
 codetoanalyze/erlang/nonmatch/src/nonmatch.erl, tail/1, 0, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [*** LATENT ***,no pattern match here]
+codetoanalyze/erlang/nonmatch/src/nonmatch.erl, tail_with_case/1, 1, NONEXHAUSTIVE_PATTERN_MATCH, no_bucket, ERROR, [*** LATENT ***,no pattern match here]
diff --git a/infer/tests/codetoanalyze/erlang/nonmatch/src/nonmatch.erl b/infer/tests/codetoanalyze/erlang/nonmatch/src/nonmatch.erl
index 54ede283c..98f3b82c0 100644
--- a/infer/tests/codetoanalyze/erlang/nonmatch/src/nonmatch.erl
+++ b/infer/tests/codetoanalyze/erlang/nonmatch/src/nonmatch.erl
@@ -21,7 +21,13 @@
     fp_match_test_d_Ok/0,
     match_test_e_Bad/0,
     match_test_f_Ok/0,
-    match_test_g_Bad/0
+    match_test_g_Bad/0,
+    case_test_simple1_Ok/0,
+    case_test_simple2_Ok/0,
+    case_test_simple3_Bad/0,
+    case_test_tail1_Ok/0,
+    case_test_tail2_Ok/0,
+    case_test_tail3_Bad/0
 ]).
 
 tail([_ | Xs]) -> Xs.
@@ -79,6 +85,31 @@ match_test_g_Bad() ->
     X = 2,
     only_accepts_one(X).
 
+case_simple(X) ->
+    case X of
+        0 -> zero;
+        1 -> one
+    end.
+
+tail_with_case(X) ->
+    case X of
+        [_|T] -> T
+    end.
+
+case_test_simple1_Ok() ->
+    case_simple(0).
+case_test_simple2_Ok() ->
+    case_simple(1).
+case_test_simple3_Bad() ->
+    case_simple(2).
+
+case_test_tail1_Ok() ->
+    tail_with_case([1, 2]).
+case_test_tail2_Ok() ->
+    tail_with_case([1]).
+case_test_tail3_Bad() ->
+    tail_with_case([]).
+
 %% internal
 %% These functions are used to fool the compiler, which would warn if these were inlined.