[cost] Add models for Java Set

Summary: Although `Set.contains` could be logarithmic in the worst case, on average, the contains() runs in O(1) time. We rather take the average here, following the most common case.

Reviewed By: ngorogiannis

Differential Revision: D27078794

fbshipit-source-id: 24e3476e8

infer/src/bufferoverrun/bufferOverrunModels.ml

@@ -1903,6 +1903,7 @@ module Call = struct
         &:: "singletonMap" <>--> Collection.singleton_collection
       ; +PatternMatch.Java.implements_collections
         &::+ unmodifiable <>$ capt_exp $--> Collection.iterator
+      ; +PatternMatch.Java.implements_set &:: "of" &++> Collection.of_list
       ; +PatternMatch.Java.implements_google "common.collect.ImmutableSet"
         &:: "of" &++> Collection.of_list
       ; +PatternMatch.Java.implements_google "common.base.Preconditions"

infer/src/cost/costModels.ml

@@ -274,6 +274,13 @@ module Call = struct
         ; +PatternMatch.Java.implements_arrays
           &:: "sort" $ capt_exp
           $+...$--> BoundsOfArray.n_log_n_length ~of_function:"Arrays.sort"
+        ; +PatternMatch.Java.implements_set &:: "contains" <>$ any_arg $+ any_arg
+          $--> unit_cost_model
+        ; +PatternMatch.Java.implements_set &:: "containsAll" <>$ any_arg $+ capt_exp
+          $--> BoundsOfCollection.linear_length ~of_function:"Set.containsAll"
+        ; +PatternMatch.Java.implements_collection
+          &:: "removeAll" <>$ any_arg $+ capt_exp
+          $--> BoundsOfCollection.linear_length ~of_function:"Collection.removeAll"
         ; +PatternMatch.Java.implements_list
           &:: "contains" <>$ capt_exp
           $+...$--> BoundsOfCollection.linear_length ~of_function:"List.contains"

infer/tests/codetoanalyze/java/performance/SetTest.java

@@ -0,0 +1,38 @@
+/*
+ * 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.
+ */
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.Set;
+
+class SetTest {
+
+  // // Set.of creates an immutable set
+  // private static final Set<String> StaticSet = Set.of("a");
+
+  void contains_empty_constant(HashSet<String> set) {
+    set.contains("");
+  }
+
+  void containsAll_linear(Set<String> set, ArrayList<String> list) {
+    set.containsAll(list);
+  }
+
+  void removeAll_linear(HashSet<String> set, ArrayList<String> list) {
+    set.removeAll(list);
+  }
+
+  // void loop_of_constant() {
+  //   Set<String> my_set = Set.of("a", "b", "c", "d", "e", "f", "g");
+  //   for (String el : my_set) {}
+  // }
+
+  // // here, we cannot yet recognize that StaticSet is an immutable set
+  // // created by Set.of operation in the class initializer.
+  // void immutable_set_of_constant_FP() {
+  //   for (int i = 0; i <= StaticSet.size(); i++) {}
+  // }
+}

infer/tests/codetoanalyze/java/performance/cost-issues.exp

@@ -322,6 +322,10 @@ codetoanalyze/java/performance/PreconditionTest.java, PreconditionTest.checkArgu
 codetoanalyze/java/performance/PreconditionTest.java, PreconditionTest.checkNotNull_linear(java.util.ArrayList,java.lang.Object):void, 12 + 8 ⋅ list.length + 3 ⋅ (list.length + 1),  OnUIThread:false, [{list.length + 1},Loop,{list.length},Loop]
 codetoanalyze/java/performance/PreconditionTest.java, PreconditionTest.checkState_constant(java.util.ArrayList):void, 23,  OnUIThread:false, []
 codetoanalyze/java/performance/PreconditionTest.java, PreconditionTest.constant_array(int[]):void, 36,  OnUIThread:false, []
+codetoanalyze/java/performance/SetTest.java, SetTest.<init>(), 2,  OnUIThread:false, []
+codetoanalyze/java/performance/SetTest.java, SetTest.containsAll_linear(java.util.Set,java.util.ArrayList):void, 3 + list.length,  OnUIThread:false, [{list.length},Modeled call to Set.containsAll]
+codetoanalyze/java/performance/SetTest.java, SetTest.contains_empty_constant(java.util.HashSet):void, 3,  OnUIThread:false, []
+codetoanalyze/java/performance/SetTest.java, SetTest.removeAll_linear(java.util.HashSet,java.util.ArrayList):void, 3 + list.length,  OnUIThread:false, [{list.length},Modeled call to Collection.removeAll]
 codetoanalyze/java/performance/StringBuilderTest.java, StringBuilderTest.<init>(), 2,  OnUIThread:false, []
 codetoanalyze/java/performance/StringBuilderTest.java, StringBuilderTest.append_linear(java.lang.String):void, 23 + 5 ⋅ (s.length + 2) + 3 ⋅ (s.length + 3),  OnUIThread:false, [{s.length + 3},Call to void StringBuilderTest.new_linear(String),Loop,{s.length + 2},Call to void StringBuilderTest.new_linear(String),Loop]
 codetoanalyze/java/performance/StringBuilderTest.java, StringBuilderTest.new_capacity_constant():void, 22,  OnUIThread:false, []