Add support for Map.putIfAbsent. (#568)

From the perspective of nullability and Map access paths, this method is equivalent to `Map.put(...)`.
uber · Feb 9, 2022 · 36586e4 · 36586e4
1 parent e1cae62
commit 36586e4
Show file tree

Hide file tree

Showing 2 changed files with 22 additions and 1 deletion.
diff --git a/nullaway/src/main/java/com/uber/nullaway/dataflow/AccessPath.java b/nullaway/src/main/java/com/uber/nullaway/dataflow/AccessPath.java
@@ -557,7 +557,8 @@ public static boolean isContainsKey(Symbol.MethodSymbol symbol, VisitorState sta
   }
 
   public static boolean isMapPut(Symbol.MethodSymbol symbol, VisitorState state) {
-    return NullabilityUtil.isMapMethod(symbol, state, "put", 2);
+    return NullabilityUtil.isMapMethod(symbol, state, "put", 2)
+        || NullabilityUtil.isMapMethod(symbol, state, "putIfAbsent", 2);
   }
 
   /**

diff --git a/nullaway/src/test/java/com/uber/nullaway/NullAwayCoreTests.java b/nullaway/src/test/java/com/uber/nullaway/NullAwayCoreTests.java
@@ -506,6 +506,26 @@ public void testMapGetChainWithCast() {
         .doTest();
   }
 
+  @Test
+  public void testMapPutAndPutIfAbsent() {
+    defaultCompilationHelper
+        .addSourceLines(
+            "Test.java",
+            "package com.uber;",
+            "import java.util.Map;",
+            "class Test {",
+            "   Object testPut(String key, Object o, Map<String, Object> m){",
+            "     m.put(key, o);",
+            "     return m.get(key);",
+            "   }",
+            "   Object testPutIfAbsent(String key, Object o, Map<String, Object> m){",
+            "     m.putIfAbsent(key, o);",
+            "     return m.get(key);",
+            "   }",
+            "}")
+        .doTest();
+  }
+
   @Test
   public void tryFinallySupport() {
     defaultCompilationHelper.addSourceFile("NullAwayTryFinallyCases.java").doTest();