Use proper name for constructors in JarInfer (#1167)

Author: msridhar

jar-infer/jar-infer-lib/src/main/java/com/uber/nullaway/jarinfer/DefinitelyDerefedParamsDriver.java

@@ -546,10 +546,15 @@ private static String getAstubxSignature(IMethod mtd) {
         argTypes[i] = getSourceLevelQualifiedTypeName(mtd.getParameterType(argi++));
       }
     }
+    String methodName = mtd.getName().toString();
+    if (methodName.equals("<init>")) {
+      // use simple name of enclosing class
+      methodName = classType.substring(classType.lastIndexOf('.') + 1);
+    }
     return classType
         + ":"
         + (returnType == null ? "void " : returnType + " ")
-        + mtd.getName().toString()
+        + methodName
         + "("
         + String.join(", ", argTypes)
         + ")";

jar-infer/jar-infer-lib/src/test/java/com/uber/nullaway/jarinfer/JarInferTest.java

@@ -563,6 +563,21 @@ public void nestedWildcard() throws Exception {
         "}");
   }
 
+  @Test
+  public void constructors() throws Exception {
+    testTemplate(
+        "constructors",
+        "toys",
+        "TestConstructor",
+        ImmutableMap.of(
+            "toys.TestConstructor:void TestConstructor(java.lang.String)", Sets.newHashSet(0)),
+        "public class TestConstructor {",
+        "  TestConstructor(String s) {",
+        "    s.toString();",
+        "  }",
+        "}");
+  }
+
   @Test
   public void toyJARAnnotatingClasses() throws Exception {
     testAnnotationInJarTemplate(

jar-infer/nullaway-integration-test/src/test/java/com/uber/nullaway/jarinfer/JarInferIntegrationTest.java

@@ -129,6 +129,30 @@ public void wildcards() {
         .doTest();
   }
 
+  @Test
+  public void constructors() {
+    compilationHelper
+        .setArgs(
+            Arrays.asList(
+                "-d",
+                temporaryFolder.getRoot().getAbsolutePath(),
+                "-XepOpt:NullAway:AnnotatedPackages=com.uber",
+                "-XepOpt:NullAway:JarInferEnabled=true",
+                "-XepOpt:NullAway:UnannotatedSubPackages=com.uber.nullaway.[a-zA-Z0-9.]+.unannotated"))
+        .addSourceLines(
+            "Test.java",
+            "package com.uber;",
+            "import org.jspecify.annotations.Nullable;",
+            "import com.uber.nullaway.jarinfer.toys.unannotated.Toys;",
+            "class Test {",
+            "  void test1() {",
+            "    // BUG: Diagnostic contains: passing @Nullable parameter 'null'",
+            "    Toys t = new Toys(null);",
+            "  }",
+            "}")
+        .doTest();
+  }
+
   @Test
   public void jarinferNullableReturnsTest() {
     compilationHelper

jar-infer/test-java-lib-jarinfer/src/main/java/com/uber/nullaway/jarinfer/toys/unannotated/Toys.java

@@ -95,4 +95,8 @@ public static void main(String arg[]) throws java.io.IOException {
       System.out.println(e.getMessage());
     }
   }
+
+  public Toys(String s) {
+    System.out.println(s.toString());
+  }
 }