[nullsafe] Fix behaviour of --no-nullsafe-optimistic-third-party-in-default-mode

Summary:
The problem is that in `AnnotatedField.special_case_nullability` we
first check the _generic_ nullability and if it is `nonnullish` we
apply refinements for enums, synthetic fields, etc.

The problem is that the definition of `is_nonnullish` changed in
D25186043 (facebook@7dcbacf) to a stricter one `UncheckedNonnull`, but generic
nullability stayed the same `ThirdPartyNonnull`.

Therefore enum elements were not considered `nonnullish` under
`--no-nullsafe-optimistic-third-party-in-default-mode` and the enum
refinements were not applied, which led to bogus errors.

**Example:**
There's a third-party enum
```
enum EnumClass {
  ENUM_ELEMENT
}
```

`ENUM_ELEMENT` is represented as a private static field of
`EnumClass`.

Then we have first party code that does
```
EnumClass.ENUM_ELEMENT
```

If this first party class is not `Nullsafe` and the checker is ran
with `--no-nullsafe-optimistic-third-party-in-default-mode`, the user
gets an incorrect warning about `ENUM_ELEMENT` being unvetted third
party.

Reviewed By: ngorogiannis

Differential Revision: D25560119

fbshipit-source-id: 4ad0760c5

Author: artempyanykh

infer/src/nullsafe/AnnotatedField.ml

@@ -75,7 +75,11 @@ let get tenv field_name ~class_typ ~class_under_analysis =
       ~is_third_party field_typ annotations
   in
   let special_case_nullability =
-    if Nullability.is_nonnullish (AnnotatedNullability.get_nullability nullability) then
+    if
+      Nullability.is_subtype
+        ~subtype:(AnnotatedNullability.get_nullability nullability)
+        ~supertype:Nullability.ThirdPartyNonnull
+    then
       if
         is_enum_value
         (* Enum values are the special case - they can not be null. So we can strengten nullability.

infer/tests/codetoanalyze/java/nullsafe/NullsafeMode.java

@@ -118,6 +118,10 @@ UncheckedParams OK_passUncheckedToUnchecked() {
       UncheckedParams second = new UncheckedParams(first.copy());
       return second;
     }
+
+    int OK_enumElementsAreNotNull() {
+      return ThirdPartyTestClass.InnerEnum.EA.ordinal();
+    }
   }
 
   @Nullsafe(value = Nullsafe.Mode.LOCAL, trustOnly = @Nullsafe.TrustList({NonNullsafe.class}))

infer/tests/codetoanalyze/java/nullsafe/issues.exp

@@ -217,19 +217,19 @@ codetoanalyze/java/nullsafe/NullMethodCall.java, codetoanalyze.java.nullsafe.Nul
 codetoanalyze/java/nullsafe/NullMethodCall.java, codetoanalyze.java.nullsafe.NullMethodCall.withConditionalAssignemnt(codetoanalyze.java.nullsafe.NullMethodCall$AnotherI,boolean,java.lang.Object,java.lang.Object):void, 2, ERADICATE_NULLABLE_DEREFERENCE, no_bucket, WARNING, [`i` is nullable and is not locally checked for null when calling `withObjectParameter(...)`.], NullMethodCall, codetoanalyze.java.nullsafe
 codetoanalyze/java/nullsafe/NullMethodCall.java, codetoanalyze.java.nullsafe.NullMethodCall.withConjuction(codetoanalyze.java.nullsafe.NullMethodCall$AnotherI,boolean,boolean):void, 1, ERADICATE_NULLABLE_DEREFERENCE, no_bucket, WARNING, [`i` is nullable and is not locally checked for null when calling `withBooleanParameter(...)`.], NullMethodCall, codetoanalyze.java.nullsafe
 codetoanalyze/java/nullsafe/NullsafeMode.java, Linters_dummy_method, 16, ERADICATE_META_CLASS_NEEDS_IMPROVEMENT, no_bucket, INFO, [], NullsafeMode, codetoanalyze.java.nullsafe, issues: 13, curr_mode: "Default"
-codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$NullsafeWithStrictMode.BAD_returnFromNonStrict():java.lang.String, 1, ERADICATE_UNCHECKED_USAGE_IN_NULLSAFE, no_bucket, ERROR, [`NullsafeMode$VariousMethods.returnVal()`: `@Nullsafe(STRICT)` prohibits using values coming from non-strict classes without a check. Result of this call is used at line 174. Either add a local check for null or assertion, or make `NullsafeMode$VariousMethods` nullsafe strict.], NullsafeMode$NullsafeWithStrictMode, codetoanalyze.java.nullsafe
-codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$StrictNullsafe.BAD_dereferenceNotAnnotatedThirdParty():void, 1, ERADICATE_UNVETTED_THIRD_PARTY_IN_NULLSAFE, no_bucket, ERROR, [`ThirdPartyTestClass.returnUnspecified()`: `@Nullsafe` mode prohibits using values coming from not vetted third party methods without a check. Result of this call is used at line 218. Either add a local check for null or assertion, or add the correct signature to nullsafe/third-party-signatures/some.test.pckg.sig.], NullsafeMode$StrictNullsafe, codetoanalyze.java.nullsafe, unvetted_3rd_party:[some.test.pckg.ThirdPartyTestClass#returnUnspecified()]
-codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$StrictNullsafe.BAD_passThirdPartyToUnchecked():codetoanalyze.java.nullsafe.NullsafeMode$UncheckedParams, 1, ERADICATE_UNVETTED_THIRD_PARTY_IN_NULLSAFE, no_bucket, ERROR, [`ThirdPartyTestClass.getUncheckedLong(...)`: `@Nullsafe` mode prohibits using values coming from not vetted third party methods without a check. Result of this call is used at line 214. Either add a local check for null or assertion, or add the correct signature to nullsafe/third-party-signatures/some.test.pckg.sig.], NullsafeMode$StrictNullsafe, codetoanalyze.java.nullsafe, unvetted_3rd_party:[some.test.pckg.ThirdPartyTestClass#getUncheckedLong(long)]
-codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$StrictNullsafe.BAD_returnFromNonNullsafe():java.lang.String, 1, ERADICATE_UNCHECKED_USAGE_IN_NULLSAFE, no_bucket, ERROR, [`NullsafeMode$NonNullsafe.returnVal()`: `@Nullsafe(STRICT)` prohibits using values coming from non-strict classes without a check. Result of this call is used at line 197. Either add a local check for null or assertion, or make `NullsafeMode$NonNullsafe` nullsafe strict.], NullsafeMode$StrictNullsafe, codetoanalyze.java.nullsafe
+codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$NullsafeWithStrictMode.BAD_returnFromNonStrict():java.lang.String, 1, ERADICATE_UNCHECKED_USAGE_IN_NULLSAFE, no_bucket, ERROR, [`NullsafeMode$VariousMethods.returnVal()`: `@Nullsafe(STRICT)` prohibits using values coming from non-strict classes without a check. Result of this call is used at line 178. Either add a local check for null or assertion, or make `NullsafeMode$VariousMethods` nullsafe strict.], NullsafeMode$NullsafeWithStrictMode, codetoanalyze.java.nullsafe
+codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$StrictNullsafe.BAD_dereferenceNotAnnotatedThirdParty():void, 1, ERADICATE_UNVETTED_THIRD_PARTY_IN_NULLSAFE, no_bucket, ERROR, [`ThirdPartyTestClass.returnUnspecified()`: `@Nullsafe` mode prohibits using values coming from not vetted third party methods without a check. Result of this call is used at line 222. Either add a local check for null or assertion, or add the correct signature to nullsafe/third-party-signatures/some.test.pckg.sig.], NullsafeMode$StrictNullsafe, codetoanalyze.java.nullsafe, unvetted_3rd_party:[some.test.pckg.ThirdPartyTestClass#returnUnspecified()]
+codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$StrictNullsafe.BAD_passThirdPartyToUnchecked():codetoanalyze.java.nullsafe.NullsafeMode$UncheckedParams, 1, ERADICATE_UNVETTED_THIRD_PARTY_IN_NULLSAFE, no_bucket, ERROR, [`ThirdPartyTestClass.getUncheckedLong(...)`: `@Nullsafe` mode prohibits using values coming from not vetted third party methods without a check. Result of this call is used at line 218. Either add a local check for null or assertion, or add the correct signature to nullsafe/third-party-signatures/some.test.pckg.sig.], NullsafeMode$StrictNullsafe, codetoanalyze.java.nullsafe, unvetted_3rd_party:[some.test.pckg.ThirdPartyTestClass#getUncheckedLong(long)]
+codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$StrictNullsafe.BAD_returnFromNonNullsafe():java.lang.String, 1, ERADICATE_UNCHECKED_USAGE_IN_NULLSAFE, no_bucket, ERROR, [`NullsafeMode$NonNullsafe.returnVal()`: `@Nullsafe(STRICT)` prohibits using values coming from non-strict classes without a check. Result of this call is used at line 201. Either add a local check for null or assertion, or make `NullsafeMode$NonNullsafe` nullsafe strict.], NullsafeMode$StrictNullsafe, codetoanalyze.java.nullsafe
 codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustAllNullsafe.BAD_passThirdPartyToUnchecked():codetoanalyze.java.nullsafe.NullsafeMode$UncheckedParams, 1, ERADICATE_UNVETTED_THIRD_PARTY_IN_NULLSAFE, no_bucket, ERROR, [`ThirdPartyTestClass.getUncheckedLong(...)`: `@Nullsafe` mode prohibits using values coming from not vetted third party methods without a check. Result of this call is used at line 113. Either add a local check for null or assertion, or add the correct signature to nullsafe/third-party-signatures/some.test.pckg.sig.], NullsafeMode$TrustAllNullsafe, codetoanalyze.java.nullsafe, unvetted_3rd_party:[some.test.pckg.ThirdPartyTestClass#getUncheckedLong(long)]
 codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustAllNullsafe.BAD_returnFromUnvettedThirdParty():java.lang.String, 1, ERADICATE_UNVETTED_THIRD_PARTY_IN_NULLSAFE, no_bucket, ERROR, [`ThirdPartyTestClass.returnUnspecified()`: `@Nullsafe` mode prohibits using values coming from not vetted third party methods without a check. Result of this call is used at line 92. Either add a local check for null or assertion, or add the correct signature to nullsafe/third-party-signatures/some.test.pckg.sig.], NullsafeMode$TrustAllNullsafe, codetoanalyze.java.nullsafe, unvetted_3rd_party:[some.test.pckg.ThirdPartyTestClass#returnUnspecified()]
 codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustAllNullsafe.BAD_returnNonNullableFieldFromThirdParty():java.lang.String, 1, ERADICATE_UNVETTED_THIRD_PARTY_IN_NULLSAFE, no_bucket, ERROR, [`ThirdPartyTestClass.nonNullableField`: `@Nullsafe` mode prohibits using values coming from not vetted third party fields without a check. This field is used at line 100. Either add a local check for null or assertion, or access `nonNullableField` via a nullsafe getter.], NullsafeMode$TrustAllNullsafe, codetoanalyze.java.nullsafe
 codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustAllNullsafe.BAD_returnNullFromNonNulsafe():java.lang.String, 0, ERADICATE_RETURN_NOT_NULLABLE, no_bucket, ERROR, [`BAD_returnNullFromNonNulsafe()`: return type is declared non-nullable but the method returns a nullable value: call to returnNull() at line 89.], NullsafeMode$TrustAllNullsafe, codetoanalyze.java.nullsafe, nullable_methods:codetoanalyze.java.nullsafe.NullsafeMode$VariousMethods.returnNull at 89
 codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustAllNullsafe.BAD_returnNullableFieldFromThirdParty():java.lang.String, 0, ERADICATE_RETURN_NOT_NULLABLE, no_bucket, ERROR, [`BAD_returnNullableFieldFromThirdParty()`: return type is declared non-nullable but the method returns a nullable value: field nullableField at line 97.], NullsafeMode$TrustAllNullsafe, codetoanalyze.java.nullsafe
-codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustNoneNullsafe.BAD_returnFromNonNullsafe():java.lang.String, 1, ERADICATE_UNCHECKED_USAGE_IN_NULLSAFE, no_bucket, ERROR, [`NullsafeMode$NonNullsafe.returnVal()`: `@Nullsafe(trust={...})` prohibits using values coming from non-`@Nullsafe` classes without a check, unless the class is in the trust list. Result of this call is used at line 154. Either add a local check for null or assertion, or make `NullsafeMode$NonNullsafe` @Nullsafe (or add it to trust list).], NullsafeMode$TrustNoneNullsafe, codetoanalyze.java.nullsafe
-codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustSomeNullsafe.BAD_returnFromUntrustedNonNullsafe():java.lang.String, 1, ERADICATE_UNCHECKED_USAGE_IN_NULLSAFE, no_bucket, ERROR, [`NullsafeMode$VariousMethods.returnVal()`: `@Nullsafe(trust={...})` prohibits using values coming from non-`@Nullsafe` classes without a check, unless the class is in the trust list. Result of this call is used at line 134. Either add a local check for null or assertion, or make `NullsafeMode$VariousMethods` @Nullsafe (or add it to trust list).], NullsafeMode$TrustSomeNullsafe, codetoanalyze.java.nullsafe
-codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustSomeNullsafe.BAD_returnNullFromNonNulsafe():java.lang.String, 0, ERADICATE_RETURN_NOT_NULLABLE, no_bucket, ERROR, [`BAD_returnNullFromNonNulsafe()`: return type is declared non-nullable but the method returns a nullable value: call to returnNull() at line 144.], NullsafeMode$TrustSomeNullsafe, codetoanalyze.java.nullsafe, nullable_methods:codetoanalyze.java.nullsafe.NullsafeMode$VariousMethods.returnNull at 144
-codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustSomeNullsafe.FP_OK_accessFieldFromNonNullsafe():java.lang.String, 1, ERADICATE_UNCHECKED_USAGE_IN_NULLSAFE, no_bucket, ERROR, [`NullsafeMode$NonNullsafe.valField`: `@Nullsafe(trust={...})` prohibits using values coming from non-`@Nullsafe` classes without a check, unless the class is in the trust list. This field is used at line 147. Either add a local check for null or assertion, or make `NullsafeMode$NonNullsafe` @Nullsafe (or add it to trust list).], NullsafeMode$TrustSomeNullsafe, codetoanalyze.java.nullsafe
+codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustNoneNullsafe.BAD_returnFromNonNullsafe():java.lang.String, 1, ERADICATE_UNCHECKED_USAGE_IN_NULLSAFE, no_bucket, ERROR, [`NullsafeMode$NonNullsafe.returnVal()`: `@Nullsafe(trust={...})` prohibits using values coming from non-`@Nullsafe` classes without a check, unless the class is in the trust list. Result of this call is used at line 158. Either add a local check for null or assertion, or make `NullsafeMode$NonNullsafe` @Nullsafe (or add it to trust list).], NullsafeMode$TrustNoneNullsafe, codetoanalyze.java.nullsafe
+codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustSomeNullsafe.BAD_returnFromUntrustedNonNullsafe():java.lang.String, 1, ERADICATE_UNCHECKED_USAGE_IN_NULLSAFE, no_bucket, ERROR, [`NullsafeMode$VariousMethods.returnVal()`: `@Nullsafe(trust={...})` prohibits using values coming from non-`@Nullsafe` classes without a check, unless the class is in the trust list. Result of this call is used at line 138. Either add a local check for null or assertion, or make `NullsafeMode$VariousMethods` @Nullsafe (or add it to trust list).], NullsafeMode$TrustSomeNullsafe, codetoanalyze.java.nullsafe
+codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustSomeNullsafe.BAD_returnNullFromNonNulsafe():java.lang.String, 0, ERADICATE_RETURN_NOT_NULLABLE, no_bucket, ERROR, [`BAD_returnNullFromNonNulsafe()`: return type is declared non-nullable but the method returns a nullable value: call to returnNull() at line 148.], NullsafeMode$TrustSomeNullsafe, codetoanalyze.java.nullsafe, nullable_methods:codetoanalyze.java.nullsafe.NullsafeMode$VariousMethods.returnNull at 148
+codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustSomeNullsafe.FP_OK_accessFieldFromNonNullsafe():java.lang.String, 1, ERADICATE_UNCHECKED_USAGE_IN_NULLSAFE, no_bucket, ERROR, [`NullsafeMode$NonNullsafe.valField`: `@Nullsafe(trust={...})` prohibits using values coming from non-`@Nullsafe` classes without a check, unless the class is in the trust list. This field is used at line 151. Either add a local check for null or assertion, or make `NullsafeMode$NonNullsafe` @Nullsafe (or add it to trust list).], NullsafeMode$TrustSomeNullsafe, codetoanalyze.java.nullsafe
 codetoanalyze/java/nullsafe/NullsafeMode.java, codetoanalyze.java.nullsafe.NullsafeMode$TrustSomeNullsafe.OK_returnFromUntrustedNonNullsafeAsNullable():java.lang.String, 0, ERADICATE_RETURN_OVER_ANNOTATED, no_bucket, ADVICE, [Method `OK_returnFromUntrustedNonNullsafeAsNullable()` is annotated with `@Nullable` but never returns null.], NullsafeMode$TrustSomeNullsafe, codetoanalyze.java.nullsafe
 codetoanalyze/java/nullsafe/NullsafeModeNestedClasses.java, Linters_dummy_method, 14, ERADICATE_META_CLASS_NEEDS_IMPROVEMENT, no_bucket, INFO, [], NullsafeLocal, codetoanalyze.java.nullsafe, issues: 5, curr_mode: "LocalTrustAll"
 codetoanalyze/java/nullsafe/NullsafeModeNestedClasses.java, Linters_dummy_method, 49, ERADICATE_REDUNDANT_NESTED_CLASS_ANNOTATION, no_bucket, ADVICE, [`NullsafeLocal$NestedExplicitLocal`: the same @Nullsafe mode is already specified in the outer class, so this annotation can be removed.], NullsafeLocal$NestedExplicitLocal, codetoanalyze.java.nullsafe

infer/tests/codetoanalyze/java/nullsafe/third-party-test-code/some/test/pckg/ThirdPartyTestClass.java

@@ -16,6 +16,8 @@
  */
 public class ThirdPartyTestClass {
 
+  // Inner classes
+
   public static class UncheckedLong {
     public long mInner;
 
@@ -24,6 +26,11 @@ public UncheckedLong(long inner) {
     }
   }
 
+  public enum InnerEnum {
+    EA,
+    EB,
+  }
+
   // Fields.
 
   public String nonNullableField;