private Type substituteTypeArgsInGenericMethodType()

in nullaway/src/main/java/com/uber/nullaway/generics/GenericsChecks.java [1898:1945]
43 lines of code
7 McCabe index (conditional complexity)

  private Type substituteTypeArgsInGenericMethodType(
      Tree tree,
      Type.ForAll forAllType,
      @Nullable TreePath path,
      VisitorState state,
      boolean calledFromDataflow) {
    Type.MethodType methodType = forAllType.asMethodType();

    List<? extends Tree> typeArgumentTrees =
        (tree instanceof MethodInvocationTree methodInvocationTree)
            ? methodInvocationTree.getTypeArguments()
            : ((NewClassTree) tree).getTypeArguments();
    com.sun.tools.javac.util.List<Type> explicitTypeArgs = convertTreesToTypes(typeArgumentTrees);

    // There are no explicit type arguments, so use the inferred types
    if (explicitTypeArgs.isEmpty() && tree instanceof MethodInvocationTree invocationTree) {
      MethodInferenceResult result = inferredTypeVarNullabilityForGenericCalls.get(tree);
      if (result == null) {
        // have not yet attempted inference for this call
        InvocationAndContext invocationAndType =
            path == null
                ? new InvocationAndContext(invocationTree, null, false)
                : getInvocationAndContextForInference(path, state, calledFromDataflow);
        result =
            runInferenceForCall(
                state,
                path,
                invocationAndType.invocation,
                invocationAndType.typeFromAssignmentContext,
                invocationAndType.assignedToLocal,
                calledFromDataflow);
      }
      Type.MethodType methodTypeAtCallSite =
          castToNonNull(ASTHelpers.getType(invocationTree.getMethodSelect())).asMethodType();
      if (result instanceof InferenceSuccess successResult) {
        methodTypeAtCallSite =
            restoreNestedNullabilityForTypeVarArguments(
                invocationTree, methodType, methodTypeAtCallSite, state);
        return TypeSubstitutionUtils.updateMethodTypeWithInferredNullability(
            methodTypeAtCallSite, methodType, successResult.typeVarNullability, state, config);
      } else {
        // inference failed; just return the method type at the call site with no substitutions
        return methodTypeAtCallSite;
      }
    }
    return TypeSubstitutionUtils.subst(
        state.getTypes(), methodType, forAllType.tvars, explicitTypeArgs, config);
  }