public Map<Reference, Input> inputs() {
        if (inputs.isEmpty() && inherited().isEmpty()) return Map.of();
        if (inherited().isEmpty()) return Collections.unmodifiableMap(inputs);

        // Combine
        Map<Reference, Input> allInputs = new LinkedHashMap<>();

        for (var inheritedProfile : inherited()) {
            for (var input : inheritedProfile.inputs().entrySet()) {
                Input existing = allInputs.get(input.getKey());
                if (existing != null && ! existing.equals(input.getValue()))
                    throw new IllegalArgumentException(this + " inherits " + inheritedProfile + " which contains " +
                                                       input.getValue() + ", but this is already defined as " +
                                                       existing + " in another profile this inherits");
                allInputs.put(input.getKey(), input.getValue());
            }
        }
        allInputs.putAll(inputs);
        return Collections.unmodifiableMap(allInputs);
    }
Returns the inputs of this, which also includes all inputs of the parents of this.
config-model/src/main/java/com/yahoo/schema/RankProfile.java