MapboxDirections builder throws Exception when approaches is empty.

[Lebedinsky]

Bug Report

Expected Behavior

MapboxDirections.Builder#build() should not throw exception when approaches array is empty.

Current Behavior

MapboxDirections.Builder#build() throws ServicesException exception when approaches array is empty.

Possible Solution

Cause of this issue is we trying to compare size of approaches and coordinates. But actually, we should compare size of approaches and waypointIndices.

Steps to Reproduce

1. Set approaches as empty array.
2. Call MapboxDirections#build() method.

Context (Environment)

We want to avoid using nullable types in Navigation SDK. So before we set nulls (waypointIndices, waypointNames, approaches) to builder and it works, but now we will send empty arrays instead of nulls.

[Guardiola31337]

Was this addressed in #1118 and #1121? Are we good to close here? @Lebedinsky @korshaknn

[korshaknn]

@Guardiola31337 no, it was not addressed. logic inside MapboxDirections was not changed

if (!approaches.isEmpty()) {
        if (approaches.size() != coordinates.size()) {
          throw new ServicesException("Number of approach elements must match "
            + "number of coordinates provided.");
        }
        String formattedApproaches = FormatUtils.formatApproaches(approaches);
        if (formattedApproaches == null) {
          throw new ServicesException("All approaches values must be one of curb, unrestricted");
        }
        approaches(formattedApproaches);
}

[Guardiola31337]

Thanks for confirming @korshaknn 🙇

[Lebedinsky]

@Guardiola31337 Not sure, because as we can see here FormatUtils#formatApproaches() method we still can return null, and as I see we pass this potentially null-string to MapboxDirections builder.

[RingerJK]

@Guardiola31337 no, it was not addressed. logic inside MapboxDirections was not changed

if (!approaches.isEmpty()) {
        if (approaches.size() != coordinates.size()) {
          throw new ServicesException("Number of approach elements must match "
            + "number of coordinates provided.");
        }
        String formattedApproaches = FormatUtils.formatApproaches(approaches);
        if (formattedApproaches == null) {
          throw new ServicesException("All approaches values must be one of curb, unrestricted");
        }
        approaches(formattedApproaches);
}

we're good to close the issue, approaches' list is NonNull and here we check that it's not null. Logic inside block, after check approaches is not null is right. The problem was with legacy when approaches were checked if null only(but not if empty)