@Nullable
	public String getReverseVariableMapping(@Nonnull String owner, @Nonnull String methodName, @Nonnull String methodDesc,
	                                        @Nonnull String varName, @Nonnull String varDesc, int varIndex) {
		String originalOwnerName = getReverseClassMapping(owner);
		if (originalOwnerName == null)
			originalOwnerName = owner;

		// Get methods in the original class
		List<MethodMapping> methodMappings = methods.get(originalOwnerName);
		if (methodMappings == null || methodMappings.isEmpty())
			return null;

		String originalMethodDesc = reverseMapper.mapDesc(methodDesc);
		String originalVarDesc = reverseMapper.mapDesc(varDesc);
		for (MethodMapping methodMapping : methodMappings) {
			// The current name must match the mappings "new" name
			if (!methodName.equals(methodMapping.getNewName()))
				continue;

			// The original method descriptor must match the mapping key's
			if (originalMethodDesc.equals(methodMapping.getDesc())) {
				// Get the variables that were mapped under the original name
				List<VariableMapping> variableMappings = variables.get(varKey(originalOwnerName, methodMapping.getOldName(), originalMethodDesc));
				for (VariableMapping variableMapping : variableMappings) {
					// If the variable index, name, and descriptor match, yield the variable mapping's original name
					if (variableMapping.getIndex() == varIndex && variableMapping.getNewName().equals(varName)) {
						if (varDesc.equals(originalVarDesc)) {
							return variableMapping.getOldName();
						}
					}
				}
			}
		}
		return null;
	}
@param owner
		Current class name.
@param methodName
		Current method name.
@param methodDesc
		Current method descriptor.
@param varName
		Current variable name.
@param varDesc
		Current variable descriptor.
@param varIndex
		Variable index.

@return Original name of the variable if any mappings exist.
{@code null} if the variable has not been mapped.
recaf-core/src/main/java/software/coley/recaf/services/mapping/aggregate/AggregatedMappings.java