Detect non-streams and improve error reporting

index.js

@@ -16,13 +16,17 @@ module.exports = function pipe(streams) {
 	
 		function getPipeline(source) {
 			if (!boundPipelineCache.has(source)) {
-				let pipeline = existentStreams.reduce((bound, stream) => {
-					if (stream.read == null) {
-						throw new Error(`Stream is missing a read handler (stream description: ${stream.description})`);
+				let pipeline = existentStreams.reduce((bound, stream, i) => {
+					// TODO: Use Validatem for this instead
+					// FIXME: Stream index is currently wrong if there were any nulls in the streams list, correct for this
+					if (!(typeof stream === "object") || Array.isArray(stream)) {
+						throw new Error(`Value at index ${i} in the pipeline is not a stream`);
+					} else if (stream.read == null) {
+						throw new Error(`Stream at index ${i} is missing a read handler (stream description: ${stream.description})`);
 					} else if (stream.abort == null) {
-						throw new Error(`Stream is missing an abort handler (stream description: ${stream.description})`);
+						throw new Error(`Stream at index ${i} is missing an abort handler (stream description: ${stream.description})`);
 					} else if (stream.peek == null) {
-						throw new Error(`Stream is missing a peek handler (stream description: ${stream.description})`);
+						throw new Error(`Stream at index ${i} is missing a peek handler (stream description: ${stream.description})`);
 					} else {
 						if (bound != null) {
 							return Object.assign({}, stream, {