Improve error processing with syncpipe

src/api/validate-arguments/index.js

@@ -3,6 +3,7 @@
 const isArguments = require("is-arguments");
 const flatten = require("flatten");
 const asExpression = require("as-expression");
+const syncpipe = require("syncpipe");
 
 const ValidationError = require("@validatem/error");
 const annotateErrors = require("@validatem/annotate-errors");
@@ -63,15 +64,12 @@ function applyDefinitions(args, definitions, remainingArgumentsIndex) {
 		};
 	});
 
-	// FIXME: Investigate syncpipe usage here
-	let combinedErrors = results.map((result) => result.errors);
-	let flattenedErrors = flatten(combinedErrors); // TODO: Switch to `Array#flat` once Node 10.x goes EOL (April 2021)
-
-	let newValues = results.map((result) => result.newValue);
-
 	return {
-		errors: flattenedErrors,
-		newValue: newValues
+		errors: syncpipe(results, [
+			(_) => _.map((result) => result.errors),
+			(_) => flatten(_) // TODO: Switch to `Array#flat` once Node 10.x goes EOL (April 2021)
+		]),
+		newValue: results.map((result) => result.newValue)
 	};
 }