Refactored STArray Class (#85)

Refactored STArray and pushed end-byte computations into the STArray and STObject classes.

packages/ripple-binary-codec/src/serdes/binary-serializer.ts

@@ -1,5 +1,5 @@
 import * as assert from "assert";
-import { Field, FieldInstance } from "../enums";
+import { FieldInstance } from "../enums";
 
 /**
  * Bytes list is a collection of buffer objects
@@ -133,11 +133,6 @@ class BinarySerializer {
       this.writeLengthEncoded(associatedValue);
     } else {
       associatedValue.toBytesSink(this.sink);
-      if (field.type.name === "STObject") {
-        this.sink.put(Field["ObjectEndMarker"].header);
-      } else if (field.type.name === "STArray") {
-        this.sink.put(Field["ArrayEndMarker"].header);
-      }
     }
   }
 

packages/ripple-binary-codec/src/types/path-set.ts

@@ -171,7 +171,7 @@ class Path extends SerializedTypeClass {
    */
   toJSON() {
     const json: Array<HopObject> = [];
-    const pathParser = new BinaryParser(this.bytes.toString("hex"));
+    const pathParser = new BinaryParser(this.toString());
 
     while (!pathParser.end()) {
       json.push(Hop.fromParser(pathParser).toJSON());
@@ -236,7 +236,7 @@ class PathSet extends SerializedTypeClass {
    */
   toJSON(): Array<Array<HopObject>> {
     const json: Array<Array<HopObject>> = [];
-    const pathParser = new BinaryParser(this.bytes.toString("hex"));
+    const pathParser = new BinaryParser(this.toString());
 
     while (!pathParser.end()) {
       json.push(Path.fromParser(pathParser).toJSON());

packages/ripple-binary-codec/src/types/st-array.ts

@@ -1,37 +1,83 @@
-import { makeClass } from "../utils/make-class";
-import { ensureArrayLikeIs, SerializedType } from "./serialized-type";
+import { SerializedTypeClass } from "./serialized-type";
 import { STObject } from "./st-object";
+import { BinaryParser } from "../serdes/binary-parser";
 
-const STArray = makeClass(
-  {
-    mixins: SerializedType,
-    inherits: Array,
-    statics: {
-      fromParser(parser) {
-        const array = new STArray();
-        while (!parser.end()) {
-          const field = parser.readField();
-          if (field.name === "ArrayEndMarker") {
-            break;
-          }
-          const outer = new STObject();
-          outer[field.name] = parser.readFieldValue(field);
-          array.push(outer);
-        }
-        return array;
-      },
-      from(value) {
-        return ensureArrayLikeIs(STArray, value).withChildren(STObject);
-      },
-    },
-    toJSON() {
-      return this.map((v) => v.toJSON());
-    },
-    toBytesSink(sink) {
-      this.forEach((so) => so.toBytesSink(sink));
-    },
-  },
-  undefined
-);
+const ARRAY_END_MARKER = 0xf1;
+const OBJECT_END_MARKER = 0xe1;
+
+/**
+ * Class for serializing and deserializing Arrays of Objects
+ */
+class STArray extends SerializedTypeClass {
+  /**
+   * Construct an STArray from a BinaryParser
+   *
+   * @param parser BinaryParser to parse an STArray from
+   * @returns An STArray Object
+   */
+  static fromParser(parser: BinaryParser): STArray {
+    const bytes: Array<Buffer> = [];
+
+    while (!parser.end()) {
+      const field = parser.readField();
+      if (field.name === "ArrayEndMarker") {
+        break;
+      }
+
+      bytes.push(
+        field.header,
+        parser.readFieldValue(field).toBytes(),
+        Buffer.from([OBJECT_END_MARKER])
+      );
+    }
+
+    bytes.push(Buffer.from([ARRAY_END_MARKER]));
+    return new STArray(Buffer.concat(bytes));
+  }
+
+  /**
+   * Construct an STArray from an Array of JSON Objects
+   *
+   * @param value STArray or Array of Objects to parse into an STArray
+   * @returns An STArray object
+   */
+  static from(value: STArray | Array<object>): STArray {
+    if (value instanceof STArray) {
+      return value;
+    }
+
+    const bytes: Array<Buffer> = [];
+    value.forEach((obj) => {
+      bytes.push(STObject.from(obj).toBytes());
+    });
+
+    bytes.push(Buffer.from([ARRAY_END_MARKER]));
+    return new STArray(Buffer.concat(bytes));
+  }
+
+  /**
+   * Return the JSON representation of this.bytes
+   *
+   * @returns An Array of JSON objects
+   */
+  toJSON(): Array<object> {
+    const result: Array<object> = [];
+
+    const arrayParser = new BinaryParser(this.toString());
+
+    while (!arrayParser.end()) {
+      const field = arrayParser.readField();
+      if (field.name === "ArrayEndMarker") {
+        break;
+      }
+
+      const outer = {};
+      outer[field.name] = STObject.fromParser(arrayParser).toJSON();
+      result.push(outer);
+    }
+
+    return result;
+  }
+}
 
 export { STArray };

packages/ripple-binary-codec/src/types/st-object.ts

@@ -67,6 +67,9 @@ const STObject = makeClass(
           return;
         }
         serializer.writeFieldAndValue(field, value);
+        if (field.type.name === "STObject") {
+          serializer.put(Buffer.from([0xe1]));
+        }
       });
     },
   },