ESM: Ported Tidy operations. Updated portOperation script to attempt to find the run function and list related constants.

src/core/operations/TakeBytes.mjs

@@ -0,0 +1,86 @@
+/**
+ * @author n1474335 [n1474335@gmail.com]
+ * @copyright Crown Copyright 2016
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+
+/**
+ * Take bytes operation
+ */
+class TakeBytes extends Operation {
+
+    /**
+     * TakeBytes constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Take bytes";
+        this.module = "Default";
+        this.description = "Takes a slice of the specified number of bytes from the data.";
+        this.inputType = "ArrayBuffer";
+        this.outputType = "ArrayBuffer";
+        this.args = [
+            {
+                "name": "Start",
+                "type": "number",
+                "value": 0
+            },
+            {
+                "name": "Length",
+                "type": "number",
+                "value": 5
+            },
+            {
+                "name": "Apply to each line",
+                "type": "boolean",
+                "value": false
+            }
+        ];
+    }
+
+    /**
+     * @param {ArrayBuffer} input
+     * @param {Object[]} args
+     * @returns {ArrayBuffer}
+     */
+    run(input, args) {
+        const start = args[0],
+            length = args[1],
+            applyToEachLine = args[2];
+
+        if (start < 0 || length < 0)
+            throw "Error: Invalid value";
+
+        if (!applyToEachLine)
+            return input.slice(start, start+length);
+
+        // Split input into lines
+        const data = new Uint8Array(input);
+        const lines = [];
+        let line = [],
+            i;
+
+        for (i = 0; i < data.length; i++) {
+            if (data[i] === 0x0a) {
+                lines.push(line);
+                line = [];
+            } else {
+                line.push(data[i]);
+            }
+        }
+        lines.push(line);
+
+        let output = [];
+        for (i = 0; i < lines.length; i++) {
+            output = output.concat(lines[i].slice(start, start+length));
+            output.push(0x0a);
+        }
+        return new Uint8Array(output.slice(0, output.length-1)).buffer;
+    }
+
+}
+
+export default TakeBytes;