Make error stream output red

Fixes #130.

package.json

@@ -1,6 +1,6 @@
 {
     "name": "fwdekker.com",
-    "version": "0.36.0",
+    "version": "0.37.0",
     "description": "The source code of [my personal website](https://fwdekker.com/).",
     "author": "Felix W. Dekker",
     "browser": "dist/bundle.js",

src/main/css/main.css

@@ -105,5 +105,5 @@ body {
 
 
 .errorMessage {
-    color: red;
+    color: #FF3333;
 }

src/main/js/Terminal.ts

@@ -60,6 +60,27 @@ export class Terminal {
      * The standard output stream.
      */
     private readonly standardOutput = new Buffer();
+    /**
+     * The standard error stream, actually just a wrapper around the standard output stream.
+     */
+    private readonly standardError = new class extends Buffer {
+        private wrappedBuffer: Buffer;
+
+
+        constructor(wrappedBuffer: Buffer) {
+            super();
+
+            this.wrappedBuffer = wrappedBuffer;
+        }
+
+        read(count: number | undefined = undefined): string {
+            return this.wrappedBuffer.read(count);
+        }
+
+        write(string: string) {
+            this.wrappedBuffer.write(`<span class="errorMessage">${string}</span>`);
+        }
+    }(this.standardOutput);
 
 
     /**
@@ -234,7 +255,7 @@ export class Terminal {
         this.outputText += `${this.prefixText}${this.isInputHidden ? "" : escapeHtml(input)}\n`;
 
         this.standardInput.writeLine(input);
-        this.shell.execute(new StreamSet(this.standardInput, this.standardOutput, this.standardOutput));
+        this.shell.execute(new StreamSet(this.standardInput, this.standardOutput, this.standardError));
 
         let buffer = "";
         while (this.standardOutput.has(1)) {

src/test/Commands.spec.ts

@@ -159,7 +159,6 @@ describe("commands", () => {
             it("executes the command if the previous command exited successfully", () => {
                 environment.set("status", "" + ExitCode.OK);
 
-                // TODO (#129) Run `false` to check that the exit code changes
                 expect(execute("and echo 'message'")).to.equal(ExitCode.OK);
                 expect(readOut()).to.equal("message\n");
             });