Allow newlines in output of echo

Fixes #145.

package.json

@@ -1,6 +1,6 @@
 {
     "name": "fwdekker.com",
-    "version": "0.39.1",
+    "version": "0.39.2",
     "description": "The source code of [my personal website](https://fwdekker.com/).",
     "author": "Felix W. Dekker",
     "browser": "dist/bundle.js",

src/main/js/Commands.ts

@@ -515,19 +515,22 @@ return new Command(
     "echo": /* language=JavaScript */ `\
 return new Command(
     (input, streams) => {
-        const message = input.args.join(" ").replace("hunter2", "*******");
-
-        if (input.hasAnyOption("-n", "--newline"))
-            streams.out.write(message);
-        else
-            streams.out.writeLine(message);
+        let message = input.args.join(" ").replace("hunter2", "*******");
+        if (input.hasAnyOption("-e", "--escapes"))
+            message = message.replace(/\\\\n/g, "\\n");
+        if (!input.hasAnyOption("-n", "--newline"))
+            message = message + "\\n";
 
+        streams.out.write(message);
         return ExitCode.OK;
     },
     \`display text\`,
-    \`echo [<b>-n</b> | <b>--newline</b>] [<u>text</u> <u>...</u>]\`,
+    \`echo [<b>-e</b> | <b>--escapes</b>] [<b>-n</b> | <b>--newline</b>] [<u>text</u> <u>...</u>]\`,
     \`Displays each <u>text</u> separated by a single whitespace.
 
+    If the <b>--escapes</b> parameter is given, the newline escape sequence "\\\\n" is replaced by an actual newline
+    character.
+
     Unless the <b>--newline</b> parameter is given, a newline is appended to the end.\`.trimMultiLines(),
     new InputValidator()
 )`,
@@ -538,8 +541,10 @@ return new Command(
         return parseInt(input.args[0] || "0");
     },
     \`close session\`,
-    \`exit\`,
-    \`Closes the terminal session.\`,
+    \`exit [<u>status</u>]\`,
+    \`Closes the terminal session.
+
+    Returns status code <u>status</u> if it is defined, and returns 0 otherwise.\`,
     new InputValidator({minArgs: 0, maxArgs: 1})
 )`,
     "false": /* language=JavaScript */ `\

src/test/Commands.spec.ts

@@ -345,14 +345,28 @@ describe("commands", () => {
             beforeEach(() => loadCommand("echo"));
 
 
-            it("adds a newline to the end by default", () => {
-                expect(execute("echo a b c \n")).to.equal(ExitCode.OK);
-                expect(readOut()).to.equal("a b c \n\n");
+            describe("--escapes", () => {
+                it("does not unescape newlines by default", () => {
+                    expect(execute("echo 'a b \\n c'")).to.equal(ExitCode.OK);
+                    expect(readOut()).to.equal("a b \\n c\n");
+                });
+
+                it("unescapes newlines if prompted to do so", () => {
+                    expect(execute("echo -e 'a b \\n c'")).to.equal(ExitCode.OK);
+                    expect(readOut()).to.equal("a b \n c\n");
+                });
             });
 
-            it("does not add a newline if prompted to do so", () => {
-                expect(execute("echo -n a b c")).to.equal(ExitCode.OK);
-                expect(readOut()).to.equal("a b c");
+            describe("--newline", () => {
+                it("adds a newline to the end by default, even if there is already a newline", () => {
+                    expect(execute("echo a b c \n")).to.equal(ExitCode.OK);
+                    expect(readOut()).to.equal("a b c \n\n");
+                });
+
+                it("does not add a newline if prompted to do so", () => {
+                    expect(execute("echo -n a b c")).to.equal(ExitCode.OK);
+                    expect(readOut()).to.equal("a b c");
+                });
             });
         });