Implement cat command with -n and -b support

Author: shreefAhmedM

implement-shell-tools/cat/cat.js

@@ -0,0 +1,50 @@
+const fs = require("fs");
+
+const args = process.argv.slice(2);
+
+let flag = "";
+let lineNumber = 1;
+
+for (const arg of args) {
+
+    // Check for flags
+    if (arg === "-n" || arg === "-b") {
+        flag = arg;
+        continue;
+    }
+
+    // Read the file
+    const content = fs.readFileSync(arg, "utf8");
+
+    // split into lines
+    const lines = content.split("\n");
+
+    // Remove the extra empty line if the file ends with a new line
+    if (lines[lines.length - 1] === "") {
+        lines.pop();
+    }
+
+ 
+    for (const line of lines) {
+
+        if (flag === "-n") {
+            console.log(`${lineNumber}\t${line}`);
+            lineNumber++;
+        }
+
+        else if (flag === "-b") {
+
+            if (line === "") {
+                console.log("");
+            } else {
+              console.log(`${String(lineNumber).padStart(6)}  ${line}`);
+                lineNumber++;
+            }
+
+        }
+
+        else {
+            console.log(line);
+        }
+    }
+}