implementing a logic that behive as cat command

Author: jamallaqdiem

implement-shell-tools/cat/cat.js

@@ -0,0 +1,40 @@
+import process from "node:process";
+import { promises as fs } from "node:fs";
+
+// THis will give an array without the path to node and to the file.
+const argv = process.argv.slice(2);
+
+//Get line numbers.
+const showNumbers = argv.includes("-n");
+const showNonBlankNumbers = argv.includes("-b");
+
+//filter the - from the array argv as it's a flag.
+const filePaths = argv.filter((arg) => !arg.startsWith("-"));
+let counterLines = 1;
+
+for (const path of filePaths) {
+  try {
+    const content = await fs.readFile(path, "utf-8");
+
+    //split the text at the new line character.
+    const splitLines = content.split("\n");
+
+    splitLines.forEach((line) => {
+      if (showNumbers) {
+        console.log(`${counterLines++}  ${line}`);
+      } else if (showNonBlankNumbers) {
+        // increment and show numbers only if the line is not empty.
+        if (line.trim() !== "") {
+          console.log(`${counterLines++}  ${line}`);
+        } else {
+          // print empty lines
+          console.log(line);
+        }
+      } else {
+        console.log(line);
+      }
+    });
+  } catch (error) {
+    console.log(`Could not read: ${path}`);
+  }
+}