London | 26-SDC-MAR | Jamal Laqdiem | Sprint 3 | Implement Shell Tools

implement-shell-tools/.gitignore

@@ -0,0 +1 @@
+.venv

implement-shell-tools/cat/cat.js

@@ -0,0 +1,44 @@
+import process from "node:process";
+import { promises as fs } from "node:fs";
+
+const argv = process.argv.slice(2);
+
+const showNumbers = argv.includes("-n");
+const showNonBlankNumbers = argv.includes("-b");
+
+const filePaths = argv.filter((arg) => !arg.startsWith("-"));
+
+const flagsUsed = argv.filter((arg) => arg.startsWith("-"));
+const supportedFlags = ["-n", "-b"];
+for (const flag of flagsUsed) {
+  if (!supportedFlags.includes(flag)) {
+    console.error(`Invalid option: please try "-n or "-b"`);
+    process.exit(1);
+  }
+}
+
+let counterLines = 1;
+
+for (const path of filePaths) {
+  try {
+    const content = await fs.readFile(path, "utf-8");
+.
+    const splitLines = content.split("\n");   
+
+    splitLines.forEach((line) => {
+      let prefix = "";
+
+      if (showNonBlankNumbers) {
+        if (line.trim() !== "") {
+          prefix = `${counterLines++}  `;
+        }
+      } else if (showNumbers) {
+        prefix = `${counterLines++}  `;
+      }
+      console.log(`${prefix}${line}`);
+    });
+  } catch (error) {
+    console.error(`Error ${path}: ${error.message}`);
+    process.exit(1);
+  }
+}

implement-shell-tools/ls/ls.js

@@ -0,0 +1,27 @@
+import fs from "node:fs";
+import process from "node:process";
+
+const argv = process.argv.slice(2);
+
+const filePaths = argv.filter((arg) => !arg.startsWith("-"));
+const showHiddenFiles = argv.includes("-a");
+
+if (filePaths.length > 1) {
+  console.error("Error: This version only supports one directory path a time.");
+  process.exit(1);
+}
+
+const target = filePaths[0] || ".";
+
+const files = fs.readdirSync(target);
+
+let filteredFIles = files;
+if (!showHiddenFiles) {
+  filteredFIles = files.filter((file) => !file.startsWith("."));
+} else {
+  filteredFIles = [".", "..", ...files];
+}
+
+filteredFIles.forEach((file) => {
+  console.log(file);
+});

implement-shell-tools/wc/wc.js

@@ -0,0 +1,67 @@
+import process, { exit } from "node:process";
+import fs from "node:fs";
+
+const argv = process.argv.slice(2);
+
+let showWords = argv.includes("-w");
+let showLines = argv.includes("-l");
+let showBytes = argv.includes("-c");
+let showCharacters = argv.includes("-m");
+
+const filePaths = argv.filter((arg) => !arg.startsWith("-"));
+// if no flags enable all.
+if (!showLines && !showCharacters && !showWords && !showBytes) {
+  showLines = true;
+  showCharacters = true;
+  showWords = true;
+  showBytes = true;
+}
+
+if (filePaths.length === 0) {
+  console.error("PLease provide a file path");
+  process.exit(1);
+}
+
+let totalLines = 0;
+let totalWords = 0;
+let totalBytes = 0;
+let totalChars = 0;
+
+filePaths.forEach((filePath) => {
+  try {
+    const content = fs.readFileSync(filePath, "utf-8");
+    const lineArray = content.split("\n");
+    if (content.endsWith("\n")) lineArray.pop(); 
+    const lines = lineArray.length;
+
+    const words = content.trim().split(/\s+/).filter((word) => word != "").length;
+    const bytes = Buffer.byteLength(content);
+    const characters = content.length;
+
+    totalLines += lines;
+    totalWords += words;
+    totalBytes += bytes;
+    totalChars += characters;
+
+    let output = "";
+    if (showLines)   output += lines.toString().padStart(8);
+    if (showWords)   output += words.toString().padStart(8);
+    if (showBytes)   output += bytes.toString().padStart(8);
+    if (showCharacters) output += characters.toString().padStart(8)
+
+    console.log(`${output} ${filePath}`); 
+  } catch(error) {
+    console.error(`Error reading ${filePath}: ${error.message}`);
+  }
+}); 
+
+if (filePaths.length > 1) {
+  let totalOutput = "";
+  if (showLines)  totalOutput += `${totalLines.toString().padStart(8)}`;
+  if (showWords)  totalOutput += `${totalWords.toString().padStart(8)}`;
+  if (showBytes)  totalOutput += `${totalBytes.toString().padStart(8)}`;
+  if (showCharacters) totalOutput += `${totalChars.toString().padStart(8)}`;
+
+  console.log(`${totalOutput} total`);
+}
+