Complete implementing ls shell-tools.

Author: Fithi-Teklom

implement-shell-tools/ls/ls.js

@@ -0,0 +1,77 @@
+const fs = require("fs");
+const pathModule = require("path");
+
+const args = process.argv.slice(2);
+
+let mode = "normal";
+let showHidden = false;
+let paths = [];
+
+for (const arg of args) {
+  if (arg === "-1") {
+    mode = "onePerLine";
+  } else if (arg === "-a") {
+    showHidden = true;
+  } else {
+    paths.push(arg);
+  }
+}
+
+if (paths.length === 0) {
+  paths.push(".");
+}
+
+function listDirectory(dir) {
+  let items = fs.readdirSync(dir);
+
+  if (showHidden) {
+    items.unshift(".", "..");
+  } else {
+    items = items.filter(item => !item.startsWith("."));
+  }
+
+  if (mode === "onePerLine") {
+    items.forEach(item => console.log(item));
+  } else {
+    console.log(items.join("  "));
+  }
+}
+
+function expandWildcard(input) {
+  if (!input.includes("*")) {
+    return [input];
+  }
+  const dir = pathModule.dirname(input);
+  const pattern = pathModule.basename(input);
+  const files = fs.readdirSync(dir);
+
+  return files
+    .filter(file => {
+      if (pattern === "*") {
+        return showHidden || !file.startsWith(".");
+      }
+
+      return file === pattern;
+    })
+    .map(file => pathModule.join(dir, file));
+}
+
+for (const originalPath of paths) {
+
+  const expandedPaths = expandWildcard(originalPath);
+
+  for (const currentPath of expandedPaths) {
+
+    const info = fs.statSync(currentPath);
+
+    if (info.isDirectory()) {
+      listDirectory(currentPath);
+    }
+
+    else if (info.isFile()) {
+      console.log(pathModule.basename(currentPath));
+    }
+
+  }
+
+}