Manchester| 26-SDC-Jun | Fithi Teklom | Sprint 3 | Implement-shell-tools

implement-shell-tools/cat/cat.js

@@ -0,0 +1,43 @@
+const fs = require("fs");
+
+const args = process.argv.slice(2);
+
+let mode = "normal";
+let files = [];
+
+if (args[0] === "-n") {
+  mode = "number";
+  files = args.slice(1);
+} else if (args[0] === "-b") {
+  mode = "numberNonEmpty";
+  files = args.slice(1);
+} else {
+  files = args;
+}
+
+let lineNum = 1;
+
+for (const file of files) {
+  const content = fs.readFileSync(file, "utf8");
+
+  const lines = content.replace(/\n$/, "").split("\n");
+
+  if (mode === "normal") {
+    console.log(content);
+    continue;
+  }
+
+  for (const line of lines) {
+    if (mode === "number") {
+      console.log(`${String(lineNum).padStart(6)}  ${line}`);
+      lineNum++;
+    } else if (mode === "numberNonEmpty") {
+      if (line === "") {
+        console.log("");
+      } else {
+        console.log(`${String(lineNum).padStart(6)}  ${line}`);
+        lineNum++;
+      }
+    }
+  }
+}

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));
+    }
+
+  }
+
+}

implement-shell-tools/wc/wc.js

@@ -0,0 +1,109 @@
+const fs = require("fs");
+const path = require("path");
+
+const args = process.argv.slice(2);
+
+let countLines = false;
+let countWords = false;
+let countBytes = false;
+
+let files = [];
+
+for (const arg of args) {
+  if (arg === "-l") {
+    countLines = true;
+  } else if (arg === "-w") {
+    countWords = true;
+  } else if (arg === "-c") {
+    countBytes = true;
+  } else {
+    files.push(arg);
+  }
+}
+
+function expandWildcard(filePath) {
+  if (!filePath.includes("*")) {
+    return [filePath];
+  }
+
+  const dir = path.dirname(filePath);
+  const files = fs.readdirSync(dir);
+
+  return files.map(file => path.join(dir, file));
+}
+
+function getStats(filename) {
+
+  const content = fs.readFileSync(filename, "utf8");
+
+  const lines = content.split("\n").length - 1;
+
+  const words = content
+    .trim()
+    .split(/\s+/)
+    .filter(word => word.length > 0)
+    .length;
+
+  const bytes = fs.statSync(filename).size;
+
+  return {
+    lines,
+    words,
+    bytes
+  };
+}
+
+function printResult(stats, filename, showFilename = true) {
+
+  let output = [];
+
+  if (!countLines && !countWords && !countBytes) {
+    output.push(stats.lines);
+    output.push(stats.words);
+    output.push(stats.bytes);
+  } else {
+    if (countLines) {
+      output.push(stats.lines);
+    }
+
+    if (countWords) {
+      output.push(stats.words);
+    }
+
+    if (countBytes) {
+      output.push(stats.bytes);
+    }
+  }
+
+  if (showFilename) {
+    output.push(filename);
+  }
+
+  console.log(output.join(" "));
+}
+
+let allFiles = [];
+
+for (const file of files) {
+  allFiles.push(...expandWildcard(file));
+}
+
+let total = {
+  lines: 0,
+  words: 0,
+  bytes: 0
+};
+
+for (const file of allFiles) {
+
+  const stats = getStats(file);
+
+  total.lines += stats.lines;
+  total.words += stats.words;
+  total.bytes += stats.bytes;
+
+  printResult(stats, file);
+}
+if (allFiles.length > 1) {
+  printResult(total, "total");
+}