First task

src/cli/args.js

@@ -1,5 +1,13 @@
 const parseArgs = () => {
-    // Write your code here 
+  const args = process.argv.slice(2);
+
+  for (let i = 0, len = args.length; i < len; i++) {
+      if(args[i].startsWith("--")) {
+        console.log(args[i].slice(2) + ' is ' + args[i + 1]);
+      }
+  }
 };
 
-parseArgs();
+parseArgs();
+
+// args.js - implement function that parses command line arguments (given in format --propName value --prop2Name value2, you don't need to validate it) and prints them to the console in the format propName is value, prop2Name is value2

src/cli/env.js

@@ -1,5 +1,15 @@
+const env_variables = process.env;
+
+const result = [];
+
 const parseEnv = () => {
-    // Write your code here 
+    for (const key in env_variables) {
+        if (key.startsWith("RSS_")) {
+            result.push(`${key}: ${env_variables[key]}`);
+        }
+    }
+    console.log(result);
+    return result;
 };
 
 parseEnv();

src/fs/copy.js

@@ -1,5 +1,34 @@
-const copy = async () => {
-    // Write your code here 
+import fs from 'fs';
+
+const checkIfDirExists = async (dirPath) => {
+    try {
+        await fs.promises.access(dirPath, fs.constants.F_OK);
+        return true;
+    } catch (err) {
+        return false;
+    }
+
+}
+
+
+const copy = async (dest_dir, copy_name) => {
+
+    const existsDestFolder = await checkIfDirExists(dest_dir);
+    const existsCopyFolder = await checkIfDirExists(copy_name);
+
+    if (!existsDestFolder) {
+        throw new Error(`Could not find ${dest_dir}`);
+    }
+    if (existsCopyFolder) {
+        throw new Error(` ${copy_name} already exists`);
+    }
+    fs.cp(dest_dir, copy_name, {recursive: true}, (err) => {
+        if (err) throw err.message;
+    })
 };
 
-await copy();
+
+await copy('files', 'files_copy');
+
+
+// copy.js - implement function that copies folder files files with all its content into folder files_copy at the same level (if files folder doesn't exist or files_copy has already been created Error with message FS operation failed must be thrown)

src/fs/create.js

@@ -1,5 +1,22 @@
+import fs  from 'fs';
+
+const content = 'I am fresh and young :)'
+
 const create = async () => {
-    // Write your code here 
-};
+    fs.access('./files/fresh.tsx', fs.constants.F_OK, (err) => {
+        if (err) {
+            return fs.writeFile('./files/fresh.tsx', content, err => {
+                if (err) return console.log(err);
+            })
+        } else {
+            console.log('File or directory exists');
+        }
+    });
+}
+
+await create();
+
+
+//TODO: add throw
 
-await create();
+// create.js - implement function that creates new file fresh.txt with content I am fresh and young inside of the files folder (if file already exists Error with message FS operation failed must be thrown)

src/fs/delete.js

@@ -1,5 +1,14 @@
-const remove = async () => {
-    // Write your code here 
+import fs from 'fs';
+
+const filePath = './files/fileToRemove.txt'
+
+const remove = async (filePath) => {
+
+    fs.unlink(filePath, (err) => {
+       if (err) throw err.message;
+   })
 };
 
-await remove();
+await remove(filePath);
+
+// delete.js - implement function that deletes file fileToRemove.txt (if there's no file fileToRemove.txt Error with message FS operation failed must be thrown)

src/fs/list.js

@@ -1,5 +1,16 @@
+import fs from 'fs';
+const path = './files';
+
 const list = async () => {
-    // Write your code here 
+  fs.readdir(path, (err, files) => {
+      if (err) {
+          throw err.message;
+      }
+      console.log(files);
+  })
 };
 
-await list();
+await list();
+
+
+// list.js - implement function that prints array of all filenames from files folder into console (if files folder doesn't exists Error with message FS operation failed must be thrown)

src/fs/read.js

@@ -1,5 +1,26 @@
+import path from 'path';
+import fs from 'fs';
+
+
 const read = async () => {
+
+    const filePath = path.join(process.cwd(), './files/fileToRead.txt');
+
+    fs.readFile(filePath, 'utf8', (err, data) => {
+        if(err) {
+            if(err.code === 'ENOENT') {
+                throw new Error(err.message);
+            }
+            else {
+                throw err;
+            }
+        }
+        console.log(data);
+    })
     // Write your code here 
 };
 
-await read();
+await read();
+
+
+// read.js - implement function that prints content of the fileToRead.txt into console (if there's no file fileToRead.txt Error with message FS operation failed must be thrown)

src/fs/rename.js

@@ -1,5 +1,30 @@
-const rename = async () => {
-    // Write your code here 
+import fs from 'fs';
+
+const checkIfFileExists = async (file_name) => {
+    try {
+        await fs.promises.access(file_name, fs.constants.R_OK);
+        return true;
+    }
+    catch (e) {
+        return false;
+    }
+
+}
+
+
+const rename = async (current_name, new_name) => {
+    const exists = checkIfFileExists(current_name);
+    if (!exists) {
+        throw new Error(`File ${current_name} does not exist`);
+    }
+
+    fs.rename(current_name, new_name, (err) => {
+        if (err) {
+            throw err.message;
+        }
+    })
 };
 
-await rename();
+await rename('./files/wrongFilename.txt',  './files/properFilename.md');
+
+// rename.js - implement function that renames file wrongFilename.txt to properFilename with extension .md (if there's no file wrongFilename.txt or properFilename.md already exists Error with message FS operation failed must be thrown)

src/hash/calcHash.js

@@ -2,4 +2,6 @@ const calculateHash = async () => {
     // Write your code here 
 };
 
-await calculateHash();
+await calculateHash();
+
+// calcHash.js - implement function that calculates SHA256 hash for file fileToCalculateHashFor.txt and logs it into console as hex using Streams API

src/modules/files/c.cjs

@@ -1 +1 @@
-console.log('Hello from c.cjs!');
+console.log('Hello from c.js!');