cat review

Author: delmorallopez

implement-shell-tools/cat/script-01.js

@@ -1,36 +1,66 @@
+#!/usr/bin/env node
 import { program } from "commander";
 import { promises as fs } from "node:fs";
-//import process from "node:process";
 
 // Setup CLI with commander
 program
     .name("count-containing-words")
     .description("Counts words in a file that contain a particular character")
     .option("-c, --char <char>", "The character to search for", "e")
-    .argument("<path>", "The file path to process");
+    .option("-n, --number", "Number all lines like cat -n")
+    .option("-b, --number-nonblank", "Number only non-blank lines like cat -b")
+    .argument("<path...>", "The file path(s) to process"); // allow multiple files
 
-// Parse CLI arguments    
 program.parse();
 const argv = program.args;
 
 // Validate arguments
-if (argv.length != 1) {
-    console.error(`Expected exactly 1 argument (a path) to be passed but got ${argv.length}.`);
+if (argv.length === 0) {
+    console.error(`Expected at least 1 file path to be passed but got ${argv.length}.`);
     process.exit(1);
 }
 
+const { char, number, numberNonblank } = program.opts();
+let globalLineCounter = 1;
 
-const path = argv[0];
-const char = program.opts().char;
+for (const path of argv) {
+    let content;
+    try {
+        content = await fs.readFile(path, "utf-8");
+    } catch (err) {
+        console.error(`Cannot read file ${path}: ${err.message}`);
+        continue;
+    }
 
-// Read file content
-const content = await fs.readFile(path, "utf-8");
-console.log("content",content)
+    // Split file into lines
+    let lines = content.split("\n");
 
-// Count words containing the character
-const countOfWordsContainingChar = content
-  .split(" ")
-  .filter((word) => word.includes(char))
-  .length;
-console.log(countOfWordsContainingChar);
+    // Remove last empty line if file ends with a newline
+    if (lines[lines.length - 1] === "") {
+        lines = lines.slice(0, -1);
+    }
 
+    // Process each line
+    for (let line of lines) {
+        // Count words containing the specified character in this line
+        const countInLine = line
+            .split(" ")
+            .filter(word => word.includes(char))
+            .length;
+
+        // Determine line numbering
+        if (number) {
+            console.log(`${String(globalLineCounter).padStart(6)}\t${line}  [${countInLine}]`);
+            globalLineCounter++;
+        } else if (numberNonblank) {
+            if (line.trim().length > 0) {
+                console.log(`${String(globalLineCounter).padStart(6)}\t${line}  [${countInLine}]`);
+                globalLineCounter++;
+            } else {
+                console.log(`${line}  [${countInLine}]`);
+            }
+        } else {
+            console.log(`${line}  [${countInLine}]`);
+        }
+    }
+}