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usb.on is not a function

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
45/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Quiet
Tech stack
nodejs
Domain
embedded-iot

Research direction

Start at node_modules/escpos-usb/index.js line 52, where the USB constructor calls usb.on, and compare that entry point with the Node v18.15.0 dependency setup in the report. Reproduce the provided index.js example and trace why usb lacks on; done means the constructor no longer throws this error and the printer example can proceed to device.open().

Written by the indexing model from the issue text.

Description

Node v18.15.0

"dependencies": {
"escpos": "^3.0.0-alpha.6",
"escpos-usb": "^3.0.0-alpha.4"
}

Code:

const escpos = require('escpos');
escpos.USB = require('escpos-usb');

const device = new escpos.USB(0x2BDF, 0x0280);
const printer = new escpos.Printer(device);

device.open(function (error) {
if (error) {
console.error('Error opening USB device:', error);
return;
}

printer
    .font('a')
    .align('ct')
    .style('bu')
    .size(1, 1)
    .text('Your Store Name')
    .text('----------------')
    .align('lt')
    .text('Item 1       $10.00')
    .text('Item 2        $7.50')
    .text('----------------')
    .align('rt')
    .text('Total:      $17.50')
    .cut()
    .close();

});

Error:
C:\Users\juan\Desktop\test-printer\node_modules\escpos-usb\index.js:52
usb.on('detach', function(device){
^

TypeError: usb.on is not a function
at new USB (C:\Users\x\Desktop\test-printer\node_modules\escpos-usb\index.js:52:7)
at Object. (C:\Users\x\Desktop\test-printer\index.js:5:16)
at Module._compile (node:internal/modules/cjs/loader:1254:14)
at Module._extensions..js (node:internal/modules/cjs/loader:1308:10)
at Module.load (node:internal/modules/cjs/loader:1117:32)
at Module._load (node:internal/modules/cjs/loader:958:12)
at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:81:12)
at node:internal/main/run_main_module:23:47

Dominant language
TypeScript
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