I've noticed that if I run the command with just width and no height, width is ignored.

From line 41: if (program.w && program.h) await page.setViewport({width: Number(program.w), height: Number(program.h)})

If I run it with a specified width, and height 0, I do get the specified width.
So the user can get around this but a nice addition might be to set h to 0 if it's unset.

Maybe something like this

diff --git a/index.js b/index.js
index 40f5b02..cb7b821 100755
--- a/index.js
+++ b/index.js
@@ -38,7 +38,8 @@ console.log(fullPage);
     const browser = await puppeteer.launch()
     const page = await browser.newPage()
     const d = new Date()
-    if (program.w && program.h) await page.setViewport({width: Number(program.w), height: Number(program.h)})
+    const height = !program.h?0:program.h;
+    if (program.w && height) await page.setViewport({width: Number(program.w), height: Number(height)})
     if (program.emulate) await page.emulate(devices[program.emulate]);
     await page.goto(urlvalue)
     const title = await page.title()

Add the possibility to indicate a parameter to wait to take the screenshot, or even be able to indicate which element of the DOM has to be visible.

If you load the url https://es.hboespana.com/movies/overview/3b1f95c-00fe50831f9, screenshot is HBO icon because the page is loading.

I ran:

screenshoteer --url  https://news.ycombinator.com/item\?id\=18598672 --el ".fatitem" --pdf

Great, great work on screenshoteer! I've been looking for a good scriptable solution to screen shots for a long time.

One question: what, if any, strategies might there be to get screenshoteer to work with URLs that require authentication beyond basic http auth?

maybe add --waitUntil="networkidle2" parameter

await page.goto('https://news.ycombinator.com', {waitUntil: 'networkidle2'});

waitUntil can be either:
load - consider navigation to be finished when the load event is fired.
domcontentloaded - consider navigation to be finished when the DOMContentLoaded event is fired.
networkidle0 - consider navigation to be finished when there are no more than 0 network connections for at least 500 ms.
networkidle2 - consider navigation to be finished when there are no more than 2 network connections for at least 500 ms.

You accidentally committed your .DS_Store. It's in the .gitignore but you must have committed it prior to adding it there. Depending on deployment process, this could be a security issue. https://www.intego.com/mac-security-blog/possible-security-issue-involving-ds_store-files-on-web-servers/

Can send out a PR let me know. Azure Pipelines offers free CI/CD on all three platforms.

I see that #4 was closed.

But we should write some small tests to test on Travis CI an so on and catch regressions / bugs.

Would love to be able to do:

screenshoteer --url=./test-output.html

Command:
screenshoteer --url https://vk.se
OS:
Windows 10

output:
https://vk.se true (node:32328) UnhandledPromiseRejectionWarning: Error: ENOENT: no such file or directory, open 'C:\Users\marcu\Desktop\Västerbottens-Kuriren | Västerbottens nyhetsportal undefined 1543958297443.png' -- ASYNC -- at Page.<anonymous> (C:\Users\marcu\AppData\Roaming\npm\node_modules\screenshoteer\node_modules\puppeteer\lib\helper.js:144:27) at C:\Users\marcu\AppData\Roaming\npm\node_modules\screenshoteer\index.js:45:16 at <anonymous> at process._tickCallback (internal/process/next_tick.js:188:7) (node:32328) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1) (node:32328) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

this character "|" you can not have in a file / folder name on windows