html - How flexbox calculates flex-item's width if no flex-basis or width are set?

Question

I want to understand how flexbox calculates final flex-item's width when no explicit value is set for flex-basis, width, min-width or max-width properties are set. In other words, how flexbox calculates flex-item's width based solely on content?

Here is an example code (available on codepen):

.container {
  display: flex;
  width: 600px;
}

.container div {
  outline: 1px dotted black;
}

<div class="container">
  <div>Lorem ipsum dolor sit amet consectetur adipisicing elit. Fuga aspernatur suscipit aliquam beatae vitae harum, eius expedita quidem incidunt velit!</div>
  <div>Lorem ipsum dolor sit, amet consectetur adipisicing elit. Error ad natus dolores harum, ex fuga voluptates dignissimos possimus saepe officia.</div>
</div>

Answer 1

For this particular case you need to conisder the default shrink effect set by flex-shrink which has a default value of 1. Initially your element will overflow like below:

$('div').each(function() {
 console.log($(this).width());
})

.container {
  display: flex;
  width: 600px;
}

.container div {
  outline: 1px dotted black;
  flex-shrink:0;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div class="container">
  <div>Lorem ipsum dolor sit amet consectetur adipisicing elit. Fuga aspernatur suscipit aliquam beatae vitae harum, eius expedita quidem incidunt velit! 123456789</div>
  <div>Lorem ipsum dolor sit amet consectetur adipisicing elit. Fuga aspernatur suscipit aliquam beatae vitae harum, eius expedita quidem incidunt velit!</div>
</div>