Using Flexbox and text ellipsis together

Another day I was asked to build a table containing a list of files uploaded by the users. Imagine a table similar to the list of files in Finder:

The second item of the table is mobile-phone-screenshot-long-fine-name.png, however the column is not big enough to show the complete filename. Instead, we see mobile-phone-sc...g-fine-name.png. In this project, we decided to cut part of the end of the filename and keeping the extension, as shown above:

HTML markup:

<div className="filename">
  <span className="filename__base"
    >this-file-has-a-really-really-really-long-filename.</span
  >
  <span className="filename__extension">pdf</span>
</div>

CSS:

.filename {
  display: flex;
  min-width: 0;
}
 
.filename__base {
  text-overflow: ellipsis;
  white-space: nowrap;
  overflow: hidden;
}
 
.filename__extension {
  flex-shrink: 0;
}

The ellipsis effect can be done by combining text-overflow, white-space and overflow properties, however, we still need to figure out the relation between the filename base and its parent, which also contains the file extension.

The trick is using the property min-width, as covered in this pen by AJ Foster ↗︎ and CSS Tricks ↗︎. From the Flexbox spec ↗︎:

Note: The auto keyword, representing an automatic minimum size, is the new initial value of the min-width and min-height properties. The keyword was previously defined in this specification, but is now defined in the CSS Sizing module.

...

In general, the content-based minimum size of a flex item is the smaller of its content size suggestion and its specified size suggestion.

By using min-width: 0, we are changing the minimum size of the flexbox container, which will resize the child elements of the container that don't use the flex-shrink attribute. Since the filename base element has the text-overflow, white-space and overflow properties, the ellipsis will be rendered properly.

The full example is available in this Codepen ↗︎: