This requires using bash. I find it kind of cheating that git ships bash on Windows so that Windows users can rely on bash for composing git commands. I'm not sure if Windows users are generally that happy about typing bash commands, but I guess nobody really cares what you have to type in as long as it's high in the Google hits for whatever operation you want to perform.
Mercurial's API (i.e. the CLI) makes a point of being usable with powershell and cmd.exe, which I think some Windows users appreciate.
Another way to look at this is that hg needed to bake this into their core, whereas git didn't need to. There is a non-zero cost to all additional code, so leaning on the shell to do work is generally a smart move.
Mercurial's API (i.e. the CLI) makes a point of being usable with powershell and cmd.exe, which I think some Windows users appreciate.