Bookmarklet: Compare GitHub commit with Master

Bookmarklet - Compare GitHub commit with master branch.md

Usage

1. Create a new bookmark in your bookmarks bar with the following contents:

javascript: (function(){
            let location = window.location.href;
            let validatorRegex = /https:\/\/github.com\/[a-z][a-zA-z0-9\-\_]+\/[a-z][a-zA-z0-9\-\_]+\/commit\/[a-f0-9]+/g;
            let match = location.match(validatorRegex);
            if(!match){
                console.log('No match. You must be viewing a commit.');
                alert('Use this bookmarklet when viewing a commit.');
            }
            else{
                console.log('Location matches a commit - redirecting to diff view.');        
                let repoLocationRegex =  /https:\/\/github.com\/[a-z][a-zA-z0-9\-\_]+\/[a-z][a-zA-z0-9\-\_]+/g;
                let commitRegex = /\/commit\/[a-f0-9]+/g;
                let repoLocation = location.match(repoLocationRegex)[0];
                let commitId = location.match(commitRegex)[0].slice(8);
                console.log(repoLocation);
                console.log(commitId);
                let compareLocation = `${repoLocation}/compare/${commitId}...master `;
                window.location.href = compareLocation;
            }})();

2. Browse to a commit you wish to compare with its current master branch, and press the bookmarklet.

script.js

(function(){
            let location = window.location.href;
            let validatorRegex = /https:\/\/github.com\/[a-z][a-zA-z0-9\-\_]+\/[a-z][a-zA-z0-9\-\_]+\/commit\/[a-f0-9]+/g;
            let match = location.match(validatorRegex);
            if(!match){
                console.log('No match. You must be viewing a commit.');
                alert('Use this bookmarklet when viewing a commit.');
            }
            else{
                console.log('Location matches a commit - redirecting to diff view.');        
                let repoLocationRegex =  /https:\/\/github.com\/[a-z][a-zA-z0-9\-\_]+\/[a-z][a-zA-z0-9\-\_]+/g;
                let commitRegex = /\/commit\/[a-f0-9]+/g;
                let repoLocation = location.match(repoLocationRegex)[0];
                let commitId = location.match(commitRegex)[0].slice(8);
                console.log(repoLocation);
                console.log(commitId);
                let compareLocation = `${repoLocation}/compare/${commitId}...master `;
                window.location.href = compareLocation;
            }})();

Thanks, this is useful. I had to change master to main for it to work.

javascript: (function(){
            let location = window.location.href;
            let validatorRegex = /https:\/\/github.com\/[a-z][a-zA-z0-9\-\_]+\/[a-z][a-zA-z0-9\-\_]+\/commit\/[a-f0-9]+/g;
            let match = location.match(validatorRegex);
            if(!match){
                console.log('No match. You must be viewing a commit.');
                alert('Use this bookmarklet when viewing a commit.');
            }
            else{
                console.log('Location matches a commit - redirecting to diff view.');        
                let repoLocationRegex =  /https:\/\/github.com\/[a-z][a-zA-z0-9\-\_]+\/[a-z][a-zA-z0-9\-\_]+/g;
                let commitRegex = /\/commit\/[a-f0-9]+/g;
                let repoLocation = location.match(repoLocationRegex)[0];
                let commitId = location.match(commitRegex)[0].slice(8);
                console.log(repoLocation);
                console.log(commitId);
                let compareLocation = `${repoLocation}/compare/${commitId}...main`;
                window.location.href = compareLocation;
            }})();