console.diff()

Chrome devtools extension intended to display result of deep in-memory object comparisons with the help of dedicated console commands.

Features

• compare objects from multiple tabs and/or between page reloads
• function code included in comparison result in form of a string, may help to see if it was altered
• document, dom-elements and other non-serializable objects are filtered-out from the results
• self recurring references displayed only once, the rest of occurrences are filtered-out

API

console.diff(left, right);  // compare left and right
console.diff(next);         // shorthand of diffPush while single argumented
console.diffLeft(left);     // update object on the left side only
console.diffRight(right);   // update object on the right side only
console.diffPush(next);     // shifts sides, right becomes left, next becomes right

Usage basics

Historically, left side represents the old state and right side the new state.

• Things that are present on the left side but missing on the right side are colour-coded as red (old).
• Things that are missing on the left side but present on the right side are colour-coded as green (new).

To track changes of the same variable in timed manner you can push it with diffPush or diff with a single argument, that will shift objects from right to left, showing differences with previous push state.

How it works

• jsdiff-devtools registers devtools panel
  • injects console commands that send data to jsdiff-proxy
  • injects jsdiff-proxy to farther communicate objects to the extension's jsdiff-background
• when console.diff command invoked
  • argument/s are cloned in a suitable form for sending between different window contexts and sent to jsdiff-proxy
  • jsdiff-proxy catches the data and sends it to the jsdiff-background where it is stored for future consuming
• when jsdiff-panel is mounted (visible in devtools) it listens to data expected to come from the jsdiff-background and displays it

Screenshot

Based on

• jsondiffpatch by Benjamín Eidelman
• vuejs by Evan You