Code review updates

docs/developers/contributing.md

@@ -44,14 +44,14 @@ More information can be found in [gulpfile.js](https://github.com/chartjs/Chart.
 
 ### Image-Based Tests
 
-Some display-related functionality is difficult to test via typical Jasmine unit test asserts. For this functionality, we have image-based tests that assert that the chart is drawn pixel-for-pixel matching an expected image.
+Some display-related functionality is difficult to test via typical Jasmine units. For this reason, we introduced image-based tests ([#3988](https://github.com/chartjs/Chart.js/pull/3988) and [#5777](https://github.com/chartjs/Chart.js/pull/5777)) that assert that a chart is drawn pixel-for-pixel matching an expected image.
 
-Generated charts in image-based tests should be **as minimal as possible** and focus only on tested features to prevent failure if another feature breaks (e.g. disable the title and legend when testing scales).
+Generated charts in image-based tests should be **as minimal as possible** and focus only on the tested feature to prevent failure if another feature breaks (e.g. disable the title and legend when testing scales).
 
 You can create a new image-based test by following the steps below:
-- Create a JS file ([example](https://github.com/chartjs/Chart.js/blob/f7b671006a86201808402c3b6fe2054fe834fd4a/test/fixtures/controller.bubble/radius-scriptable.js)) or JSON file ([example](/chartjs/Chart.js/blob/4b421a50bfa17f73ac7aa8db7d077e674dbc148d/test/fixtures/plugin.filler/fill-line-dataset.json)) that defines chart config and generation options.
-- Add this file in`test/fixtures/{spec.name}/{feature-name}.json`.
-- Add a [describe line](/chartjs/Chart.js/blob/4b421a50bfa17f73ac7aa8db7d077e674dbc148d/test/specs/plugin.filler.tests.js#L10) to the beginning of `specs/{spec.name}.js`.
+- Create a JS file ([example](https://github.com/chartjs/Chart.js/blob/f7b671006a86201808402c3b6fe2054fe834fd4a/test/fixtures/controller.bubble/radius-scriptable.js)) or JSON file ([example](https://github.com/chartjs/Chart.js/blob/4b421a50bfa17f73ac7aa8db7d077e674dbc148d/test/fixtures/plugin.filler/fill-line-dataset.json)) that defines chart config and generation options.
+- Add this file in `test/fixtures/{spec.name}/{feature-name}.json`.
+- Add a [describe line](https://github.com//chartjs/Chart.js/blob/4b421a50bfa17f73ac7aa8db7d077e674dbc148d/test/specs/plugin.filler.tests.js#L10) to the beginning of `specs/{spec.name}.js` if it doesn't exist yet.
 - Set `"debug": true` in the JSON file to prevent the canvas destruction when running tests.
 - Run `gulp unittest --watch --inputs=test/specs/{spec.name}.js`.
 - Click the *"Debug"* button (top/right): a test should fail with the associated canvas visible.
@@ -60,7 +60,7 @@ You can create a new image-based test by following the steps below:
 - Verify test relevancy by changing the feature values *slightly* in the JSON file.
 - Remove `debug: true` from the JSON file.
 
-Tests should pass in both browsers. In general, we've hidden the text for all the image tests since it's quite difficult to get them passing between different browsers. As a result, it is recommended to hide all scales in image-based tests. It is also recommended to disable animations in image-based tests. If tests still do not pass, adjust [`tolerance` and/or `threshold`](https://github.com/chartjs/Chart.js/blob/1ca0ffb5d5b6c2072176fd36fa85a58c483aa434/test/jasmine.matchers.js) at the beginning of the JSON file keeping them **as low as possible**.
+Tests should pass in both browsers. In general, we've hidden the text for all the image tests since it's quite difficult to get them passing between different browsers. As a result, it is recommended to hide all scales in image-based tests. It is also recommended to disable animations. If tests still do not pass, adjust [`tolerance` and/or `threshold`](https://github.com/chartjs/Chart.js/blob/1ca0ffb5d5b6c2072176fd36fa85a58c483aa434/test/jasmine.matchers.js) at the beginning of the JSON file keeping them **as low as possible**.
 
 ## Bugs and Issues