Browserify isn't optimal bundling Chart.js because it adds too many internal wrappers, doesn't handle external/global dependencies and doesn't provide a way to generate ESM builds. Therefore, it seems the right choice to switch to rollup, so move all the build process in `rollup.config.js` and make Gulp to execute `rollup -c`.
We also had to switch to Terser instead of UglifyJS because this last one contains a breaking bug. Note that tests now use the exact same rollup config as our builds (the minified one) to ensure that the bundling and minification steps don't break anything. Finally, replace the `gulp watch` task by `gulp build --watch` to be consistent with the other `unittest` and `docs` watching syntax.
`controllers.*.js` and `core.datasetController.js` are now importable (no more function export), that's why there is so many changes mainly due to one indentation level removed. Split code for `bar/horizontalBar` and `doughnut/pie` in separate files, added a global controllers import (`src/controllers/index.js`) and add tests to check that all dataset controllers are correctly registered under `chart.controllers.{type}`.
- allow options to be updated in-place or as a new object
- re-merge new options and rebuild scales & tooltips
- preserve reference to old scale if id/type not changed
- related tests and new sample also added.
- update document about options update
- update doc and example
For consistency, enable ESLint `one-var` rule to require multiple variable declarations for initialized variables per scope. Uninitialized variables can still be declared together (preferred) or separately.
http://eslint.org/docs/rules/one-var
Properly export helpers and remove dependencies to `Chart.helpers`. Helpers can now be accessed from `src/helpers/index.js` (`var helpers = require('path/to/helpers/index')`, instead of `var helpers = Chart.helpers`).
For consistency with `valueOrDefault`, `valueAtIndexOrDefault` now returns null if `value` (expected array) is null. Also get rid of the superfluous `get` prefix in `getValueOrDefault` and `getValueAtIndexOrDefault`.
In order to take full advantage of the new plugin hooks called before and after a dataset is drawn, all drawing operations must happen on stable meta data, so make sure that transitions are performed before.
In order to simulate real-time chart updates (i.e. horizontal animation), it's necessary to distinguish a removed or added value from a simple update. The dataset controller now hooks array methods that alter the data array length to synchronize metadata accordingly. Also remove the duplicate calls of updateBezierControlPoints() for line and radar charts.
Change the linter in gulp tasks to be consistent with Code Climate results which are based on ESLint using .eslintrc options. However, defaults Code Climate rules are too strict, so turn as warnings the 'complexity' and 'max-statements' rules (other errors has been fixed). Note that the Gulp task name has been changed for `gulp lint`.
This change allows for smaller minified code in the final version, resulting in a smaller file size. Some files had previously used _this, but that has been changed to me to keep consistency throughout the project.
Data controllers should now rarely implement addElements and addElementAndReset but instead should define dataElementType (and optionally datasetElementType). Also remove some dead code (e.g. numBars, colorForNewElement, etc.).
Meta info are now scoped by chart and moved under the dataset._meta map { chart.id -> meta }. Meta for a specific chart (and dataset) can be accessed using chart.getDatasetMeta(datasetIndex) or from the dataset controller using getMeta(). Note that helpers.uid() now generates an int (instead of a string) to make lookups in the _meta map faster.
