[Question] For testing, override rules and restore previous rules about di-ninja

[ernsheong]

So I guess the DIY way is something like:

const rules = {...};

di.addRules(rules);

di.resetRules = function() {
  di.addRules(rules);
};

[devthejo]

You can do this way, but you have to disable the ruleCache first

di.config('ruleCache', false)

ruleCache is enabled by default for optimization because the main expected usage is only one main call to addRules by application and the processing of rules is the main computing cost of Di-Ninja.

There is another point, the rules are apllied in cascade in a deep merging process (a little like CSS), and in your first call to di.addRules, the override will be on rulesDefault, and on the second call, from the other rules that you have defined, there will be no difference if you explicit all options of a rule but else this can lead to unexpected results.

A workaround is to completely override the rules object like this

di.resetRules = function() {
  di.rules = {} // hard reset
  di.addRules(rules)
}

it's a bit hacky and if you call resetRules when there is some async rule procressing, you'll make a knot bag.

Another approach would be to explicit all options of a rule on reset

di.resetRules = function() {
  const explicitRules = {}

  Object.keys(rules).forEach(key=>{
    const explicitRule = {}
    di.mergeRule(explicitRule, di.rulesDefault)
    di.mergeRule(explicitRule, rules[key])
    explicitRules[key] = explicitRule
  })

  di.addRules(explicitRules)
}

But I think the better way is to instantiate another di container, after all, this is not a damn singleton ;), so you can just

import container from 'di-ninja'

const di = container({
  rules,
})
/*
exactly the same as
const di = container()
di.addRules(rules)
*/

const di2 = container({
  rules2,
})

[ernsheong]

The separate di container seems the most promising. Thanks for the tip!

Other than that, the caching behavior seems like a gotcha. But not undocumented :)

[devthejo]

You're right for the gotcha of caching, this desserve a more explicit warning in documentation, maybe in rules section, feel free to make a pull request for this.
I have to add precision that you have this problem only if you call di.addRules after di.get on the rule

// no cache no problem
di.addRules({
  'A': { /*...*/ }
})
di.addRules({
  'A': { /*...*/ }
})

di.get('A')

// cache problem
di.addRules({
  'A': { /*...*/ }
})

// this call build rule and cache it
di.get('A')

// this is no more effective
di.addRules({
  'A': { /*...*/ }
})
/*
  maybe this should send a warning
  I'll investigate into this, and I'll add a console warning
  PR is welcome too
*/

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.