Follow #23328
The improvements:
1. The `contains` functions are covered by tests
2. The inconsistent behavior of `containGeneric` is replaced by
`StringUtils.Contains` and `SliceUtils.Contains`
3. In the future we can move more help functions into XxxUtils to
simplify the `helper.go` and reduce unnecessary global functions.
FAQ:
1. Why it's called `StringUtils.Contains` but not `strings.Contains`
like Golang?
Because our `StringUtils` is not Golang's `strings` package. There will
be our own string functions.
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Co-authored-by: silverwind <me@silverwind.io>
One of the steps in #23328
Before there were 3 different but similar functions: dict/Dict/mergeinto
The code was just copied & pasted, no test.
This PR defines a new stable `dict` function, it covers all the 3 old
functions behaviors, only +160 -171
Future developers do not need to think about or guess the different dict
functions, just use one: `dict`
Why use `dict` but not `Dict`? Because there are far more `dict` than
`Dict` in code already ......
