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// Test for Architecture 1

fetch = spy().andMockWith(function (args) {
    // pattern matching and pretend games
})
assertSpyStuff
assertMoreSpyStuff
assertMoreSpyStuff

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// Test for Architecture 2

assert.deepEqual(
    buildRequest(x, y, z),
    expectedRequest
)

assert.deepEqual(
    parseResponse(response),
    expectedParsedResponse

mheiber

Are Mocks a Smell?

It's hard to write unit tests that are worth the costs our employers pay for them. I'll share two mostly-made-up diagrams then use them to justify writing code as data transformation.

Factual Diagrams

There are four types of code:

**Diagram 1: Types of Code**

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	MobX observable	Rx Observable
has to do with things changing	yes	yes
"reactive"	yes	yes

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	MobX observable	Rx Observable
common use case	facilitating updating a UI when data changes	composing frequently-updated data from multiple sources and/or implementing a lot of timing logic
better name is	"sneaky KVO"	"composable streams"
very similar to	reactive data in Meteor and Vue	Node streams if Node streams were always in object mode and had things like through2 and multipipe built in
implementation in JS requires

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nnoremap <leader><space> :noh<return>
nnoremap <leader><leader> :b#<CR>
nnoremap <leader>S :source ~/.vimrc<CR>
nnoremap <leader>g :e ~/.vimrc<CR>
nnoremap <right> <C-w>10>
nnoremap <left> <C-w>10<
nnoremap <leader>1 :bp<Cr>
nnoremap <leader>2 :bp<Cr>
nnoremap <leader>] @:

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:tnoremap <Esc> <C-\><C-n>
:tnoremap jj <C-\><C-n>
:tnoremap <C-w><C-w> <C-\><C-n><C-w><C-w>
:source ~/.vimrc
au TermOpen * setlocal nonumber norelativenumber
:nnoremap <leader>e <C-w><C-w>pa


Plugin 'tpope/vim-surround'
Plugin 'tpope/vim-commentary'

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class A {
    #foo;
    #bar;
    method() {
        class B {
            #foo;
            methodNested(a) {
                a.#foo;  // error: shadowed
                a.#bar; //  OK
            }

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Three error cases for private name semantic errors:

1. shadowing (the nested classes case). See also suggested error message.
2. accessibility violation
3. name not found

(1) and (2) are special cases of (3)

Confusing note on terminology: in the semantics, '#foo' is the description for a private name, what a Muggle would call a "spelling" and a philosophyer would call an "orthography." From a semantic point of view, the private name itself (#foo) is unforgeable and cannot be written down, even thought it's clear exactly where the private name node in the syntax is.

Rough algorithm for generating the most accurate error message for leftHandSide.#foo:

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const main = () => {
    const x = 2
    const y = 3

    ;[1, 2, 3].forEach(v => {
        console.log(v, y)
    })

    console.log(x, y)
}