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1'use strict';
2const chainRegistry = new WeakMap();
3
4function startChain(name, call, defaults) {
5 const fn = (...args) => {
6 call({...defaults}, args);
7 };
8
9 Object.defineProperty(fn, 'name', {value: name});
10 chainRegistry.set(fn, {call, defaults, fullName: name});
11 return fn;
12}
13
14function extendChain(prev, name, flag) {
15 if (!flag) {
16 flag = name;
17 }
18
19 const fn = (...args) => {
20 callWithFlag(prev, flag, args);
21 };
22
23 const fullName = `${chainRegistry.get(prev).fullName}.${name}`;
24 Object.defineProperty(fn, 'name', {value: fullName});
25 prev[name] = fn;
26
27 chainRegistry.set(fn, {flag, fullName, prev});
28 return fn;
29}
30
31function callWithFlag(prev, flag, args) {
32 const combinedFlags = {[flag]: true};
33 do {
34 const step = chainRegistry.get(prev);
35 if (step.call) {
36 step.call({...step.defaults, ...combinedFlags}, args);
37 prev = null;
38 } else {
39 combinedFlags[step.flag] = true;
40 prev = step.prev;
41 }
42 } while (prev);
43}
44
45function createHookChain(hook, isAfterHook) {
46 // Hook chaining rules:
47 // * `always` comes immediately after "after hooks"
48 // * `skip` must come at the end
49 // * no `only`
50 // * no repeating
51 extendChain(hook, 'cb', 'callback');
52 extendChain(hook, 'skip', 'skipped');
53 extendChain(hook.cb, 'skip', 'skipped');
54 if (isAfterHook) {
55 extendChain(hook, 'always');
56 extendChain(hook.always, 'cb', 'callback');
57 extendChain(hook.always, 'skip', 'skipped');
58 extendChain(hook.always.cb, 'skip', 'skipped');
59 }
60
61 return hook;
62}
63
64function createChain(fn, defaults, meta) {
65 // Test chaining rules:
66 // * `serial` must come at the start
67 // * `only` and `skip` must come at the end
68 // * `failing` must come at the end, but can be followed by `only` and `skip`
69 // * `only` and `skip` cannot be chained together
70 // * no repeating
71 const root = startChain('test', fn, {...defaults, type: 'test'});
72 extendChain(root, 'cb', 'callback');
73 extendChain(root, 'failing');
74 extendChain(root, 'only', 'exclusive');
75 extendChain(root, 'serial');
76 extendChain(root, 'skip', 'skipped');
77 extendChain(root.cb, 'failing');
78 extendChain(root.cb, 'only', 'exclusive');
79 extendChain(root.cb, 'skip', 'skipped');
80 extendChain(root.cb.failing, 'only', 'exclusive');
81 extendChain(root.cb.failing, 'skip', 'skipped');
82 extendChain(root.failing, 'only', 'exclusive');
83 extendChain(root.failing, 'skip', 'skipped');
84 extendChain(root.serial, 'cb', 'callback');
85 extendChain(root.serial, 'failing');
86 extendChain(root.serial, 'only', 'exclusive');
87 extendChain(root.serial, 'skip', 'skipped');
88 extendChain(root.serial.cb, 'failing');
89 extendChain(root.serial.cb, 'only', 'exclusive');
90 extendChain(root.serial.cb, 'skip', 'skipped');
91 extendChain(root.serial.cb.failing, 'only', 'exclusive');
92 extendChain(root.serial.cb.failing, 'skip', 'skipped');
93 extendChain(root.serial.failing, 'only', 'exclusive');
94 extendChain(root.serial.failing, 'skip', 'skipped');
95
96 root.after = createHookChain(startChain('test.after', fn, {...defaults, type: 'after'}), true);
97 root.afterEach = createHookChain(startChain('test.afterEach', fn, {...defaults, type: 'afterEach'}), true);
98 root.before = createHookChain(startChain('test.before', fn, {...defaults, type: 'before'}), false);
99 root.beforeEach = createHookChain(startChain('test.beforeEach', fn, {...defaults, type: 'beforeEach'}), false);
100
101 root.serial.after = createHookChain(startChain('test.after', fn, {...defaults, serial: true, type: 'after'}), true);
102 root.serial.afterEach = createHookChain(startChain('test.afterEach', fn, {...defaults, serial: true, type: 'afterEach'}), true);
103 root.serial.before = createHookChain(startChain('test.before', fn, {...defaults, serial: true, type: 'before'}), false);
104 root.serial.beforeEach = createHookChain(startChain('test.beforeEach', fn, {...defaults, serial: true, type: 'beforeEach'}), false);
105
106 // "todo" tests cannot be chained. Allow todo tests to be flagged as needing
107 // to be serial.
108 root.todo = startChain('test.todo', fn, {...defaults, type: 'test', todo: true});
109 root.serial.todo = startChain('test.serial.todo', fn, {...defaults, serial: true, type: 'test', todo: true});
110
111 root.meta = meta;
112
113 return root;
114}
115
116module.exports = createChain;