add a default terminal test runner

src/ansi.js

@@ -0,0 +1,55 @@
+import { mapObj, pipe } from './fn.js'
+
+export const Reset = Object.freeze({
+    All: 0,
+    Intensity: 22,
+    Italic: 23,
+    Underline: 24,
+    Blink: 25,
+    Reverse: 27,
+    Conceal: 28,
+    Strike: 29
+})
+
+export const Style = Object.freeze({
+    Bold: 1,
+    Faint: 2,
+    Italic: 3,
+    Underline: 4,
+    SlowBlink: 5,
+    RapidBlink: 6,
+    ReverseVideo: 7,
+    Conceal: 8,
+    Strike: 9
+})
+
+const ForegroundColor = Object.freeze({
+    Black: 30,
+    Red: 31,
+    Green: 32,
+    Yellow: 33,
+    Blue: 34,
+    Magenta: 35,
+    Cyan: 36,
+    White: 37,
+    Default: 39
+})
+
+const BackgroundColor = mapObj(
+    ([k, v]) => [k, v + 10]
+)(ForegroundColor)
+
+const sgr = args => `\x1b[${args.join(';')}m`
+
+export const Color = Object.freeze({
+    Foreground: ForegroundColor,
+    Background: BackgroundColor,
+
+    get fg() { return this.Foreground },
+    get bg() { return this.Background }
+})
+
+export const prepend = args => s => `${sgr(args)}${s}`
+export const append = args => s => `${s}${sgr(args)}`
+export const wrap = (start, end) => pipe(prepend(start), append(end))
+

src/fn.js

@@ -0,0 +1,22 @@
+
+export const exec = f => f()
+export const pipe = (...fns) => (x) => fns.reduce((v, f) => f(v), x)
+export const map = f => xs => xs.map(f)
+export const mapObj = f => pipe(Object.entries, map(f), Object.fromEntries)
+
+export const partition = (predicate, xs) => {
+    const passed = []
+    const failed = []
+
+    const len = xs.length
+    for (let i = 0; i < len; i++) {
+        const value = xs[i]
+        if (predicate(value)) {
+            passed.push(value)
+        } else {
+            failed.push(value)
+        }
+    }
+
+    return [passed, failed]
+}

src/runner.js

@@ -0,0 +1,95 @@
+import { Color, Style, Reset, wrap } from './ansi.js'
+import { exec, partition } from './fn.js'
+
+const { Yellow, Green, Red } = Color.Foreground
+const { Bold } = Style
+
+const reset = [Reset.All]
+const style = (s, ...args) => wrap(args, reset)(s)
+const fail = wrap([Red, Bold], reset)
+
+const process = ([name, tests]) => {
+    const results = tests.map(exec)
+
+    const [passed, failed] = partition(test => test.success, results)
+
+    return {
+        name,
+        passed,
+        failed,
+        results,
+        toString: () => {
+            const len = results.length
+            const passLen = passed.length
+            const failLen = failed.length
+
+            let color = Yellow
+
+            if (passLen === len) {
+                color = Green
+            } else if (failLen === len) {
+                color = Red
+            }
+            const header = `${style(name, Bold, color)} (${passLen}/${len})`
+
+            const text = results.map(result => {
+                const status = result.success ? 'pass' : fail('fail')
+                return `  ${result.description}... ${status}`
+            }).join('\n')
+
+            return `${header}\n${text}\n`
+        }
+    }
+}
+
+const makeSummary = results => {
+    const [passed, failed] = results.reduce(
+        ([pass, fail], result) => ([
+            pass + result.passed.length,
+            fail + result.failed.length,
+        ]),
+        [0, 0]
+    )
+    return {
+        passed,
+        failed,
+        toString() {
+            const failures = results
+                .filter(result => result.failed.length)
+                .flatMap(result => {
+                    return result.failed.map(({ description, error }) => {
+                        return `  ${result.name}::${description}\n${error.stack}`
+                    }).join('\n\n')
+                }).join('\n\n')
+
+            const summary = `test result: ${failed}. ${passed} passed; ${failed} failed`
+
+            return `failures:\n${failures}\n\n${summary}`
+        }
+    }
+}
+export const term = tests => {
+    const suites = Object.entries(tests).map(process)
+    suites.forEach(s => console.log(s.toString()))
+    console.log(makeSummary(suites).toString())
+
+}
+
+const mock = (success, description, error) => () => ({ success, description, error })
+
+term({
+    SuccessTest: [
+        mock(true, 'Unit 1'),
+        mock(true, 'Unit 2')
+    ],
+    MixedTest: [
+        mock(false, 'Unit 3', new Error('bb')),
+        mock(true, 'Unit 4'),
+        mock(true, 'Unit 5')
+    ],
+    FailTest: [
+        mock(false, 'Unit 6', new Error('aa')),
+        mock(false, 'Unit 7', new Error('cc')),
+    ]
+})
+