test: add unit test for find-python-script.py

created file test-find-python-script.py

Author: owl-from-hogvarts

test/test-find-python-script.js

@@ -0,0 +1,83 @@
+// @ts-check
+'use strict'
+/** @typedef {import("tap")} Tap */
+
+const test = require('tap').test
+const execFile = require('child_process').execFile
+const path = require('path')
+
+require('npmlog').level = 'warn'
+
+//* can use name as short descriptions
+
+/**
+ * @typedef Check
+ * @property {string} path - path to execurtable or command
+ * @property {string} name - very little description
+ */
+
+/**
+ * @type {Check[]}
+ */
+const checks = [
+  { path: process.env.PYTHON, name: 'env var PYTHON' },
+  { path: process.env.python2, name: 'env var python2' },
+  { path: 'python3', name: 'env var python3' }
+]
+const args = [path.resolve('./lib/find-python-script.py')]
+const options = {
+  windowsHide: true
+}
+
+/**
+  Getting output from find-python-script.py,
+  compare it to path provided to terminal.
+  If equale - test pass
+
+  runs for all checks
+
+  @private
+  @argument {Error} err - exec error
+  @argument {string} stdout - stdout buffer of child process
+  @argument {string} stderr
+  @this {{t, exec: Check}}
+ */
+function check (err, stdout, stderr) {
+  const { t, exec } = this
+  if (!err && !stderr) {
+    t.strictEqual(
+      stdout.trim(),
+      exec.path,
+      `${exec.name}: check path ${exec.path} equals ${stdout.trim()}`
+    )
+  } else {
+    // @ts-ignore
+    if (err.code === 9009) {
+      t.skip(`skipped: ${exec.name} file not found`)
+    } else {
+      t.fail(`error: ${err}\n\nstderr: ${stderr}`)
+    }
+  }
+}
+
+test('find-python-script', (t) => {
+  t.plan(checks.length)
+
+  // context for check functions
+  const ctx = {
+    t: t,
+    exec: {}
+  }
+
+  for (const exec of checks) {
+    // checking if env var exist
+    if (!(exec.path === undefined || exec.path === null)) {
+      ctx.exec = exec
+      // passing ctx as coppied object to make properties immutable from here
+      const boundedCheck = check.bind(Object.assign({}, ctx))
+      execFile(exec.path, args, options, boundedCheck)
+    } else {
+      t.skip(`skipped: ${exec.name} doesn't exist or unavailable`)
+    }
+  }
+})