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 +1,66 @@
+"use strict";
+//@ts-check
+
+const test = require("tap").test;
+const execFile = require("child_process").execFile;
+const path = require("path");
+const { stderr } = require("process");
+
+require("npmlog").level = "warn";
+
+//! tests: {path: string, name: string}[]
+//*can use name as short descriptions
+const tests = [{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 tests
+
+  //!this must contain t: Test and exec: {path: string, name: string} fields
+
+  @private
+  @argument {Error} err - exec error
+  @argument {Buffer} stdout - stdout buffer of child process
+  @argument {stderr} stderr
+ */
+function check(err, stdout, stderr) {
+  let { t, exec } = this;
+  if (!err && !stderr) {
+    t.strictEqual(stdout.trim(), exec.path, `${exec.name}: check path ${exec.path} equals ${stdout.trim()}`);
+  } else {
+    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(tests.length);
+
+  // context for check functions
+  let ctx = {
+    t: t,
+    exec: {},
+  };
+
+  for (let exec of tests) {
+    //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
+      let boundedCheck = check.bind(Object.assign({}, ctx))
+      execFile(exec.path, args, options, boundedCheck);
+    } else {
+      t.skip(`skipped: ${exec.name} doesn't exist or unavailable`)
+    }
+  }
+});