INIT - setup test runner

Author: ShMcK

coderoad/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "coderoad-fcc-learn-npm",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/coderoad/fcc-learn-npm"
+  },
+  "scripts": {
+    "test": "mocha",
+    "programmatic-test": "mocha --reporter=mocha-tap-reporter"
+  },
+  "dependencies": {
+    "mocha": "^7.0.1",
+    "mocha-tap-reporter": "^0.1.3"
+  }
+}

coderoad/test/utils.js

@@ -0,0 +1,116 @@
+const fs = require("fs");
+const path = require("path");
+const util = require("util");
+const { join } = require("path");
+
+const readFile = util.promisify(fs.readFile);
+const readdir = util.promisify(fs.readdir);
+
+const getPackageJson = async (dir = path.join(process.cwd(), "..")) => {
+  // load package.json file
+  const pathToPackageJson = join(dir, "package.json");
+  const packageJson = await readFile(pathToPackageJson, "utf8").catch(
+    console.error
+  );
+  if (!packageJson) {
+    throw new Error("Missing root package.json");
+  }
+  // parse as JSON
+  const json = JSON.parse(packageJson);
+  if (!json) {
+    throw new Error("The package.json content looks invalid");
+  }
+  return json;
+};
+
+exports.getPackageJson = getPackageJson;
+
+const versionMatch = (current, expected) => {
+  let currentSemver = current;
+  if (["~", "^"].includes(current[0])) {
+    currentSemver = current.substring(1);
+  }
+  return currentSemver === expected;
+};
+
+/**
+ * isModuleInstalled
+ * @param { name, type } params
+ * "name" - the name of the dependency
+ * "type" - "dependency", "devDependency", "peerDependency"
+ * @returns boolean
+ */
+const isModuleInstalled = async ({ name, type, version }) => {
+  // 1. load package.json file
+  const json = await getPackageJson();
+
+  // 2. verify package lists dependency by type
+  let installCommand;
+  let hasDependency;
+  let currentVersion;
+
+  switch (type) {
+    case "dependency":
+      installCommand = "--save";
+      hasDependency = !!json.dependencies && json.dependencies[name];
+      currentVersion = json.dependencies[name];
+      break;
+    case "devDependency":
+      installCommand = "--save-dev";
+      hasDependency = !!json.devDependencies && json.devDependencies[name];
+      currentVersion = json.devDependencies[name];
+      break;
+    case "peerDependency":
+      throw new Error("Peer dependencies unsupported");
+    default:
+      throw new Error("Unsupported packaged type");
+  }
+
+  if (!hasDependency) {
+    throw new Error(`Run "npm install ${installCommand} ${name}"`);
+  }
+
+  // 3. if version, check dependency version
+  if (version && !versionMatch(currentVersion, version)) {
+    throw new Error(
+      `Dependency ${name} version ${currentVersion} does not match expected ${version}`
+    );
+  }
+
+  // 4. verify node_module installed
+  const pathToNodeModule = join(process.cwd(), "..", "node_modules", name);
+  const hasNodeModules = await readdir(pathToNodeModule).catch(() => {
+    throw new Error('Missing node_modules. Run "npm install"');
+  });
+  if (!hasNodeModules) {
+    throw new Error('Missing node_modules. Run "npm install"');
+  }
+
+  // 5. if version, has installed node_module version
+  if (version) {
+    const nodeModulePackageJson = await getPackageJson(pathToNodeModule);
+    if (!versionMatch(nodeModulePackageJson.version, version)) {
+      throw new Error(
+        `Dependency ${name} version ${version} is not yet installed. Run "npm install"`
+      );
+    }
+  }
+
+  return true;
+};
+
+exports.isModuleInstalled = isModuleInstalled;
+
+// created because assert.doesNotThrow not working predictably with async fns
+const doesNotThrow = async (fn) => {
+  let result = true;
+  try {
+    await fn();
+  } catch (error) {
+    console.error(error);
+    result = false;
+  }
+  return result;
+};
+
+exports.doesNotThrow = doesNotThrow;