feat: pass argument to main function

.npmignore

@@ -1,2 +1,2 @@
 node_modules/
-assets/screenshot.png
+assets/screenshot.png

__tests__/index.test.js → __tests__/integration/index.test.js

@@ -3,10 +3,10 @@
 const path = require("path");
 const fs = require("mz/fs");
 const linter = require("addons-linter");
-const withTmpDir = require("./helpers/tmp-dir");
-const cmdRunner = require("./helpers/cmd-runner");
+const withTmpDir = require("../helpers/tmp-dir");
+const cmdRunner = require("../helpers/cmd-runner");
 
-const execDirPath = path.join(__dirname, "..", "bin");
+const execDirPath = path.join(__dirname, "../..", "bin");
 
 describe("main", () => {
   test("creates files including manifest with correct name", () => withTmpDir(

__tests__/unit/errors.test.js

@@ -0,0 +1,23 @@
+"use strict";
+
+const UsageError = require("../../errors").UsageError;
+const onlyInstancesOf = require("../../errors").onlyInstancesOf;
+
+describe("onlyInstancesOf", () => {
+  test("catches specified error", () => {
+    return Promise.reject(new UsageError("fake usage error"))
+      .catch(onlyInstancesOf(UsageError, (error) => {
+        expect(error).toBeInstanceOf(UsageError);
+      }));
+  });
+
+  test("throws other errors", () => {
+    return Promise.reject(new Error("fake error"))
+      .catch(onlyInstancesOf(UsageError, () => {
+        throw new Error("Unexpectedly caught the wrong error");
+      }))
+      .catch((error) => {
+        expect(error.message).toMatch(/fake error/);
+      });
+  });
+});

__tests__/unit/index.test.js

@@ -0,0 +1,127 @@
+"use strict";
+
+const path = require("path");
+const chalk = require("chalk");
+const fs = require("mz/fs");
+const withTmpDir = require("../helpers/tmp-dir");
+const onlyInstancesOf = require("../../errors").onlyInstancesOf;
+const UsageError = require("../../errors").UsageError;
+const main = require("../../index").main;
+const MORE_INFO_MSG = require("../../index").MORE_INFO_MSG;
+const asciiLogo = require("../../index").asciiLogo;
+
+describe("main", () => {
+  test("returns project path and creation message", () => withTmpDir(
+    async (tmpPath) => {
+      const projName = "target";
+      const targetDir = path.join(tmpPath, projName);
+      const expectedMessage =
+      `${asciiLogo} \n
+  Congratulations!!! A new WebExtension has been created at:
+
+  ${chalk.bold(chalk.green(targetDir))} ${MORE_INFO_MSG}`;
+
+      const result = await main({
+        dirPath: projName,
+        baseDir: tmpPath,
+      });
+      expect(result.projectPath).toEqual(targetDir);
+      expect(result.projectCreatedMessage).toEqual(expectedMessage);
+    })
+  );
+
+  test("creates files, readme and manifest with correct name", () => withTmpDir(
+    async (tmpPath) => {
+      const projName = "target";
+      const targetDir = path.join(tmpPath, projName);
+
+      await main({
+        dirPath: projName,
+        baseDir: tmpPath,
+      });
+
+      const contentStat = await fs.stat(path.join(targetDir, "content.js"));
+      expect(contentStat.isDirectory()).toBeFalsy();
+
+      const bgStat = await fs.stat(path.join(targetDir, "background.js"));
+      expect(bgStat.isDirectory()).toBeFalsy();
+
+      const rmStat = await fs.stat(path.join(targetDir, "README.md"));
+      expect(rmStat.isDirectory()).toBeFalsy();
+
+      const manifest = await fs.readFile(path.join(targetDir, "manifest.json"), "utf-8");
+      const parsed = JSON.parse(manifest);
+      expect(parsed.name).toEqual(projName);
+    })
+  );
+
+  test("calls all of its necessary dependencies", () => withTmpDir(
+    async (tmpPath) => {
+      const projName = "target";
+      const targetDir = path.join(tmpPath, projName);
+
+      const getProjectManifestMock = jest.fn();
+      const getPlaceholderIconMock = jest.fn();
+      const getProjectReadmeMock = jest.fn();
+      const getProjectCreatedMessageMock = jest.fn();
+
+      await main({
+        dirPath: projName,
+        baseDir: tmpPath,
+        getProjectManifestFn: getProjectManifestMock,
+        getPlaceholderIconFn: getPlaceholderIconMock,
+        getProjectReadmeFn: getProjectReadmeMock,
+        getProjectCreatedMessageFn: getProjectCreatedMessageMock,
+      });
+
+      expect(getProjectManifestMock.mock.calls.length).toBe(1);
+      expect(getProjectManifestMock.mock.calls[0][0]).toBe(projName);
+
+      expect(getPlaceholderIconMock.mock.calls.length).toBe(1);
+
+      expect(getProjectReadmeMock.mock.calls.length).toBe(1);
+      expect(getProjectReadmeMock.mock.calls[0][0]).toBe(projName);
+
+      expect(getProjectCreatedMessageMock.mock.calls.length).toBe(1);
+      expect(getProjectCreatedMessageMock.mock.calls[0][0]).toBe(targetDir);
+    })
+  );
+
+  test("throws Usage Error when directory already exists", () => withTmpDir(
+    async (tmpPath) => {
+      const projName = "target";
+      const targetDir = path.join(tmpPath, projName);
+      await fs.mkdir(targetDir);
+
+      try {
+        await main({
+          dirPath: projName,
+          baseDir: tmpPath,
+        });
+      } catch (error) {
+        onlyInstancesOf(UsageError, () => {
+          expect(error.message).toMatch(/dir already exists/);
+        });
+      }
+    })
+  );
+
+  test("throws error when directory already exists", () => withTmpDir(
+    async (tmpPath) => {
+      const projName = "target";
+      const getPlaceholderIconMock = jest.fn(() => {
+        throw new Error("error");
+      });
+
+      try {
+        await main({
+          dirPath: projName,
+          baseDir: tmpPath,
+          getPlaceholderIconFn: getPlaceholderIconMock,
+        });
+      } catch (error) {
+        expect(error.message).toMatch(/error/);
+      }
+    })
+  );
+});

bin/create-webextension

@@ -1,3 +1,24 @@
 #!/usr/bin/env node
+const chalk = require("chalk");
+const UsageError = require("../errors").UsageError;
+const onlyInstancesOf = require("../errors").onlyInstancesOf;
 
-require("..").main();
+
+const USAGE_MSG = `Usage: create-webextension project_dir_name`;
+
+if (!process.argv[2]) {
+  console.error(`${chalk.red("Missing project dir name.")}\n`);
+  console.log(USAGE_MSG);
+  process.exit(1);
+}
+
+require("..").main({dirPath: process.argv[2]})
+  .then(({projectCreatedMessage}) => console.log(projectCreatedMessage))
+  .catch(onlyInstancesOf(UsageError, (error) => {
+    console.error(`${chalk.red(error.message)}\n`);
+    process.exit(1);
+  }))
+  .catch((error) => {
+    console.error(`${chalk.red(error.message)}: ${error.stack}\n`); // or something similar that prints both the message and the stack
+    process.exit(1);
+  });

errors.js

@@ -0,0 +1,12 @@
+const ES6Error = require("es6-error");
+
+exports.onlyInstancesOf = function (errorType, handler) {
+  return (error) => {
+    if (error instanceof errorType) {
+      return handler(error);
+    }
+    throw error;
+  };
+};
+
+exports.UsageError = class UsageError extends ES6Error {};

index.js

@@ -4,8 +4,7 @@ const path = require("path");
 const chalk = require("chalk");
 const fs = require("mz/fs");
 const stripAnsi = require("strip-ansi");
-
-const USAGE_MSG = `Usage: create-webextension project_dir_name`;
+const UsageError = require("./errors").UsageError;
 
 const README = `
 This project contains a blank WebExtension addon, a "white canvas" for your new experiment of
@@ -36,16 +35,17 @@ a WebExtension from the command line:
   ${chalk.bold.blue("web-ext run -s /path/to/extension")}
 `;
 
+const asciiLogo = fs.readFileSync(
+  path.join(__dirname, "assets", "webextension-logo.ascii")
+);
+
 function getProjectCreatedMessage(projectPath) {
-  return fs.readFile(path.join(__dirname, "assets", "webextension-logo.ascii"))
-           .then(asciiLogo => {
-             const PROJECT_CREATED_MSG = `\n
-Congratulations!!! A new WebExtension has been created at:
+  const PROJECT_CREATED_MSG = `\n
+  Congratulations!!! A new WebExtension has been created at:
 
   ${chalk.bold(chalk.green(projectPath))}`;
 
-             return `${asciiLogo} ${PROJECT_CREATED_MSG} ${MORE_INFO_MSG}`;
-           });
+  return `${asciiLogo} ${PROJECT_CREATED_MSG} ${MORE_INFO_MSG}`;
 }
 
 function getProjectReadme(projectDirName) {
@@ -87,39 +87,48 @@ function getProjectManifest(projectDirName) {
   };
 }
 
-exports.main = function main() {
-  if (!process.argv[2]) {
-    console.error(`${chalk.red("Missing project dir name.")}\n`);
-    console.log(USAGE_MSG);
-    process.exit(1);
+function main({
+  dirPath,
+  baseDir = process.cwd(),
+  getProjectManifestFn = getProjectManifest,
+  getPlaceholderIconFn = getPlaceholderIcon,
+  getProjectReadmeFn = getProjectReadme,
+  getProjectCreatedMessageFn = getProjectCreatedMessage,
+}) {
+  if (!dirPath) {
+    throw new Error("Project directory name is a mandatory argument");
   }
 
-  const projectPath = path.resolve(process.argv[2]);
+  const projectPath = path.resolve(baseDir, dirPath);
   const projectDirName = path.basename(projectPath);
 
   return fs.mkdir(projectPath).then(() => {
     return Promise.all([
       fs.writeFile(path.join(projectPath, "manifest.json"),
-                   JSON.stringify(getProjectManifest(projectDirName), null, 2)),
+                   JSON.stringify(getProjectManifestFn(projectDirName), null, 2)),
       fs.writeFile(path.join(projectPath, "background.js"),
                    `console.log("${projectDirName} - background page loaded");`),
       fs.writeFile(path.join(projectPath, "content.js"),
                    `console.log("${projectDirName} - content script loaded");`),
-    ]).then(() => getPlaceholderIcon())
+    ]).then(() => getPlaceholderIconFn())
       .then(iconData => fs.writeFile(path.join(projectPath, "icon.png"), iconData))
-      .then(() => getProjectReadme(projectDirName))
+      .then(() => getProjectReadmeFn(projectDirName))
       .then(projectReadme => fs.writeFile(path.join(projectPath, "README.md"),
                                           stripAnsi(projectReadme)))
-      .then(() => getProjectCreatedMessage(projectPath))
-      .then(console.log);
+      .then(async () => {
+        const projectCreatedMessage = await getProjectCreatedMessageFn(projectPath);
+        return {projectPath, projectCreatedMessage};
+      });
   }, error => {
     if (error.code === "EEXIST") {
-      const msg = `Unable to create a new WebExtension: ${chalk.bold.underline(projectPath)} dir already exist.`;
-      console.error(`${chalk.red(msg)}\n`);
-      process.exit(1);
+      const msg = `Unable to create a new WebExtension: ${chalk.bold.underline(projectPath)} dir already exists.`;
+      throw new UsageError(msg);
     }
-  }).catch((error) => {
-    console.error(error);
-    process.exit(1);
   });
+}
+
+module.exports = {
+  main,
+  MORE_INFO_MSG,
+  asciiLogo,
 };

package.json

@@ -33,6 +33,7 @@
   "homepage": "https://github.com/rpl/create-webextension#readme",
   "dependencies": {
     "chalk": "^1.1.3",
+    "es6-error": "^4.0.2",
     "mz": "^2.6.0",
     "strip-ansi": "^3.0.1"
   },