feat(logging): improve logging, especially for errors (#56)

.github/ISSUE_TEMPLATE.md

@@ -0,0 +1,46 @@
+<!--
+Thanks for your interest in the project. I appreciate bugs filed and PRs submitted!
+Please make sure that you are familiar with and follow the Code of Conduct for
+this project (found in the CODE_OF_CONDUCT.md file).
+
+Please fill out this template with all the relevant information so we can
+understand what's going on and fix the issue.
+
+I'll probably ask you to submit the fix (after giving some direction). If you've
+never done that before, that's great! Check this free short video tutorial to
+learn how: http://kcd.im/pull-request
+-->
+
+- `prettier-eslint-cli` version:
+- `prettier` version:
+- `eslint` version:
+
+Relevant code/config.
+
+```javascript
+
+```
+
+What you did:
+
+
+
+What happened:
+
+<!-- Please provide the full error message/screenshots/anything -->
+
+Reproduction:
+
+<!--
+Please reproduce your issue by forking this repository:
+  https://github.com/kentcdodds/prettier-eslint-cli-repro
+with as minimal amount of code possible. Then paste a link below:
+-->
+
+-- paste your link here --
+
+Problem description:
+
+
+
+Suggested solution:

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,27 @@
+<!--
+Thanks for your interest in the project. I appreciate bugs filed and PRs submitted!
+
+Please make sure that you are familiar with and follow the Code of Conduct for
+this project (found in the CODE_OF_CONDUCT.md file).
+
+Also, please make sure you're familiar with and follow the instructions in the
+contributing guidelines (found in the CONTRIBUTING.md file).
+
+If you're new to contributing to open source projects, you might find this free
+video course helpful: http://kcd.im/pull-request
+
+Please fill out the information below to expedite the review and (hopefully)
+merge of your pull request!
+-->
+
+<!-- What changes are being made? (What feature/bug is being fixed here?) -->
+**What**:
+
+<!-- Why are these changes necessary? -->
+**Why**:
+
+<!-- How were these changes implemented? -->
+**How**:
+
+
+<!-- feel free to add additional comments -->

src/__snapshots__/uncaught-exception-handler.test.js.snap

@@ -0,0 +1,17 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`logs a check for trace 1`] = `
+"There has been an unknown error when running the prettier-eslint CLI. If it's unclear to you what went wrong, then try this: 
+  ✅  Run the script again with the LOG_LEVEL environment variable set to \\"trace\\"
+  2. Search existing issues on GitHub: https://github.com/prettier/prettier-eslint-cli/issues?utf8=%E2%9C%93&q=my%20error
+  3. Make a minimal reproduction in a totally separate repository. You can fork this one: https://github.com/kentcdodds/prettier-eslint-cli-repro
+  4. Post an issue with a link to your reproduction to the issues on GitHub: https://github.com/prettier/prettier-eslint-cli/issues/new"
+`;
+
+exports[`logs all options 1`] = `
+"There has been an unknown error when running the prettier-eslint CLI. If it's unclear to you what went wrong, then try this: 
+  1. Run the script again with the LOG_LEVEL environment variable set to \\"trace\\"
+  2. Search existing issues on GitHub: https://github.com/prettier/prettier-eslint-cli/issues?utf8=%E2%9C%93&q=my%20error
+  3. Make a minimal reproduction in a totally separate repository. You can fork this one: https://github.com/kentcdodds/prettier-eslint-cli-repro
+  4. Post an issue with a link to your reproduction to the issues on GitHub: https://github.com/prettier/prettier-eslint-cli/issues/new"
+`;

src/add-exception-handler.js

@@ -0,0 +1,4 @@
+/* istanbul ignore-next */
+import onUncaughtException from './uncaught-exception-handler'
+
+process.on('uncaughtException', onUncaughtException)

src/index.js

@@ -1,8 +1,15 @@
 #!/usr/bin/env node
 
+// eslint-disable-next-line import/no-unassigned-import
+import './add-exception-handler' // want to do this first
+import getLogger from 'loglevel-colored-level-prefix'
 import parser from './parser'
 import formatFiles from './format-files'
 
-const argv = parser.parse(process.argv.slice(2))
+const logger = getLogger({prefix: 'prettier-eslint-cli'})
+const args = process.argv.slice(2)
+
+logger.trace('Parsing args: ', args)
+const argv = parser.parse(args)
 
 formatFiles(argv)

src/parser.js

@@ -1,4 +1,5 @@
 import path from 'path'
+import getLogger from 'loglevel-colored-level-prefix'
 import findUp from 'find-up'
 import yargs from 'yargs'
 import {oneLine} from 'common-tags'
@@ -7,6 +8,8 @@ import camelcaseKeys from 'camelcase-keys'
 import chalk from 'chalk'
 import boolify from 'boolify'
 
+const logger = getLogger({prefix: 'prettier-eslint-cli'})
+
 const parser = yargs
   .usage('Usage: $0 <globs>... [--option-1 option-1-value --option-2]')
   .help('h')
@@ -40,10 +43,10 @@ const parser = yargs
     },
     ignore: {
       describe: oneLine`
-          pattern(s) you wish to ignore
-          (can be used multiple times
-          and includes **/node_modules/** automatically)
-        `,
+        pattern(s) you wish to ignore
+        (can be used multiple times
+        and includes **/node_modules/** automatically)
+      `,
       coerce: arrify,
     },
     'log-level': {
@@ -59,9 +62,10 @@ const parser = yargs
     },
     prettier: {
       describe: oneLine`
-          Prettier configuration options 
-          to be passed to prettier-eslint
-          using dot-notation`,
+        Prettier configuration options
+        to be passed to prettier-eslint
+        using dot-notation
+      `,
     },
     // TODO: if we allow people to to specify a config path,
     // we need to read that somehow. These can come invarious
@@ -78,8 +82,10 @@ const parser = yargs
     } else {
       throw Error(
         chalk.red(
-          oneLine`You should use dot-notation with 
-          the --prettier flag, for example, --prettier.singleQuote`,
+          oneLine`
+            You should use dot-notation with
+            the --prettier flag, for example, --prettier.singleQuote
+          `,
         ),
       )
     }
@@ -89,11 +95,18 @@ const parser = yargs
 export default parser
 
 function getPathInHostNodeModules(module) {
+  logger.debug(`Looking for a local installation of the module "${module}"`)
   const modulePath = findUp.sync(`node_modules/${module}`)
 
   if (modulePath) {
     return modulePath
   }
+  logger.debug(
+    oneLine`
+      Local installation of "${module}" not found,
+      looking again starting in "${__dirname}"
+    `,
+  )
 
   return findUp.sync(`node_modules/${module}`, {cwd: __dirname})
 }

src/uncaught-exception-handler.js

@@ -0,0 +1,42 @@
+import {oneLine, oneLineTrim} from 'common-tags'
+import getLogger from 'loglevel-colored-level-prefix'
+
+const logger = getLogger({prefix: 'prettier-eslint-cli'})
+
+export default onUncaughtException
+
+function onUncaughtException(err) {
+  const level = logger.getLevel()
+  const isTrace = level === 0
+  const traceResolution = oneLine`
+    Run the script again with the LOG_LEVEL
+    environment variable set to "trace"
+  `
+  const resolutionSteps = [
+    `${isTrace ? '✅ ' : '1.'} ${traceResolution}`,
+    oneLine`
+      2. Search existing issues on GitHub:
+      ${oneLineTrim`
+        https://github.com/prettier/prettier-eslint-cli/issues
+        ?utf8=%E2%9C%93&q=${encodeURIComponent(err.message)}
+      `}
+    `,
+    oneLine`
+      3. Make a minimal reproduction in a totally separate repository.
+      You can fork this one:
+      https://github.com/kentcdodds/prettier-eslint-cli-repro
+    `,
+    oneLine`
+      4. Post an issue with a link to your reproduction to the issues
+      on GitHub: https://github.com/prettier/prettier-eslint-cli/issues/new
+    `,
+  ].join('\n  ')
+  logger.error(
+    oneLine`
+      There has been an unknown error when running the prettier-eslint CLI.
+      If it's unclear to you what went wrong, then try this:
+    `,
+    `\n  ${resolutionSteps}`,
+  )
+  throw err
+}

src/uncaught-exception-handler.test.js

@@ -0,0 +1,58 @@
+import getLoggerMock from 'loglevel-colored-level-prefix'
+import onUncaughtException from './uncaught-exception-handler'
+
+jest.mock('loglevel-colored-level-prefix', () => {
+  const logger = {}
+  const __mock__ = {logger, level: 4, resetAll}
+  const getLogger = jest.fn(() => resetAll())
+  getLogger.__mock__ = __mock__
+  return getLogger
+
+  function resetAll() {
+    getLogger.mockClear()
+    Object.assign(logger, {
+      getLevel: jest.fn(() => getLogger.__mock__.level),
+      trace: jest.fn(),
+      debug: jest.fn(),
+      info: jest.fn(),
+      warn: jest.fn(),
+      error: jest.fn(),
+    })
+    return logger
+  }
+})
+
+beforeEach(() => {
+  getLoggerMock.__mock__.resetAll()
+})
+
+test('logs all options', () => {
+  const logger = getLoggerMock()
+  runWithCatch(new Error('my error'))
+  expect(logger.error).toHaveBeenCalledTimes(1)
+  const errorLog = logger.error.mock.calls[0].join(' ')
+  expect(errorLog).toMatchSnapshot()
+})
+
+test('logs a check for trace', () => {
+  getLoggerMock.__mock__.level = 0
+  const logger = getLoggerMock()
+  runWithCatch(new Error('my error'))
+  expect(logger.error).toHaveBeenCalledTimes(1)
+  const errorLog = logger.error.mock.calls[0].join(' ')
+  expect(errorLog).toContain('✅')
+  expect(errorLog).toMatchSnapshot()
+})
+
+test('re-throws the given error', () => {
+  const myError = new Error('my error')
+  expect(() => onUncaughtException(myError)).toThrow(myError)
+})
+
+function runWithCatch(...args) {
+  try {
+    onUncaughtException(...args)
+  } catch (e) {
+    // ignore
+  }
+}