Print Derived Configuration Report

feat: print derived config variables
feat: print derived config variables in json
test: 12 new unit tests to support features
test: 1 skipped unit test for discovered bug in yargs with reports param

c8-ascii-art.txt

@@ -0,0 +1,9 @@
+/* ________/\\\\\\\\\_        _____/\\\\\\\\\____         */
+/*  _____/\\\////////__        ___/\\\///////\\\__        */
+/*   ___/\\\/___________        __\/\\\_____\/\\\__       */
+/*    __/\\\_____________        __\///\\\\\\\\\/___      */
+/*     _\/\\\_____________        ___/\\\///////\\\__     */
+/*      _\//\\\____________        __/\\\______\//\\\_    */
+/*       __\///\\\__________        _\//\\\______/\\\__   */
+/*        ____\////\\\\\\\\\_        __\///\\\\\\\\\/___  */
+/*         _______\/////////__        ____\/////////_____ */

lib/parse-args.js

@@ -158,8 +158,17 @@ function buildYargs (withCommands = false) {
       describe: 'supplying --merge-async will merge all v8 coverage reports asynchronously and incrementally. ' +
         'This is to avoid OOM issues with Node.js runtime.'
     })
+    .options('print-config', {
+      default: false,
+      type: 'boolean',
+      describe: 'Print the derived configuration between command line parameters and loaded configuration file'
+    })
+    .options('print-config-format', {
+      default: 'text',
+      type: 'string',
+      describe: 'Format to print the configuration in.  Accepted formats are either text or json'
+    })
     .pkgConf('c8')
-    .demandCommand(1)
     .check((argv) => {
       if (!argv.tempDirectory) {
         argv.tempDirectory = resolve(argv.reportsDir, 'tmp')
@@ -181,6 +190,38 @@ function buildYargs (withCommands = false) {
   //   }
   // })
 
+  const argv = process.argv.slice(2)
+  const checkArgs = parser(argv)
+
+  let shouldPrint = false
+
+  if (Object.keys(checkArgs).includes('print-config')) {
+    // checkArgs['print-config'] could contain a boolean or a string
+    // representing a boolean.
+    if (typeof checkArgs['print-config'] === 'boolean') {
+      shouldPrint = checkArgs['print-config']
+    } else if (typeof checkArgs['print-config'] === 'string') {
+      shouldPrint = JSON.parse(checkArgs['print-config'])
+    }
+  }
+
+  if (shouldPrint) {
+    const commandExecutedReference = 'c8 ' + argv.join(' ')
+    const args = yargs.parse(hideInstrumenteeArgs())
+    const cleanArgs = cleanUpArgumentArray(args)
+
+    if (args.printConfigFormat === 'text') {
+      printConfigText(cleanArgs, commandExecutedReference)
+    } else if (checkArgs.printConfigFormat === 'json') {
+      const jsonYargs = JSON.stringify(cleanArgs, 2)
+      console.log(jsonYargs)
+    }
+
+    process.exit()
+  }
+
+  yargs.demandCommand(1)
+
   const checkCoverage = require('./commands/check-coverage')
   const report = require('./commands/report')
   if (withCommands) {
@@ -217,6 +258,103 @@ function hideInstrumenteeArgs () {
   return argv
 }
 
+// Todo: Take a look at Optimizing this function
+// exclude certain temporary values and duplicates from printing
+// the same variable will be included twice with different keys
+// for example args['temp-directory'] && args['tempDirectory']
+// are essentially the same variable
+function cleanUpArgumentArray (args) {
+  const argsToPrint = {}
+  Object.keys(args).forEach(v => {
+    if (v && v.length > 1 && v !== '_' && v !== '$0') {
+      // See if we are dealing with a Camel Case key string
+      const matches = [...v.matchAll(/([A-Z])/g)]
+      if (matches.length > 0) {
+        matches.forEach(m => {
+          // Derive Kebab Case string from Camel Case Key string
+          const newKey = m.input.replace(/([A-Z])/g, '-$1').toLowerCase()
+          // If the Kebab Case key is not assigned a value
+          if (!args[newKey]) {
+            // Then assigned it the Camel Case Variable
+            argsToPrint[newKey] = args[v]
+          } else if (!args[v]) {
+            // Other wise assign keep the Kebab Case key value
+            argsToPrint[newKey] = args[newKey]
+          }
+        })
+      } else {
+        // Just keep the value.  Either Kebab case or otherwise
+        argsToPrint[v] = args[v]
+      }
+    }
+  })
+
+  return argsToPrint
+}
+
+function printConfigText (argsv, commandExecutedReference) {
+  const banner = readFileSync('./c8-ascii-art.txt', 'utf-8')
+  console.log('\n\n')
+  console.log(banner)
+  console.log('\n\n')
+  console.log('Command Issued:     ' + commandExecutedReference)
+  console.log('Config File Loaded: ' + argsv.config + '\n\n\n')
+  console.log('Derived Configuration from CLI options and configuration file')
+  console.log('------------------------------------------------------------------------------')
+
+  const addSpace = (numOfSpace) => {
+    let space = ''
+    for (let i = 0; i < numOfSpace; i++) space += ' '
+    const s = space
+    return s
+  }
+
+  // Including some formatting variables
+  // for spacing to make the output more readable
+  let output = ''
+  let spaceLength = Object.keys(argsv)
+    .map(v => String(v).length)
+    .reduce((p, c) => {
+      return (p >= c) ? p : c
+    })
+  spaceLength += 10
+
+  // For each configuration value, print pretty
+  Object.keys(argsv).forEach(v => {
+    const fillSpace = addSpace(spaceLength - v.length)
+    const enumSpace = addSpace(spaceLength)
+    const value = formatPrintVariable(argsv[v], enumSpace)
+    output += String(v) + ':' + fillSpace + value + '\n'
+  })
+  console.log(output)
+}
+
+function formatPrintVariable (variable, space) {
+  let value
+
+  if (Array.isArray(variable) && variable.length > 0) {
+    value = stringifyObject(variable, space, ']')
+  } else if (typeof variable === 'object' && Object.keys(variable).length > 0) {
+    value = stringifyObject(variable, space, '}')
+  } else if (typeof variable === 'string' && variable) {
+    value = "'" + variable + "'"
+  } else if (typeof variable === 'string' && !variable) {
+    value = "''"
+  } else {
+    value = variable
+  }
+
+  return value
+}
+
+function stringifyObject (variable, space, closingChar) {
+  const closeReg = new RegExp('\n' + closingChar, 'g')
+  const out = JSON.stringify(variable, null, '\t\t\t\t ')
+    .replace(closeReg, '\n' + space + ' ' + closingChar)
+
+  return out
+}
+
 module.exports = {
   buildYargs,
   hideInstrumenterArgs,