feat: add badge for .nycrc config based coverage, run [nycrc] (#4759)

* feat: add badge for .nycrc coverage

* chore: address code review

* chore: address additional review

* chore: address a tiny bit more of review

* chore: address edge case

* chore: address LGTM review

services/nycrc/nycrc.service.js

@@ -0,0 +1,160 @@
+'use strict'
+
+const Joi = require('@hapi/joi')
+const { coveragePercentage } = require('../color-formatters')
+const {
+  ConditionalGithubAuthV3Service,
+} = require('../github/github-auth-service')
+const { fetchJsonFromRepo } = require('../github/github-common-fetch')
+const { InvalidParameter, InvalidResponse, NotFound } = require('..')
+
+const nycrcSchema = Joi.object({
+  branches: Joi.number()
+    .min(0)
+    .max(100),
+  lines: Joi.number()
+    .min(0)
+    .max(100),
+  functions: Joi.number()
+    .min(0)
+    .max(100),
+}).required()
+
+const pkgJSONSchema = Joi.object({
+  c8: Joi.object({
+    branches: Joi.number()
+      .min(0)
+      .max(100),
+    lines: Joi.number()
+      .min(0)
+      .max(100),
+    functions: Joi.number()
+      .min(0)
+      .max(100),
+  }).optional(),
+  nyc: Joi.object({
+    branches: Joi.number()
+      .min(0)
+      .max(100),
+    lines: Joi.number()
+      .min(0)
+      .max(100),
+    functions: Joi.number()
+      .min(0)
+      .max(100),
+  }).optional(),
+}).required()
+
+const documentation = `<p>
+  Create a code coverage badge, based on thresholds stored in a
+  <a href="https://github.com/istanbuljs/nyc#common-configuration-options">.nycrc config file</a>
+  on GitHub.
+</p>`
+
+const validThresholds = ['branches', 'lines', 'functions']
+
+module.exports = class Nycrc extends ConditionalGithubAuthV3Service {
+  static get category() {
+    return 'coverage'
+  }
+
+  static get route() {
+    return {
+      base: 'nycrc',
+      // TODO: eventually add support for .yml and .yaml:
+      pattern: ':user/:repo',
+      queryParamSchema: Joi.object({
+        config: Joi.string()
+          .regex(/(.*\.nycrc)|(.*\.json$)/)
+          .default('.nycrc'),
+        // Allow the default threshold detection logic to be overridden, .e.g.,
+        // favoring lines over branches:
+        preferredThreshold: Joi.string()
+          .optional()
+          .allow(...validThresholds),
+      }).required(),
+    }
+  }
+
+  static get examples() {
+    return [
+      {
+        title: 'nycrc config on GitHub',
+        namedParams: { user: 'yargs', repo: 'yargs' },
+        queryParams: { config: '.nycrc', preferredThreshold: 'lines' },
+        staticPreview: this.render({ coverage: 92 }),
+        documentation,
+      },
+    ]
+  }
+
+  static get defaultBadgeData() {
+    return { label: 'min coverage' }
+  }
+
+  static render({ coverage }) {
+    return {
+      message: `${coverage.toFixed(0)}%`,
+      color: coveragePercentage(coverage),
+    }
+  }
+
+  extractThreshold(config, preferredThreshold) {
+    const { branches, lines } = config
+    if (preferredThreshold) {
+      if (!validThresholds.includes(preferredThreshold)) {
+        throw new InvalidParameter({
+          prettyMessage: `threshold must be "branches", "lines", or "functions"`,
+        })
+      }
+      if (!config[preferredThreshold]) {
+        throw new InvalidResponse({
+          prettyMessage: `"${preferredThreshold}" threshold missing`,
+        })
+      }
+      return config[preferredThreshold]
+    } else if (branches || lines) {
+      // We favor branches over lines for the coverage badge, if both
+      // thresholds are provided (as branches is the stricter requirement):
+      return branches || lines
+    } else {
+      throw new InvalidResponse({
+        prettyMessage: '"branches" or "lines" threshold missing',
+      })
+    }
+  }
+
+  async handle({ user, repo }, queryParams) {
+    const { config, preferredThreshold } = queryParams
+    let coverage
+    if (config.includes('package.json')) {
+      const pkgJson = await fetchJsonFromRepo(this, {
+        schema: pkgJSONSchema,
+        user,
+        repo,
+        branch: 'master',
+        filename: config,
+      })
+      const nycConfig = pkgJson.c8 || pkgJson.nyc
+      if (!nycConfig) {
+        throw new NotFound({
+          prettyMessage: 'no nyc or c8 stanza found',
+        })
+      } else {
+        coverage = this.extractThreshold(nycConfig, preferredThreshold)
+      }
+    } else {
+      coverage = this.extractThreshold(
+        await fetchJsonFromRepo(this, {
+          schema: nycrcSchema,
+          user,
+          repo,
+          branch: 'master',
+          filename: config,
+        }),
+        preferredThreshold
+      )
+    }
+    return this.constructor.render({ coverage })
+  }
+}

services/nycrc/nycrc.tester.js

@@ -0,0 +1,106 @@
+'use strict'
+
+const { isIntegerPercentage } = require('../test-validators')
+const t = (module.exports = require('../tester').createServiceTester())
+
+t.create('valid .nycrc')
+  .get('/yargs/yargs.json?config=.nycrc')
+  .expectBadge({ label: 'min coverage', message: isIntegerPercentage })
+
+t.create('.nycrc is default')
+  .get('/yargs/yargs.json')
+  .expectBadge({ label: 'min coverage', message: isIntegerPercentage })
+
+t.create('alternate threshold is specified')
+  .get('/yargs/yargs.json?preferredThreshold=lines')
+  .expectBadge({ label: 'min coverage', message: '100%' })
+
+t.create('invalid threshold is specified')
+  .get('/yargs/yargs.json?preferredThreshold=blerg')
+  .expectBadge({
+    label: 'min coverage',
+    message: 'threshold must be "branches", "lines", or "functions"',
+  })
+
+t.create('.nycrc in monorepo')
+  .get('/yargs/yargs.json?config=packages/foo/.nycrc.json')
+  .intercept(nock =>
+    nock('https://api.github.com')
+      .get('/repos/yargs/yargs/contents/packages/foo/.nycrc.json?ref=master')
+      .reply(200, {
+        content: Buffer.from(
+          JSON.stringify({
+            lines: 99,
+          })
+        ).toString('base64'),
+        encoding: 'base64',
+      })
+  )
+  .expectBadge({ label: 'min coverage', message: isIntegerPercentage })
+
+t.create('.nycrc with no thresholds')
+  .get('/yargs/yargs.json?config=.nycrc')
+  .intercept(nock =>
+    nock('https://api.github.com')
+      .get('/repos/yargs/yargs/contents/.nycrc?ref=master')
+      .reply(200, {
+        content: Buffer.from(
+          JSON.stringify({
+            reporter: 'foo',
+          })
+        ).toString('base64'),
+        encoding: 'base64',
+      })
+  )
+  .expectBadge({
+    label: 'min coverage',
+    message: '"branches" or "lines" threshold missing',
+  })
+
+t.create('package.json with nyc stanza')
+  .get('/yargs/yargs.json?config=package.json')
+  .intercept(nock =>
+    nock('https://api.github.com')
+      .get('/repos/yargs/yargs/contents/package.json?ref=master')
+      .reply(200, {
+        content: Buffer.from(
+          JSON.stringify({
+            nyc: {
+              lines: 99,
+            },
+          })
+        ).toString('base64'),
+        encoding: 'base64',
+      })
+  )
+  .expectBadge({ label: 'min coverage', message: isIntegerPercentage })
+
+t.create('package.json with nyc stanza, but no thresholds')
+  .get('/yargs/yargs.json?config=package.json')
+  .intercept(nock =>
+    nock('https://api.github.com')
+      .get('/repos/yargs/yargs/contents/package.json?ref=master')
+      .reply(200, {
+        content: Buffer.from(
+          JSON.stringify({
+            nyc: {},
+          })
+        ).toString('base64'),
+        encoding: 'base64',
+      })
+  )
+  .expectBadge({
+    label: 'min coverage',
+    message: '"branches" or "lines" threshold missing',
+  })
+
+t.create('package.json with no nyc stanza')
+  .get('/badges/shields.json?config=package.json')
+  .expectBadge({
+    label: 'min coverage',
+    message: 'no nyc or c8 stanza found',
+  })
+
+t.create('arbitrary JSON file, matching .nycrc format')
+  .get('/swellaby/nyc-config.json?config=partial-coverage.json')
+  .expectBadge({ label: 'min coverage', message: isIntegerPercentage })