feat: allow passing --from filename, closes #1

Author: bahmutov

README.md

@@ -11,5 +11,13 @@ npx check-coverage main.js
 npx only-covered foo.js bar.js
 ```
 
+## only-covered
+
+By default `only-covered` script reads `.nyc_output/out.json` file from the current working directory. You can specify a different file using `--from` parameter
+
+```shell
+only-covered --from examples/exclude-files/coverage/coverage-final.json main.js
+```
+
 [ci image]: https://github.com/bahmutov/check-code-coverage/workflows/ci/badge.svg?branch=master
 [ci url]: https://github.com/bahmutov/check-code-coverage/actions

bin/check-coverage.js

@@ -1,4 +1,5 @@
 #!/usr/bin/env node
+// @ts-check
 const { join } = require('path')
 
 const filename = process.argv[2]

bin/only-covered.js

@@ -1,8 +1,14 @@
 #!/usr/bin/env node
-const { join } = require('path')
+// @ts-check
+const { join, resolve } = require('path')
 const _ = require('lodash')
+const arg = require('arg')
 
-const filenames = process.argv.slice(2)
+const args = arg({
+  '--from': String, // input filename, by default ".nyc_output/out.json"
+})
+
+const filenames = args._
 if (!filenames.length) {
   console.error('Usage: node %s <file name 1> <file name 2>', __filename)
   process.exit(1)
@@ -11,7 +17,10 @@ if (!filenames.length) {
 const shouldBeCovered = filepath =>
   filenames.some(name => filepath.endsWith(name))
 
-const coverageFilename = join(process.cwd(), '.nyc_output', 'out.json')
+const fromFilename = args['--from'] || join('.nyc_output', 'out.json')
+const coverageFilename = resolve(fromFilename)
+console.log('reading coverage results from %s', coverageFilename)
+
 const coverage = require(coverageFilename)
 
 const coveredFilepaths = Object.keys(coverage).map(name => coverage[name].path)

package-lock.json

@@ -34,6 +34,7 @@
     "semantic-release": "^17.0.4"
   },
   "dependencies": {
+    "arg": "4.1.3",
     "lodash": "4.17.15"
   }
 }