fix: drop special shebang handling

.nycrc

@@ -7,6 +7,6 @@
     "text"
   ],
   "lines": 99.5,
-  "branches": "94",
+  "branches": "92",
   "statements": "99.5"
-}
+}

lib/source.js

@@ -206,8 +206,10 @@ function originalPositionTryBoth (sourceMap, line, column) {
   return original
 }
 
+// Not required since Node 13, see: https://github.com/nodejs/node/pull/27375
+const isPrerNode13 = /^v1[0-2]\./u.test(process.version)
 function getShebangLength (source) {
-  if (source.indexOf('#!') === 0) {
+  if (isPrerNode13 && source.indexOf('#!') === 0) {
     const match = source.match(/(?<shebang>#!.*)/)
     if (match) {
       return match.groups.shebang.length

package.json

@@ -32,6 +32,7 @@
   "devDependencies": {
     "@types/node": "^12.7.11",
     "c8": "^7.2.1",
+    "semver": "^7.3.2",
     "should": "13.2.3",
     "standard": "^14.3.1",
     "tap": "^14.10.8"

test/fixtures/shebang.js

@@ -1,5 +1,6 @@
 module.exports = {
   describe: 'shebang',
+  maxNodeVersion: 'v13.0.0',
   coverageV8: {
     "scriptId": "56",
     "url": "./test/fixtures/scripts/shebang.js",

test/utils/run-fixture.js

@@ -2,13 +2,19 @@
 
 const toIstanbul = require('../../')
 const t = require('tap')
+const semver = require('semver')
 
 t.mochaGlobals()
 require('should')
 
 module.exports = async (fixture) => {
   const script = toIstanbul(fixture.coverageV8.url)
   await script.load()
+  if (fixture.maxNodeVersion && !semver.lt(process.version, fixture.maxNodeVersion)) {
+    console.info(`skipping "${fixture.describe}" fixture maxNodeVersion = ${fixture.maxNodeVersion}`)
+    return
+  }
+
   script.applyCoverage(fixture.coverageV8.functions)
 
   let coverageIstanbul = script.toIstanbul()