hack around lack of export on windows

.gitignore

@@ -4,3 +4,4 @@ node_modules
 dist
 _actual
 coverage
+.commithash

gobblefile.js

@@ -2,11 +2,18 @@ var gobble = require( 'gobble' );
 var fs = require( 'fs' );
 
 var version = require( './package.json' ).version;
+var commitHash = (function () {
+	try {
+		return fs.readFileSync( '.commithash', 'utf-8' );
+	} catch ( err ) {
+		return 'unknown';
+	}
+})();
 
 var banner = fs.readFileSync( 'src/banner.js' ).toString()
 	.replace( '${version}', version )
 	.replace( '${time}', new Date() )
-	.replace( '${commitHash}', process.env.COMMIT_HASH || 'unknown' );
+	.replace( '${commitHash}', commitHash );
 
 var src = gobble( 'src' );
 

package.json

@@ -14,7 +14,7 @@
     "test-coverage": "rm -rf coverage/* && istanbul cover --report json node_modules/.bin/_mocha -- -u exports -R spec test/test.js",
     "posttest-coverage": "remap-istanbul -i coverage/coverage-final.json -o coverage/coverage-remapped.json -b dist && remap-istanbul -i coverage/coverage-final.json -o coverage/coverage-remapped.lcov -t lcovonly -b dist && remap-istanbul -i coverage/coverage-final.json -o coverage/coverage-remapped -t html -b dist",
     "ci": "npm run test-coverage && codecov < coverage/coverage-remapped.lcov",
-    "build": "export COMMIT_HASH=`git rev-parse HEAD` && gobble build -f dist",
+    "build": "git rev-parse HEAD > .commithash && gobble build -f dist",
     "prepublish": "npm test",
     "lint": "eslint src"
   },