Switch to hash.js from sha1 (#67)

* Switch to hash.js from sha1

Hash.js pulling just sha1 is 2.3k gzipped, while sha1 is 8k. Switch to save some bytes and align with what calypso uses.

* Add tests for hashed lookups

packages/i18n-calypso/lib/index.js

@@ -4,7 +4,7 @@
 var debug = require( 'debug' )( 'i18n-calypso' ),
 	Jed = require( 'jed' ),
 	moment = require( 'moment-timezone' ),
-	sha1 = require( 'sha1' ),
+	sha1 = require( 'hash.js/lib/hash/sha/1' ),
 	EventEmitter = require( 'events' ).EventEmitter,
 	interpolateComponents = require( 'interpolate-components' ).default,
 	LRU = require( 'lru' ),
@@ -201,16 +201,17 @@ I18N.prototype.setLocale = function( localeData ) {
 		var hashLength, minHashLength, maxHashLength, keyHash = localeData[ '' ][ 'key-hash' ];
 
 		var transform = function( string, hashLength ) {
-			if ( typeof hashCache[ hashLength + string ] !== 'undefined' ) {
-				return hashCache[ hashLength + string ];
+			const lookupPrefix = hashLength === false ? '' : String( hashLength );
+			if ( typeof hashCache[ lookupPrefix + string ] !== 'undefined' ) {
+				return hashCache[ lookupPrefix + string ];
 			}
-			var hash = sha1( string );
+			var hash = sha1().update( string ).digest('hex');
 
 			if ( hashLength ) {
-				return hashCache[ hashLength + string ] = hash.substr( 0, hashLength );
+				return hashCache[ lookupPrefix + string ] = hash.substr( 0, hashLength );
 			}
 
-			return hashCache[ hashLength + string ] = hash;
+			return hashCache[ lookupPrefix + string ] = hash;
 		};
 
 		var generateLookup = function( hashLength ) {

packages/i18n-calypso/package.json

@@ -24,6 +24,7 @@
     "create-react-class": "^15.6.2",
     "debug": "^3.1.0",
     "globby": "^6.1.0",
+    "hash.js": "^1.1.5",
     "interpolate-components": "1.1.1",
     "jed": "1.0.2",
     "jstimezonedetect": "1.0.5",
@@ -32,7 +33,6 @@
     "lru": "^3.1.0",
     "moment-timezone": "0.5.11",
     "react": "0.14.8 || ^15.5.0 || ^16.0.0",
-    "sha1": "^1.1.1",
     "xgettext-js": "^2.0.0"
   },
   "devDependencies": {

packages/i18n-calypso/test/index.js

@@ -328,4 +328,49 @@ describe( 'I18n', function() {
 			} );
 		} );
 	} );
+
+	describe( 'hashed locale data', function() {
+		it( 'should find keys when looked up by simple hash', function() {
+			i18n.setLocale( {
+				'': {
+					localeSlug: 'xx-pig-latin',
+					'key-hash': 'sha1'
+				},
+				'0f7d0d088b6ea936fb25b477722d734706fe8b40': [
+					null,
+					'implesa'
+				]
+			});
+			assert.equal( i18n.translate( 'simple' ), 'implesa' );
+		} );
+
+		it( 'should find keys when looked up by single length hash', function() {
+			i18n.setLocale( {
+				'': {
+					localeSlug: 'xx-pig-latin',
+					'key-hash': 'sha1-1'
+				},
+				'0': [
+					null,
+					'implesa'
+				]
+			});
+			assert.equal( i18n.translate( 'simple' ), 'implesa' );
+		} );
+
+		it( 'should find keys when looked up by multi length hash', function() {
+			i18n.setLocale( {
+				'': {
+					localeSlug: 'xx-pig-latin',
+					'key-hash': 'sha1-1-2'
+				},
+				'0': [ null,'implesa' ],
+				'78': [ null, 'edra' ],  // red has a sha1 of 78988010b890ce6f4d2136481f392787ec6d6106
+				'7d': [ null, 'reyga' ] // grey has a sha1 of 7d1f8f911da92c0ea535cad461fd773281a79638
+			});
+			assert.equal( i18n.translate( 'simple' ), 'implesa' );
+			assert.equal( i18n.translate( 'red' ), 'edra' );
+			assert.equal( i18n.translate( 'grey' ), 'reyga' );
+		} );
+	} );
 } );