initial commit

node_modules/postcss-url/src/lib/hash.js

@@ -0,0 +1,54 @@
+'use strict';
+
+const crypto = require('crypto');
+const xxh = require('xxhashjs');
+const HEXBASE = 16;
+
+const defaultHashOptions = {
+    method: 'xxhash32',
+    shrink: 8,
+    append: false
+};
+
+const getxxhash = (content, options) => {
+    const hashFunc = options.method === 'xxhash32' ? xxh.h32 : xxh.h64;
+    const seed = 0;
+
+    return hashFunc(seed)
+        .update(content)
+        .digest()
+        .toString(HEXBASE);
+};
+
+const getHash = (content, options) => {
+    if (options.method && typeof options.method === 'function') {
+        return options.method(content);
+    }
+
+    if (options.method && options.method.indexOf('xxhash') === 0) {
+        return getxxhash(content, options);
+    }
+
+    try {
+        const hashFunc = crypto.createHash(options.method);
+
+        return hashFunc.update(content)
+            .digest('hex');
+    } catch (e) {
+        return null;
+    }
+};
+
+module.exports = function(content, options) {
+    options = options || defaultHashOptions;
+
+    let hash = getHash(content, options);
+
+    if (hash == null) {
+        // bad hash method; fallback to defaults
+        // TODO: warning/error reporting?
+        hash = getHash(content, defaultHashOptions);
+    }
+
+    return options.shrink ? hash.substr(0, options.shrink) : hash;
+};