Try djb2 hash

Author: lewisl9029

src/basic/hash-murmur.js

@@ -0,0 +1,88 @@
+// Copied from https://github.com/emotion-js/emotion/blob/master/packages/hash/src/index.js
+
+const murmur2 = (str) => {
+  // 'm' and 'r' are mixing constants generated offline.
+  // They're not really 'magic', they just happen to work well.
+
+  // const m = 0x5bd1e995;
+  // const r = 24;
+
+  // Initialize the hash
+
+  var h = 0;
+
+  // Mix 4 bytes at a time into the hash
+
+  var k,
+    i = 0,
+    len = str.length;
+  for (; len >= 4; ++i, len -= 4) {
+    k =
+      (str.charCodeAt(i) & 0xff) |
+      ((str.charCodeAt(++i) & 0xff) << 8) |
+      ((str.charCodeAt(++i) & 0xff) << 16) |
+      ((str.charCodeAt(++i) & 0xff) << 24);
+
+    k =
+      /* Math.imul(k, m): */
+      (k & 0xffff) * 0x5bd1e995 + (((k >>> 16) * 0xe995) << 16);
+    k ^= /* k >>> r: */ k >>> 24;
+
+    h =
+      /* Math.imul(k, m): */
+      ((k & 0xffff) * 0x5bd1e995 + (((k >>> 16) * 0xe995) << 16)) ^
+      /* Math.imul(h, m): */
+      ((h & 0xffff) * 0x5bd1e995 + (((h >>> 16) * 0xe995) << 16));
+  }
+
+  // Handle the last few bytes of the input array
+
+  switch (len) {
+    case 3:
+      h ^= (str.charCodeAt(i + 2) & 0xff) << 16;
+    case 2:
+      h ^= (str.charCodeAt(i + 1) & 0xff) << 8;
+    case 1:
+      h ^= str.charCodeAt(i) & 0xff;
+      h =
+        /* Math.imul(h, m): */
+        (h & 0xffff) * 0x5bd1e995 + (((h >>> 16) * 0xe995) << 16);
+  }
+
+  // Do a few final mixes of the hash to ensure the last few
+  // bytes are well-incorporated.
+
+  h ^= h >>> 13;
+  h =
+    /* Math.imul(h, m): */
+    (h & 0xffff) * 0x5bd1e995 + (((h >>> 16) * 0xe995) << 16);
+
+  return ((h ^ (h >>> 15)) >>> 0).toString(36);
+}
+
+// Copied from https://github.com/styled-components/styled-components/blob/master/packages/styled-components/src/utils/hash.js
+
+const SEED = 5381;
+
+// When we have separate strings it's useful to run a progressive
+// version of djb2 where we pretend that we're still looping over
+// the same string
+const phash = (h, x) => {
+  let i = x.length;
+
+  while (i) {
+    h = (h * 33) ^ x.charCodeAt(--i);
+  }
+
+  return h;
+};
+
+// This is a djb2 hashing function
+const hash = (x) => {
+  return phash(SEED, x);
+};
+
+// switch between readable vs faster & smaller classnames depending on environment
+const readableHash = (value) => CSS.escape(value).replace(/\\./g, '_')
+
+export default murmur2

src/basic/hash.js

@@ -1,67 +1,4 @@
-// Copied from https://github.com/emotion-js/emotion/blob/master/packages/hash/src/index.js
-
-const murmur2 = (str) => {
-  // 'm' and 'r' are mixing constants generated offline.
-  // They're not really 'magic', they just happen to work well.
-
-  // const m = 0x5bd1e995;
-  // const r = 24;
-
-  // Initialize the hash
-
-  var h = 0;
-
-  // Mix 4 bytes at a time into the hash
-
-  var k,
-    i = 0,
-    len = str.length;
-  for (; len >= 4; ++i, len -= 4) {
-    k =
-      (str.charCodeAt(i) & 0xff) |
-      ((str.charCodeAt(++i) & 0xff) << 8) |
-      ((str.charCodeAt(++i) & 0xff) << 16) |
-      ((str.charCodeAt(++i) & 0xff) << 24);
-
-    k =
-      /* Math.imul(k, m): */
-      (k & 0xffff) * 0x5bd1e995 + (((k >>> 16) * 0xe995) << 16);
-    k ^= /* k >>> r: */ k >>> 24;
-
-    h =
-      /* Math.imul(k, m): */
-      ((k & 0xffff) * 0x5bd1e995 + (((k >>> 16) * 0xe995) << 16)) ^
-      /* Math.imul(h, m): */
-      ((h & 0xffff) * 0x5bd1e995 + (((h >>> 16) * 0xe995) << 16));
-  }
-
-  // Handle the last few bytes of the input array
-
-  switch (len) {
-    case 3:
-      h ^= (str.charCodeAt(i + 2) & 0xff) << 16;
-    case 2:
-      h ^= (str.charCodeAt(i + 1) & 0xff) << 8;
-    case 1:
-      h ^= str.charCodeAt(i) & 0xff;
-      h =
-        /* Math.imul(h, m): */
-        (h & 0xffff) * 0x5bd1e995 + (((h >>> 16) * 0xe995) << 16);
-  }
-
-  // Do a few final mixes of the hash to ensure the last few
-  // bytes are well-incorporated.
-
-  h ^= h >>> 13;
-  h =
-    /* Math.imul(h, m): */
-    (h & 0xffff) * 0x5bd1e995 + (((h >>> 16) * 0xe995) << 16);
-
-  return ((h ^ (h >>> 15)) >>> 0).toString(36);
-}
-
-// Copied from https://github.com/styled-components/styled-components/blob/master/packages/styled-components/src/utils/hash.js
-
+// Copied from https://github.com/styled-components/styled-components/blob/3ee575eddf804e4bf460f1cadb5890db7ae2f5cf/packages/styled-components/src/utils/hash.ts#L6
 const SEED = 5381;
 
 // When we have separate strings it's useful to run a progressive
@@ -78,11 +15,8 @@ const phash = (h, x) => {
 };
 
 // This is a djb2 hashing function
-const hash = (x) => {
+const hash = x => {
   return phash(SEED, x);
 };
 
-// switch between readable vs faster & smaller classnames depending on environment
-const readableHash = (value) => CSS.escape(value).replace(/\\./g, '_')
-
-export default murmur2
+export default hash;