.

node_modules/abab/lib/btoa.js

@@ -0,0 +1,66 @@
+"use strict";
+
+/**
+ * btoa() as defined by the HTML and Infra specs, which mostly just references
+ * RFC 4648.
+ */
+function btoa(s) {
+  let i;
+  // String conversion as required by Web IDL.
+  s = `${s}`;
+  // "The btoa() method must throw an "InvalidCharacterError" DOMException if
+  // data contains any character whose code point is greater than U+00FF."
+  for (i = 0; i < s.length; i++) {
+    if (s.charCodeAt(i) > 255) {
+      return null;
+    }
+  }
+  let out = "";
+  for (i = 0; i < s.length; i += 3) {
+    const groupsOfSix = [undefined, undefined, undefined, undefined];
+    groupsOfSix[0] = s.charCodeAt(i) >> 2;
+    groupsOfSix[1] = (s.charCodeAt(i) & 0x03) << 4;
+    if (s.length > i + 1) {
+      groupsOfSix[1] |= s.charCodeAt(i + 1) >> 4;
+      groupsOfSix[2] = (s.charCodeAt(i + 1) & 0x0f) << 2;
+    }
+    if (s.length > i + 2) {
+      groupsOfSix[2] |= s.charCodeAt(i + 2) >> 6;
+      groupsOfSix[3] = s.charCodeAt(i + 2) & 0x3f;
+    }
+    for (let j = 0; j < groupsOfSix.length; j++) {
+      if (typeof groupsOfSix[j] === "undefined") {
+        out += "=";
+      } else {
+        out += btoaLookup(groupsOfSix[j]);
+      }
+    }
+  }
+  return out;
+}
+
+/**
+ * Lookup table for btoa(), which converts a six-bit number into the
+ * corresponding ASCII character.
+ */
+function btoaLookup(idx) {
+  if (idx < 26) {
+    return String.fromCharCode(idx + "A".charCodeAt(0));
+  }
+  if (idx < 52) {
+    return String.fromCharCode(idx - 26 + "a".charCodeAt(0));
+  }
+  if (idx < 62) {
+    return String.fromCharCode(idx - 52 + "0".charCodeAt(0));
+  }
+  if (idx === 62) {
+    return "+";
+  }
+  if (idx === 63) {
+    return "/";
+  }
+  // Throw INVALID_CHARACTER_ERR exception here -- won't be hit in the tests.
+  return undefined;
+}
+
+module.exports = btoa;