using existing format-file-size; fixing nits with progress output

clients/fs/package.json

@@ -22,7 +22,9 @@
     "babel-plugin-transform-runtime": "^6.6.0",
     "babel-preset-es2015": "6.6.0",
     "babel-preset-react": "6.5.0",
-    "flow-bin": "^0.23.0"
+    "flow-bin": "^0.23.0",
+    "chai": "3.5.0",
+    "mocha": "2.4.5"
   },
   "scripts": {
     "start": "babel -d dist -w src",

clients/fs/src/format-file-size-test.js

@@ -0,0 +1,46 @@
+// @flow
+
+import {assert} from 'chai';
+import {suite, test} from 'mocha';
+import formatFileSize from './format-file-size.js';
+
+suite('spread-sheet-number', () => {
+
+  function doTest(n, s) {
+    test(s, () => {
+      assert.equal(formatFileSize(n), s);
+    });
+  }
+
+  doTest(0, '0B');
+  doTest(1, '1B');
+  doTest(2, '2B');
+  doTest(123, '123B');
+  doTest(1023, '1023B');
+  doTest(1024, '1KB');
+  doTest(1025, '1KB');
+  doTest(1.5 * 1024, '1.5KB');
+  doTest(1.2345 * 1024, '1.2KB');
+
+  const K = 1024;
+  const M = 1024 * K;
+  const G = 1024 * M;
+  const T = 1024 * G;
+  const P = 1024 * T;
+
+  doTest(.95 * M, '972.8KB');
+  doTest(M, '1MB');
+  doTest(1.23 * M, '1.2MB');
+
+  doTest(.95 * G, '972.8MB');
+  doTest(G, '1GB');
+  doTest(1.23 * G, '1.2GB');
+
+  doTest(.95 * T, '972.8GB');
+  doTest(T, '1TB');
+  doTest(1.23 * T, '1.2TB');
+
+  doTest(.95 * P, '972.8TB');
+  doTest(P, '1PB');
+  doTest(1.23 * P, '1.2PB');
+});

clients/fs/src/format-file-size.js

@@ -0,0 +1,14 @@
+// @flow
+
+const units = ['', 'K', 'M', 'G', 'T', 'P'];
+
+export default function formatFileSize(n: number): string {
+  if (n < 1) {
+    return n + 'B';
+  }
+
+  const exp = Math.min(Math.floor(Math.log(n) / Math.log(1024)), units.length - 1);
+  n = Number((n / Math.pow(1024, exp)).toFixed(1));
+
+  return n + units[exp] + 'B';
+}

clients/fs/src/main.js

@@ -3,6 +3,7 @@
 import fs from 'mz/fs';
 import path from 'path';
 import argv from 'yargs';
+import formatFileSize from './format-file-size.js';
 import {
   newMapOfStringToRefOfDirectoryEntry,
   Directory,
@@ -125,24 +126,10 @@ function processBlob(p: string, store: DataStore): Promise<RefValue<NomsBlob>> {
   });
 }
 
-function humanFileSize(bytes, si) {
-  const thresh = si ? 1000 : 1024;
-  if (Math.abs(bytes) < thresh) {
-    return bytes + ' B';
-  }
-  const units = si
-    ? ['kB','MB','GB','TB','PB','EB','ZB','YB']
-    : ['KiB','MiB','GiB','TiB','PiB','EiB','ZiB','YiB'];
-  let u = -1;
-  do {
-    bytes /= thresh;
-    ++u;
-  } while (Math.abs(bytes) >= thresh && u < units.length - 1);
-  return bytes.toFixed(1) + ' ' + units[u];
-}
-
 function updateProgress() {
-  process.stdout.write(`\r${numFilesComplete} of ${numFilesFound} entries processed... ${humanFileSize(sizeFilesComplete,true)} of ${humanFileSize(sizeFilesFound,true)} contents processed`);  // eslint-disable-line max-len
+  process.stdout.write(`\r${numFilesComplete} of ${numFilesFound} entries \
+(${formatFileSize(sizeFilesComplete)} of ${formatFileSize(sizeFilesFound)}) \
+processed...`);
 }
 
 function parseArgs() {