fix: Double precision EJSON fix and Spec update

Reduce the precision outputted for Double types

NODE-2431

Author: nbbeeken

etc/update-spec-tests.sh

@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+
+# This script is used to fetch the latest JSON tests for the BSON spec.
+# It puts the tests in the direcory $spec_root It should be run from the root of the repository.
+
+set -o errexit
+set -o nounset
+
+if [ ! -d ".git" ]; then
+    echo "$0: This script must be run from the root of the repository" >&2
+    exit 1
+fi
+
+spec_root="test"
+
+tmpdir=$(mktemp -d -t spec_testsXXXX)
+curl -sL https://github.com/mongodb/specifications/archive/master.zip -o "$tmpdir/specs.zip"
+unzip -d "$tmpdir" "$tmpdir/specs.zip" > /dev/null
+
+mkdir -p "$spec_root/bson-corpus"
+rsync -ah "$tmpdir/specifications-master/source/bson-corpus/tests/" "$spec_root/bson-corpus" --delete
+
+rm -rf "$tmpdir"

lib/bson/double.js

@@ -1,8 +1,26 @@
 'use strict';
 
 function toExtendedJSON(obj, options) {
-  if (options && options.relaxed && isFinite(obj.value)) return obj.value;
-  return { $numberDouble: obj.value.toString() };
+  if (options && (options.legacy || (options.relaxed && isFinite(obj.value)))) {
+    return obj.value;
+  }
+  // NOTE: JavaScript has +0 and -0, apparently to model limit calculations. If a user
+  // explicitly provided `-0` then we need to ensure the sign makes it into the output
+  if (Object.is(Math.sign(obj.value), -0)) {
+    return { $numberDouble: `-${obj.value.toFixed(1)}` };
+  }
+
+  var numberDouble;
+  if (Number.isInteger(obj.value)) {
+    numberDouble = obj.value.toFixed(1);
+    if (numberDouble.length >= 13) {
+      numberDouble = obj.value.toExponential(13).toUpperCase();
+    }
+  } else {
+    numberDouble = obj.value.toString();
+  }
+
+  return { $numberDouble: numberDouble };
 }
 
 function fromExtendedJSON(BSON, doc, options) {

package-lock.json

@@ -41,7 +41,7 @@
     "eslint-plugin-prettier": "^2.3.1",
     "istanbul": "^0.4.5",
     "mocha": "^3.4.1",
-    "mongodb": "^2.2.27",
+    "mongodb": "^3.5",
     "prettier": "~1.12.0",
     "rollup": "^0.56.2",
     "rollup-plugin-babel": "^3.0.3",

package.json

@@ -14,16 +14,22 @@
             "canonical_extjson": "{\"a\" : [{\"$numberInt\": \"10\"}]}"
         },
         {
-            "description": "Single Element Array with index set incorrectly",
+            "description": "Single Element Array with index set incorrectly to empty string",
             "degenerate_bson": "130000000461000B00000010000A0000000000",
             "canonical_bson": "140000000461000C0000001030000A0000000000",
             "canonical_extjson": "{\"a\" : [{\"$numberInt\": \"10\"}]}"
         },
         {
-            "description": "Single Element Array with index set incorrectly",
+            "description": "Single Element Array with index set incorrectly to ab",
             "degenerate_bson": "150000000461000D000000106162000A0000000000",
             "canonical_bson": "140000000461000C0000001030000A0000000000",
             "canonical_extjson": "{\"a\" : [{\"$numberInt\": \"10\"}]}"
+        },
+        {
+            "description": "Multi Element Array with duplicate indexes",
+            "degenerate_bson": "1b000000046100130000001030000a000000103000140000000000",
+            "canonical_bson": "1b000000046100130000001030000a000000103100140000000000",
+            "canonical_extjson": "{\"a\" : [{\"$numberInt\": \"10\"}, {\"$numberInt\": \"20\"}]}"
         }
     ],
     "decodeErrors": [

test/bson-corpus/array.json

@@ -25,6 +25,12 @@
             "description" : "Y10K",
             "canonical_bson" : "1000000009610000DC1FD277E6000000",
             "canonical_extjson" : "{\"a\":{\"$date\":{\"$numberLong\":\"253402300800000\"}}}"
+        },
+        {
+            "description": "leading zero ms",
+            "canonical_bson": "10000000096100D1D6D6CC3B01000000",
+            "relaxed_extjson": "{\"a\" : {\"$date\" : \"2012-12-24T12:15:30.001Z\"}}",
+            "canonical_extjson": "{\"a\" : {\"$date\" : {\"$numberLong\" : \"1356351330001\"}}}"
         }
     ],
     "decodeErrors": [