🚩 Add strict flag

This change adds a `strict` flag to control whether we have the stricter
type checking introduced in #40

Strict mode will be off by default (to maintain compatibility with old
`json0` versions).

In order to add this flag, we also add a new `options` object to the
`type`. Strict mode is enabled on the type by setting the flag:

```js
type.options.strict = true
```

Note that `text0` will share the same options as `json0` (ie enabling
strict mode for `json0` also enables it for `text0`).

In this change we also tidy up some unused utility functions from a
previous commit.

Author: alecgibson

lib/json0.js

@@ -43,23 +43,14 @@ var clone = function(o) {
   return JSON.parse(JSON.stringify(o));
 };
 
-var validateListIndex = function(key) {
-  if (typeof key !== 'number')
-    throw new Error('List index must be a number');
-};
-
-var validateObjectKey = function (key) {
-  if (typeof key !== 'string')
-    throw new Error('Object key must be a number');
-};
-
 /**
  * JSON OT Type
  * @type {*}
  */
 var json = {
   name: 'json0',
-  uri: 'http://sharejs.org/types/JSONv0'
+  uri: 'http://sharejs.org/types/JSONv0',
+  options: require('./options')
 };
 
 // You can register another OT type as a subtype in a JSON document using
@@ -172,10 +163,10 @@ json.apply = function(snapshot, op) {
       elem = elem[key];
       key = p;
 
-      if (isArray(elem) && typeof key !== 'number')
+      if (json.options.strict && isArray(elem) && typeof key !== 'number')
         throw new Error('List index must be a number');
 
-      if (isObject(elem) && typeof key !== 'string')
+      if (json.options.strict && isObject(elem) && typeof key !== 'string')
         throw new Error('Object key must be a string');
 
       if (parent == null)
@@ -191,7 +182,7 @@ json.apply = function(snapshot, op) {
       if (typeof elem[key] != 'number')
         throw new Error('Referenced element not a number');
 
-      if (typeof c.na !== 'number')
+      if (json.options.strict && typeof c.na !== 'number')
         throw new Error('Number addition is not a number');
 
       elem[key] += c.na;
@@ -219,7 +210,7 @@ json.apply = function(snapshot, op) {
 
     // List move
     else if (c.lm !== void 0) {
-      if (typeof c.lm !== 'number')
+      if (json.options.strict && typeof c.lm !== 'number')
         throw new Error('List move target index must be a number');
 
       json.checkList(elem);

lib/options.js

@@ -0,0 +1,3 @@
+module.exports = {
+  strict: false
+};

lib/text0.js

@@ -24,6 +24,7 @@
 var text = module.exports = {
   name: 'text0',
   uri: 'http://sharejs.org/types/textv0',
+  options: require('./options'),
   create: function(initial) {
     if ((initial != null) && typeof initial !== 'string') {
       throw new Error('Initial data must be a string');
@@ -61,7 +62,7 @@ text.apply = function(snapshot, op) {
   var deleted;
 
   var type = typeof snapshot;
-  if (type !== 'string')
+  if (text.options.strict && type !== 'string')
     throw new Error('text0 operations cannot be applied to type: ' + type);
 
   checkValidOp(op);

test/json0.coffee

@@ -64,11 +64,18 @@ genTests = (type) ->
       c_s = type.apply leftHas, right_
       assert.deepEqual s_c, c_s
 
-    it 'throws when adding a string to a number', ->
-      assert.throws -> type.apply 1, [{p: [], na: 'a'}]
+    describe 'strict', ->
+      beforeEach ->
+        type.options.strict = true
 
-    it 'throws when adding a number to a string', ->
-      assert.throws -> type.apply 'a', [{p: [], na: 1}]
+      afterEach ->
+        type.options.strict = false
+
+      it 'throws when adding a string to a number', ->
+        assert.throws -> type.apply 1, [{p: [], na: 'a'}]
+
+      it 'throws when adding a number to a string', ->
+        assert.throws -> type.apply 'a', [{p: [], na: 1}]
 
   # Strings should be handled internally by the text type. We'll just do some basic sanity checks here.
   describe 'string', ->
@@ -138,23 +145,30 @@ genTests = (type) ->
         assert.deepEqual ['a', 'b', 'c'], type.apply ['b', 'a', 'c'], [{p:[1], lm:0}]
         assert.deepEqual ['a', 'b', 'c'], type.apply ['b', 'a', 'c'], [{p:[0], lm:1}]
 
-      it 'throws when keying a list replacement with a string', ->
-        assert.throws -> type.apply ['a', 'b', 'c'], [{p: ['0'], li: 'x', ld: 'a'}]
+    describe 'strict', ->
+      beforeEach ->
+        type.options.strict = true
+
+      afterEach ->
+        type.options.strict = false
 
-      it 'throws when keying a list insertion with a string', ->
-        assert.throws -> type.apply ['a', 'b', 'c'], [{p: ['0'], li: 'x'}]
+        it 'throws when keying a list replacement with a string', ->
+          assert.throws -> type.apply ['a', 'b', 'c'], [{p: ['0'], li: 'x', ld: 'a'}]
 
-      it 'throws when keying a list deletion with a string', ->
-        assert.throws -> type.apply ['a', 'b', 'c'], [{p: ['0'], ld: 'a'}]
+        it 'throws when keying a list insertion with a string', ->
+          assert.throws -> type.apply ['a', 'b', 'c'], [{p: ['0'], li: 'x'}]
 
-      it 'throws when keying a list move with a string', ->
-        assert.throws -> type.apply ['a', 'b', 'c'], [{p: ['0'], lm: 0}]
+        it 'throws when keying a list deletion with a string', ->
+          assert.throws -> type.apply ['a', 'b', 'c'], [{p: ['0'], ld: 'a'}]
 
-      it 'throws when specifying a string as a list move target', ->
-        assert.throws -> type.apply ['a', 'b', 'c'], [{p: [1], lm: '0'}]
+        it 'throws when keying a list move with a string', ->
+          assert.throws -> type.apply ['a', 'b', 'c'], [{p: ['0'], lm: 0}]
 
-      it 'throws when an array index part-way through the path is a string', ->
-        assert.throws -> type.apply {arr:[{x:'a'}]}, [{p:['arr', '0', 'x'], od: 'a'}]
+        it 'throws when specifying a string as a list move target', ->
+          assert.throws -> type.apply ['a', 'b', 'c'], [{p: [1], lm: '0'}]
+
+        it 'throws when an array index part-way through the path is a string', ->
+          assert.throws -> type.apply {arr:[{x:'a'}]}, [{p:['arr', '0', 'x'], od: 'a'}]
 
       ###
       'null moves compose to nops', ->
@@ -418,14 +432,21 @@ genTests = (type) ->
       assert.deepEqual [], type.transform [{p:['k'], od:'x'}], [{p:['k'], od:'x'}], 'left'
       assert.deepEqual [], type.transform [{p:['k'], od:'x'}], [{p:['k'], od:'x'}], 'right'
 
-    it 'throws when the insertion key is a number', ->
-      assert.throws -> type.apply {'1':'a'}, [{p:[2], oi: 'a'}]
+    describe 'strict', ->
+      beforeEach ->
+        type.options.strict = true
+
+      afterEach ->
+        type.options.strict = false
+
+      it 'throws when the insertion key is a number', ->
+        assert.throws -> type.apply {'1':'a'}, [{p:[2], oi: 'a'}]
 
-    it 'throws when the deletion key is a number', ->
-      assert.throws -> type.apply {'1':'a'}, [{p:[1], od: 'a'}]
+      it 'throws when the deletion key is a number', ->
+        assert.throws -> type.apply {'1':'a'}, [{p:[1], od: 'a'}]
 
-    it 'throws when an object key part-way through the path is a number', ->
-      assert.throws -> type.apply {'1': {x: 'a'}}, [{p:[1, 'x'], od: 'a'}]
+      it 'throws when an object key part-way through the path is a number', ->
+        assert.throws -> type.apply {'1': {x: 'a'}}, [{p:[1, 'x'], od: 'a'}]
 
   describe 'randomizer', ->
     @timeout 20000