- typeOf no longer throws

- removed Without Type Checking example that used undocumented internals
- removed info blurb about only accepting component classes for additional safety

docs/advanced/type-validation.md

@@ -2,7 +2,7 @@ In certain situations, such as when building reusable and customizable component
 
 To facilitate safer development for these kinds of situations, Roact provides the `Roact.typeOf` and `Roact.isComponent` functions to help validate these objects.
 
-## Without Type Validation
+## Roact Object Type Validation
 
 Suppose we want to write a `Header` component with a prop for the title child element:
 ```lua
@@ -19,23 +19,7 @@ function Header:render()
 end
 ```
 
-Now suppose we want to validate that `title` is actually an element using [validateProps](../../api-reference/#validateprops). Without a type checking function, `title` must be queried to check for characteristics of an element:
-```lua
-Header.validateProps = function()
-	local title = props.title
-
-	if title.component then
-		return true
-	end
-
-	return false, tostring(Header) .. " prop title is not an element"
-end
-```
-This approach is fragile, since it relies on undocumented internals.
-
-## Roact Object Type Validation
-
-With `Roact.typeOf` we can be certain we have a Roact Element:
+Now suppose we want to validate that `title` is actually an element using [validateProps](../../api-reference/#validateprops). With `Roact.typeOf` we can be certain we have a Roact Element:
 ```lua
 Header.validateProps = function()
 	local title = props.title
@@ -44,7 +28,7 @@ Header.validateProps = function()
 		return true
 	end
 
-	return false, tostring(Header) .. " prop title is not an element"
+	return false, "prop title is not an element"
 end
 ```
 
@@ -62,7 +46,7 @@ Header.validateProps = function()
 		return true
 	end
 
-	return false, tostring(Header) .. " prop title can not be an element"
+	return false, "prop title can not be an element"
 end
 
 function Header:render()
@@ -75,7 +59,4 @@ function Header:render()
 		})
 	})
 end
-```
-
-!!! info
-	Because strings (hosts) and functions are valid component types, `Roact.isComponent` is less safe than `Roact.typeOf`. If safety is paramount, consider only allowing component classes, and checking that the `typeOf` the prop is `Roact.Type.StatefulComponentClass`.
+```

docs/api-reference.md

@@ -174,7 +174,7 @@ end
 Roact.typeOf(roactObject) -> Roact.Type
 ```
 
-Returns the [Roact.Type](#roacttype) of the passed in Roact object
+Returns the [Roact.Type](#roacttype) of the passed in Roact object, or `nil` if the input is not a Roact object.
 
 ---
 

src/Type.lua

@@ -41,6 +41,10 @@ function TypeInternal.of(value)
 end
 
 function TypeInternal.nameOf(type)
+	if typeof(type) ~= "userdata" then
+		return nil
+	end
+
 	return TypeNames[type]
 end
 

src/TypeMirror.lua

@@ -48,12 +48,6 @@ local Mirror = {
 	end,
 }
 
-setmetatable(Mirror, {
-	__tostring = function()
-		return "TypeMirror"
-	end
-})
-
 strict(Mirror, "TypeMirror")
 
 return Mirror

src/TypeMirror.spec.lua

@@ -33,13 +33,13 @@ return function()
 	end)
 
 	describe("typeOf", function()
-		it("should throw if the value is not a valid type", function()
-			expect(pcall(Mirror.typeOf, 1)).to.equal(false)
-			expect(pcall(Mirror.typeOf, true)).to.equal(false)
-			expect(pcall(Mirror.typeOf, "test")).to.equal(false)
-			expect(pcall(Mirror.typeOf, print)).to.equal(false)
-			expect(pcall(Mirror.typeOf, {})).to.equal(false)
-			expect(pcall(Mirror.typeOf, newproxy(true))).to.equal(false)
+		it("should return nil if the value is not a valid type", function()
+			expect(Mirror.typeOf(1)).to.equal(nil)
+			expect(Mirror.typeOf(true)).to.equal(nil)
+			expect(Mirror.typeOf"test").to.equal(nil)
+			expect(Mirror.typeOf(print)).to.equal(nil)
+			expect(Mirror.typeOf({})).to.equal(nil)
+			expect(Mirror.typeOf(newproxy(true))).to.equal(nil)
 		end)
 
 		it("should return the assigned type", function()