SkValue: implementation, unit test

src/core/SkValue.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkValue_DEFINED
 #define SkValue_DEFINED
 
 #include "SkTypes.h"
 #include <functional>
 
+class SkData;
+
 class SkValue {
 public:
     enum Type : uint32_t {
         // 0-255 are reserved for built-in SkValue types.
         Null,
         Byte , S16 , U16 , S32 , U32 , S64 , U64 , F32 , F64 ,
         Bytes, S16s, U16s, S32s, U32s, S64s, U64s, F32s, F64s,
         Array,
 
+        kMaxBuiltin = 0xFF,
         // 256-2147483647 may be used by Skia for public Object types.
 
+        Matrix,
 
-        // 2147483648+ won't be used by Skia.  They're open for client-specific use, testing, etc.
+        kMaxPublicObject = 0x7FFFFFFF,
+        // 2147483648+ won't be used by Skia.  They're open for
+        // client-specific use, testing, etc.
     };
 
-    enum Key : uint32_t {
-        // Each Object type may define its own namespace of Key values,
-        // so there are no pre-defined Keys here.
-        //
-        // This is just a reminder that they must fit in a uint32_t,
-        // and that their namespace is distinct from other uint32_ts (e.g. Type).
-    };
+    // Each Object type may define its own namespace of Key values,
+    // so there are no pre-defined Keys here.
+    //
+    // This is just a reminder that they must fit in a uint32_t,
+    // and that their namespace is distinct from other uint32_ts (e.g. Type).
+    typedef uint32_t Key;
 
     SkValue();
     SkValue(const SkValue&);
     SkValue(SkValue&&);
 
     SkValue& operator=(const SkValue&);
     SkValue& operator=(SkValue&&);
 
     ~SkValue();
 
     static SkValue FromS32(int32_t);
     static SkValue FromU32(uint32_t);
     static SkValue FromF32(float);
-    static SkValue FromBytes(const void*, size_t);  // Copies.
+    static SkValue FromBytes(SkData*);
+    static SkValue FromU16s(SkData*);
+    static SkValue FromU32s(SkData*);
+    static SkValue FromF32s(SkData*);
+    static SkValue ValueArray();
     static SkValue Object(Type);
 
-    Type type() const;
+    Type type() const { return fType; }
 
     // These remaining methods may assert they're called on a value of the appropriate type.
 
     int32_t  s32() const;
     uint32_t u32() const;
     float    f32() const;
+    SkData* bytes() const;
+    bool isData() const {

[mtklein, 2016/01/20 14:20:59]

private?

[hal.canary, 2016/01/20 15:14:35]

done

+        return Bytes == fType || U16s == fType || U32s == fType || F32s == fType;
+    }
+    const uint16_t* u16s(int* count) const;
+    const uint32_t* u32s(int* count) const;
+    const float*    f32s(int* count) const;
 
-    const void* bytes() const;
-    size_t      count() const;
-
+    // Object
+    bool isObject() const { return fType > kMaxBuiltin; }

[mtklein, 2016/01/20 14:20:59]

private?

[hal.canary, 2016/01/20 15:14:35]

done

     void set(Key, SkValue);
-    const SkValue* get(Key) const;
     void foreach(std::function<void(Key, const SkValue&)>) const;
 
+    // Array
+    size_t length() const;
+    const SkValue& at(size_t) const;
+    void append(SkValue);
+
+    template <typename T> static SkValue Encode(const T&);

[mtklein, 2016/01/20 14:20:59]

Let's make these

template <typename T>
SkValue SkToValue(const T&);

template <typename T>
bool SkFromValue(const SkValue&, T*);

It'll force us to stay honest to restrict these functions to use only SkValue's
public API.

Encode/Decode sound like we're doing something interesting, and I'd like these
functions to sound more mundane to reflect their (hopefully) mundane nature.  I
am not married on To/From.

[hal.canary, 2016/01/20 15:14:35]

done.

+    template <typename T> static bool Decode(const SkValue&, T*);
+
 private:
-    class Bytes;
-    class Object;
+    class Obj;
+    class Arr;
 
     Type fType;
     union {
-        int32_t       fS32;
-        uint32_t      fU32;
-        float         fF32;
-        class Bytes*  fBytes;
-        class Object* fObject;
+        int32_t  fS32;
+        uint32_t fU32;
+        float    fF32;
+        SkData*  fBytes;
+        Obj*     fObject;
+        Arr*     fArray;
     };
 };
 
-#endif//SkValue_DEFINED
+#endif  // SkValue_DEFINED