Extend and improve propTypes. Optimize javascript hidden classes and inline caching in V8.

Add lengthAdjust and textLength text / tspan attributes.

lib/props.js

@@ -48,6 +48,16 @@ const strokeProps = {
     strokeMiterlimit: numberProp
 };
 
+const pathProps = {
+    ...fillProps,
+    ...strokeProps,
+    ...clipProps,
+    ...transformProps,
+    ...responderProps,
+    ...touchableProps,
+    ...definationProps
+};
+
 // normal | italic | oblique | inherit
 // https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/font-style
 const fontStyle = PropTypes.oneOf(['normal', 'italic', 'oblique']);
@@ -127,6 +137,102 @@ const fontProps = {
     font
 };
 
+/*
+ Name	Value	Initial value	Animatable
+ lengthAdjust	spacing | spacingAndGlyphs	spacing	yes
+ https://svgwg.org/svg2-draft/text.html#TextElementLengthAdjustAttribute
+ https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/lengthAdjust
+ */
+const lengthAdjust = PropTypes.oneOf(['spacing', 'spacingAndGlyphs']);
+
+/*
+ Name	Value	Initial value	Animatable
+ textLength	<length> | <percentage> | <number>	See below	yes
+ https://svgwg.org/svg2-draft/text.html#TextElementTextLengthAttribute
+ https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/textLength
+*/
+const textLength = PropTypes.string;
+
+const textSpecificProps = {
+    ...pathProps,
+    ...fontProps,
+    lengthAdjust,
+    textLength,
+}
+
+// https://svgwg.org/svg2-draft/text.html#TSpanAttributes
+const textProps = {
+    ...textSpecificProps,
+    dx: PropTypes.string,
+    dy: PropTypes.string,
+}
+
+/*
+ Name
+ side
+ Value
+ left | right
+ initial value
+ left
+ Animatable
+ yes
+ https://svgwg.org/svg2-draft/text.html#TextPathElementSideAttribute
+*/
+const side = PropTypes.oneOf(['left', 'right']);
+
+/*
+ Name
+ startOffset
+ Value
+ <length> | <percentage> | <number>
+ initial value
+ 0
+ Animatable
+ yes
+ https://svgwg.org/svg2-draft/text.html#TextPathElementStartOffsetAttribute
+ https://developer.mozilla.org/en/docs/Web/SVG/Element/textPath
+ */
+const startOffset = PropTypes.string;
+
+/*
+ Name
+ method
+ Value
+ align | stretch
+ initial value
+ align
+ Animatable
+ yes
+ https://svgwg.org/svg2-draft/text.html#TextPathElementMethodAttribute
+ https://developer.mozilla.org/en/docs/Web/SVG/Element/textPath
+ */
+const method = PropTypes.oneOf(['align', 'stretch']);
+
+/*
+ Name
+ spacing
+ Value
+ auto | exact
+ initial value
+ exact
+ Animatable
+ yes
+ https://svgwg.org/svg2-draft/text.html#TextPathElementSpacingAttribute
+ https://developer.mozilla.org/en/docs/Web/SVG/Element/textPath
+ */
+const spacing = PropTypes.oneOf(['auto', 'exact']);
+
+// https://svgwg.org/svg2-draft/text.html#TextPathAttributes
+// https://developer.mozilla.org/en/docs/Web/SVG/Element/textPath
+const textPathProps = {
+    ...textSpecificProps,
+    href: PropTypes.string.isRequired,
+    startOffset,
+    method,
+    spacing,
+    side,
+}
+
 const transformProps = {
     scale: numberProp,
     scaleX: numberProp,
@@ -147,21 +253,13 @@ const transformProps = {
     transform: PropTypes.oneOfType([PropTypes.object, PropTypes.string])
 };
 
-const pathProps = {
-    ...fillProps,
-    ...strokeProps,
-    ...clipProps,
-    ...transformProps,
-    ...responderProps,
-    ...touchableProps,
-    ...definationProps
-};
-
 export {
     numberProp,
     fillProps,
     strokeProps,
     fontProps,
+    textProps,
+    textPathProps,
     clipProps,
     pathProps,
     responderProps,