| PASS | Constructing a CSSSkewX with a keyword throws a TypeError | |
| PASS | Constructing a CSSSkewX with a double throws a TypeError | |
| PASS | Constructing a CSSSkewX with a unitless zero throws a TypeError | |
| PASS | Constructing a CSSSkewX with a string angle throws a TypeError | |
| PASS | Constructing a CSSSkewX with a number CSSUnitValue throws a TypeError | |
| PASS | Constructing a CSSSkewX with a time dimension CSSUnitValue throws a TypeError | |
| PASS | Constructing a CSSSkewX with a CSSMathValue of length type throws a TypeError | |
| PASS | Updating CSSSkewX.ax with a keyword throws a TypeError | |
| PASS | Updating CSSSkewX.ax with a double throws a TypeError | |
| PASS | Updating CSSSkewX.ax with a unitless zero throws a TypeError | |
| PASS | Updating CSSSkewX.ax with a string angle throws a TypeError | |
| PASS | Updating CSSSkewX.ax with a number CSSUnitValue throws a TypeError | |
| PASS | Updating CSSSkewX.ax with a time dimension CSSUnitValue throws a TypeError | |
| PASS | Updating CSSSkewX.ax with a CSSMathValue of length type throws a TypeError | |
| PASS | CSSSkewX can be constructed from an angle CSSUnitValue | |
| PASS | CSSSkewX can be constructed from a CSSMathValue of angle type | |
| PASS | CSSSkew.ax can be updated to an angle CSSUnitValue | |
| PASS | CSSSkew.ax can be updated to a CSSMathValue of angle type | |
| PASS | Modifying skewX.is2D is a no-op | |