Canvas: Handle switching between object and string based colors

When switching between the two it should respect whatever the color is
regardless of whether it is a color value or a string based color. This
also accounts for "invalid" colors as this should set the stroke-style
to be #000000 to be inline with the default stroke-style indicated in
the specification.

Change-Id: I00bee6c9a85787762271882838510b4187798ee0
Fixes: QTBUG-42155
Fixes: QTBUG-52959
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

1 files changed, 35 insertions, 0 deletions

diff --git a/tests/auto/quick/qquickcanvasitem/data/tst_strokeStyle.qml b/tests/auto/quick/qquickcanvasitem/data/tst_strokeStyle.qml
index 22803a19ce..a3f1ab0a9b 100644
--- a/tests/auto/quick/qquickcanvasitem/data/tst_strokeStyle.qml
+++ b/tests/auto/quick/qquickcanvasitem/data/tst_strokeStyle.qml
@@ -3,6 +3,8 @@ import QtQuick 2.0
 CanvasTestCase {
    id:testCase
    name: "strokeStyle"
+   property color anotherColor: "#0000ff"
+   property color emptyColor
    function init_data() { return testData("2d"); }
    function test_default(row) {
        var canvas = createCanvasObject(row);
@@ -46,4 +48,37 @@ CanvasTestCase {
        comparePixel(ctx,0,0,255,255,255,255);
        canvas.destroy()
    }
+   function test_colorFromObjectToString(row) {
+       var canvas = createCanvasObject(row);
+       var ctx = canvas.getContext('2d');
+
+       ctx.reset();
+       ctx.strokeStyle = anotherColor
+       ctx.strokeStyle = "red";
+       compare(ctx.strokeStyle, "#ff0000");
+
+       ctx.strokeStyle = anotherColor
+       ctx.strokeStyle = "black";
+       compare(ctx.strokeStyle, "#000000");
+
+       ctx.strokeStyle = "white";
+       ctx.strokeStyle = anotherColor
+       compare(ctx.strokeStyle, "#0000ff");
+       canvas.destroy()
+   }
+   function test_withInvalidColor(row) {
+       var canvas = createCanvasObject(row);
+       var ctx = canvas.getContext('2d');
+
+       ctx.reset();
+       ctx.strokeStyle = emptyColor
+       compare(ctx.strokeStyle, "#000000");
+       ctx.strokeStyle = "red";
+       compare(ctx.strokeStyle, "#ff0000");
+       ctx.strokeStyle = emptyColor
+       compare(ctx.strokeStyle, "#000000");
+       ctx.strokeStyle = anotherColor;
+       compare(ctx.strokeStyle, "#0000ff");
+       canvas.destroy()
+   }
 }