Draw a split table's background image on its later pages without warnings (#742)

CHANGELOG-GRAVITYPDF.md

@@ -271,6 +271,7 @@ Bugfixes
 * Styling a table row or row group, such as `tr.total { font-weight: bold }` or `<thead style="color: #fff">`, did not change the text of its cells, only their background. A `tr`, `thead`, `tbody` or `tfoot` now hands every inherited property to its cells, over the table's and under the cell's own, and a `tbody` rule reaches the rows written straight into a table. A row's `font-size: 80%` is taken of its row group's size, and a cell's of its row's. A row's `currentColor` is its row group's colour, and a cell's is its row's. A `th` stays bold, and is centred only when it inherits no `text-align` from its row, row group or table, as HTML's rendering rules have it. Under the standard `cssMode` only; set `'cssMode' => \Mpdf\CssMode::LEGACY` to keep the old output. [#542] [#655]
 * `text-outline-width` with no `text-outline-color` raised an undefined-key warning (`outline-COLOR`) and drew the outline black. The warning is gone in either `cssMode`. In standard mode the outline is now drawn in the colour of the text, as `text-outline-color` is `currentColor` by default, and `text-outline` with a width alone, such as `text-outline: 0.2mm`, which was ignored, outlines the text in its colour too. A text outline in `currentColor`, written or by default, is passed on as the keyword, so a `<span>` of another colour inside the outlined text is outlined in its own colour. Set `'cssMode' => \Mpdf\CssMode::LEGACY` to keep black outlines and to ignore that shorthand. [#552] [#650] [#681]
 * A percentage `border-radius` on a block, such as `border-radius: 50%` on a box 40 mm by 12 mm, drew a pill instead of an ellipse. Both radii were taken of the width of the block around it, and then shrunk to fit. A percentage is now of the block's own border box, as in CSS: a horizontal radius of its width and a vertical one of its height, so `50%` draws an ellipse and `10%` a corner a tenth of each side. A block split across pages resolves a vertical percentage against the height of the part on each page. With `autoPadding` on, a percentage radius no longer adds padding, since the box is not known when the padding is set. In both `cssMode`s. [#552] [#586]
+* A table split across pages raised `Undefined array key "gradient"` warnings on each later page when the table had a `background-image` from a URL. The image was drawn; the warnings are gone in either `cssMode`. [#552] [#742]
 
 ### Images and SVG
 
@@ -969,3 +970,4 @@ These changes do not change output.
 [#584]: https://github.com/GravityPDF/mpdf/issues/584
 [#689]: https://github.com/GravityPDF/mpdf/pull/689
 [#609]: https://github.com/GravityPDF/mpdf/issues/609
+[#742]: https://github.com/GravityPDF/mpdf/issues/742

src/Mpdf.php

@@ -23537,7 +23537,7 @@ function _tableWrite(&$table, $split = false, $startrow = 0, $startcol = 0, $spl
 										// The layers of a list are drawn in their order, so its gradients go in with its images
 										$gradientSlot = isset($table['background-image']['layers']) ? 2 : 1;
 										foreach ($this->backgroundLayers($table['background-image']) as $bg) {
-											if ($bg['gradient'] && preg_match('/(-moz-)*(repeating-)*(linear|radial)-gradient/', $bg['gradient'])) {
+											if (!empty($bg['gradient']) && preg_match('/(-moz-)*(repeating-)*(linear|radial)-gradient/', $bg['gradient'])) {
 												$g = $this->gradient->parseMozGradient($bg['gradient']);
 												if ($g) {
 													$this->tableBackgrounds[$level * 9 + $gradientSlot][] = ['gradient' => true, 'x' => $bx, 'y' => $by, 'w' => $bw, 'h' => $bh, 'gradtype' => $g['type'], 'stops' => $g['stops'], 'colorspace' => $g['colorspace'], 'coords' => $g['coords'], 'extend' => $g['extend'], 'clippath' => ''];

tests/Mpdf/TableBackgroundTest.php

@@ -5,6 +5,7 @@
 class TableBackgroundTest extends \Yoast\PHPUnitPolyfills\TestCases\TestCase
 {
 	use PageStreams;
+	use DrawnStyles;
 
 	const RED = '1.000 0.000 0.000 rg';
 
@@ -103,4 +104,29 @@ public function testATableWithNoBackgroundAfterAColouredOneIsStillUnaffected()
 		$this->assertCount(1, $this->redRectangles($this->render($html)));
 	}
 
+	/**
+	 * A table's background image from a URL has no gradient, and the background drawn again on each later page of a
+	 * table split across pages must not expect one: the image is tiled on every page and nothing is raised.
+	 *
+	 * @dataProvider modes
+	 *
+	 * @param string $cssMode
+	 */
+	public function testASplitTableWithABackgroundImageDrawsItOnEveryPageWithoutWarnings($cssMode)
+	{
+		$html = '<table style="background-image: url(' . $this->backgroundImage() . ')">'
+			. str_repeat('<tr><td>Row</td><td>Row</td></tr>', 80)
+			. '</table>';
+
+		$pdf = $this->assertDrawsSilently(function (Mpdf $mpdf) use ($html) {
+			$mpdf->WriteHTML($html);
+		}, ['cssMode' => $cssMode]);
+
+		$pages = $this->pageContents($pdf);
+		$this->assertGreaterThan(1, count($pages));
+		foreach ($pages as $page) {
+			$this->assertStringContainsString('/Pattern cs', $page);
+		}
+	}
+
 }