From 30e381eea23624a2db5d43e0afe7f163dcf29cd0 Mon Sep 17 00:00:00 2001 From: wolfbeast Date: Fri, 13 Mar 2020 11:28:54 +0100 Subject: [PATCH] Issue #1485 - Fix incorrect grid cell sizing to min/max space. There were actually two separate logical errors in this method: The first part is that "origSizes.isSome()" is simply a bogus requirement for applying min/max-sizes here. I'm still keeping the optimization of not needlessly copying the mSizes array (as originally intended) since it's a quite common case. The second bug is that min/max-sizes were only applied under the "if (fr != 0.0f)" block. This is bogus since the calculated 'fr' value depends on 'aAvailableSize' which might change by applying min/max-sizes and thus 'fr' could become non-zero in the second round. To fix, this patch just moves "applyMinMax" block out one level. --- layout/generic/nsGridContainerFrame.cpp | 58 +++++++++---------- .../grid-max-sizing-flex-007-ref.html | 24 ++++++++ .../css-grid/grid-max-sizing-flex-007.html | 24 ++++++++ 3 files changed, 77 insertions(+), 29 deletions(-) diff --git a/layout/generic/nsGridContainerFrame.cpp b/layout/generic/nsGridContainerFrame.cpp index 959061e334..f771c9d7c5 100644 --- a/layout/generic/nsGridContainerFrame.cpp +++ b/layout/generic/nsGridContainerFrame.cpp @@ -4822,14 +4822,14 @@ nsGridContainerFrame::Tracks::StretchFlexibleTracks( : ri->ComputedMaxISize(); } Maybe> origSizes; + bool applyMinMax = (minSize != 0 || maxSize != NS_UNCONSTRAINEDSIZE) && + aAvailableSize == NS_UNCONSTRAINEDSIZE; // We iterate twice at most. The 2nd time if the grid size changed after // applying a min/max-size (can only occur if aAvailableSize is indefinite). while (true) { float fr = FindUsedFlexFraction(aState, aGridItems, flexTracks, aFunctions, aAvailableSize); if (fr != 0.0f) { - bool applyMinMax = (minSize != 0 || maxSize != NS_UNCONSTRAINEDSIZE) && - aAvailableSize == NS_UNCONSTRAINEDSIZE; for (uint32_t i : flexTracks) { float flexFactor = aFunctions.MaxSizingFor(i).GetFlexFractionValue(); nscoord flexLength = NSToCoordRound(flexFactor * fr); @@ -4841,36 +4841,36 @@ nsGridContainerFrame::Tracks::StretchFlexibleTracks( base = flexLength; } } - if (applyMinMax && origSizes.isSome()) { - // https://drafts.csswg.org/css-grid/#algo-flex-tracks - // "If using this flex fraction would cause the grid to be smaller than - // the grid container’s min-width/height (or larger than the grid - // container’s max-width/height), then redo this step, treating the free - // space as definite [...]" - nscoord newSize = 0; - for (auto& sz : mSizes) { - newSize += sz.mBase; - } - const auto sumOfGridGaps = SumOfGridGaps(); - newSize += sumOfGridGaps; - if (newSize > maxSize) { - aAvailableSize = maxSize; - } else if (newSize < minSize) { - aAvailableSize = minSize; - } - if (aAvailableSize != NS_UNCONSTRAINEDSIZE) { - // Reset min/max-size to ensure 'applyMinMax' becomes false next time. - minSize = 0; - maxSize = NS_UNCONSTRAINEDSIZE; - aAvailableSize = std::max(0, aAvailableSize - sumOfGridGaps); - // Restart with the original track sizes and definite aAvailableSize. + } + if (applyMinMax) { + applyMinMax = false; + // https://drafts.csswg.org/css-grid/#algo-flex-tracks + // "If using this flex fraction would cause the grid to be smaller than + // the grid container’s min-width/height (or larger than the grid + // container’s max-width/height), then redo this step, treating the free + // space as definite [...]" + nscoord newSize = 0; + for (auto& sz : mSizes) { + newSize += sz.mBase; + } + const auto sumOfGridGaps = SumOfGridGaps(); + newSize += sumOfGridGaps; + if (newSize > maxSize) { + aAvailableSize = maxSize; + } else if (newSize < minSize) { + aAvailableSize = minSize; + } + if (aAvailableSize != NS_UNCONSTRAINEDSIZE) { + aAvailableSize = std::max(0, aAvailableSize - sumOfGridGaps); + // Restart with the original track sizes and definite aAvailableSize. + if (origSizes.isSome()) { mSizes = Move(*origSizes); origSizes.reset(); - if (aAvailableSize == 0) { - break; // zero available size wouldn't change any sizes though... - } - continue; + } // else, no mSizes[].mBase were changed above so it's still correct + if (aAvailableSize == 0) { + break; // zero available size wouldn't change any sizes though... } + continue; } } break; diff --git a/layout/reftests/css-grid/grid-max-sizing-flex-007-ref.html b/layout/reftests/css-grid/grid-max-sizing-flex-007-ref.html index c5392d32cd..b17a1cc02e 100644 --- a/layout/reftests/css-grid/grid-max-sizing-flex-007-ref.html +++ b/layout/reftests/css-grid/grid-max-sizing-flex-007-ref.html @@ -107,4 +107,28 @@
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The first 6 grids should look the same:
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+ diff --git a/layout/reftests/css-grid/grid-max-sizing-flex-007.html b/layout/reftests/css-grid/grid-max-sizing-flex-007.html index ac9dcc77c4..a2f39e95be 100644 --- a/layout/reftests/css-grid/grid-max-sizing-flex-007.html +++ b/layout/reftests/css-grid/grid-max-sizing-flex-007.html @@ -105,4 +105,28 @@
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The first 6 grids should look the same:
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