Consider min and max container's heights while processing line's cross size

DEVSIX-5178

Autoported commit.
Original commit hash: [ff71d20b0]

Author: ars18wrw

itext.tests/itext.layout.tests/itext/layout/element/FlexContainerTest.cs

@@ -720,6 +720,55 @@ public virtual void RespectFlexContainersWidthTest() {
                 , "diff"));
         }
 
+        [NUnit.Framework.Test]
+        public virtual void FlexItemsMinHeightShouldBeOverriddenTest() {
+            String outFileName = destinationFolder + "flexItemsMinHeightShouldBeOverriddenTest" + testNumber + ".pdf";
+            String cmpFileName = sourceFolder + "cmp_flexItemsMinHeightShouldBeOverriddenTest" + testNumber + ".pdf";
+            PdfDocument pdfDocument = new PdfDocument(new PdfWriter(outFileName));
+            Document document = new Document(pdfDocument);
+            Div flexContainer = CreateFlexContainer();
+            flexContainer.Add(new Div().SetWidth(100).SetBackgroundColor(ColorConstants.BLUE).SetHeight(100));
+            flexContainer.Add(new Div().SetWidth(100).SetBackgroundColor(ColorConstants.YELLOW).SetMinHeight(20));
+            document.Add(flexContainer);
+            document.Close();
+            NUnit.Framework.Assert.IsNull(new CompareTool().CompareByContent(outFileName, cmpFileName, destinationFolder
+                , "diff"));
+        }
+
+        [NUnit.Framework.Test]
+        public virtual void LinesMinHeightShouldBeRespectedTest() {
+            String outFileName = destinationFolder + "linesMinHeightShouldBeRespectedTest" + testNumber + ".pdf";
+            String cmpFileName = sourceFolder + "cmp_linesMinHeightShouldBeRespectedTest" + testNumber + ".pdf";
+            PdfDocument pdfDocument = new PdfDocument(new PdfWriter(outFileName));
+            Document document = new Document(pdfDocument);
+            Div flexContainer = CreateFlexContainer();
+            flexContainer.SetMinHeight(100);
+            Div child = new Div().SetWidth(100).SetBackgroundColor(ColorConstants.BLUE);
+            child.Add(new Paragraph().SetWidth(100).SetBackgroundColor(ColorConstants.YELLOW));
+            flexContainer.Add(child);
+            document.Add(flexContainer);
+            document.Close();
+            NUnit.Framework.Assert.IsNull(new CompareTool().CompareByContent(outFileName, cmpFileName, destinationFolder
+                , "diff"));
+        }
+
+        [NUnit.Framework.Test]
+        public virtual void LinesMaxHeightShouldBeRespectedTest() {
+            String outFileName = destinationFolder + "linesMaxHeightShouldBeRespectedTest" + testNumber + ".pdf";
+            String cmpFileName = sourceFolder + "cmp_linesMaxHeightShouldBeRespectedTest" + testNumber + ".pdf";
+            PdfDocument pdfDocument = new PdfDocument(new PdfWriter(outFileName));
+            Document document = new Document(pdfDocument);
+            Div flexContainer = CreateFlexContainer();
+            flexContainer.SetMaxHeight(100);
+            Div child = new Div().SetWidth(100).SetBackgroundColor(ColorConstants.BLUE).SetHeight(150);
+            child.Add(new Paragraph().SetWidth(100).SetBackgroundColor(ColorConstants.YELLOW));
+            flexContainer.Add(child);
+            document.Add(flexContainer);
+            document.Close();
+            NUnit.Framework.Assert.IsNull(new CompareTool().CompareByContent(outFileName, cmpFileName, destinationFolder
+                , "diff"));
+        }
+
         private Div GetFlexContainer(OverflowPropertyValue? overflowX, Style style) {
             FlexContainer flexContainer = CreateFlexContainer();
             flexContainer.SetBackgroundColor(ColorConstants.GREEN).SetBorderRight(new SolidBorder(60));

itext.tests/itext.layout.tests/resources/itext/layout/FlexContainerTest/cmp_linesMaxHeightShouldBeRespectedTest1.pdf

@@ -87,8 +87,9 @@ public static IList<IList<FlexItemInfo>> CalculateChildrenRectangles(Rectangle f
                 mainSize = layoutBox.GetWidth();
             }
             // We need to have crossSize only if its value is definite.
-            // The calculation differs from width calculation because if width isn't definite, parent's width shall be taken
-            float? crossSize = flexContainerRenderer.RetrieveMinHeight();
+            float? crossSize = flexContainerRenderer.RetrieveHeight();
+            float? minCrossSize = flexContainerRenderer.RetrieveMinHeight();
+            float? maxCrossSize = flexContainerRenderer.RetrieveMaxHeight();
             DetermineFlexBasisAndHypotheticalMainSizeForFlexItems(flexItemCalculationInfos, (float)mainSize);
             // 9.3. Main Size Determination
             // 5. Collect flex items into flex lines:
@@ -105,7 +106,8 @@ public static IList<IList<FlexItemInfo>> CalculateChildrenRectangles(Rectangle f
             // performing layout with the used main size and the available space, treating auto as fit-content.
             DetermineHypotheticalCrossSizeForFlexItems(lines);
             // 8. Calculate the cross size of each flex line.
-            IList<float> lineCrossSizes = CalculateCrossSizeOfEachFlexLine(lines, isSingleLine, crossSize);
+            IList<float> lineCrossSizes = CalculateCrossSizeOfEachFlexLine(lines, isSingleLine, minCrossSize, crossSize
+                , maxCrossSize);
             // TODO DEVSIX-5003 min/max height calculations are not supported
             // If the flex container is single-line, then clamp the line’s cross-size to be within
             // the container’s computed min and max cross sizes. Note that if CSS 2.1’s definition of min/max-width/height
@@ -353,7 +355,7 @@ internal static void DetermineHypotheticalCrossSizeForFlexItems(IList<IList<Flex
         }
 
         internal static IList<float> CalculateCrossSizeOfEachFlexLine(IList<IList<FlexUtil.FlexItemCalculationInfo
-            >> lines, bool isSingleLine, float? crossSize) {
+            >> lines, bool isSingleLine, float? minCrossSize, float? crossSize, float? maxCrossSize) {
             IList<float> lineCrossSizes = new List<float>();
             if (isSingleLine && crossSize != null && !lines.IsEmpty()) {
                 lineCrossSizes.Add((float)crossSize);
@@ -378,6 +380,16 @@ internal static IList<float> CalculateCrossSizeOfEachFlexLine(IList<IList<FlexUt
                         }
                         flexLinesCrossSize = Math.Max(0, largestHypotheticalCrossSize);
                     }
+                    // 3. If the flex container is single-line, then clamp the line’s cross-size to be
+                    // within the container’s computed min and max cross sizes
+                    if (isSingleLine && !lines.IsEmpty()) {
+                        if (null != minCrossSize) {
+                            flexLinesCrossSize = Math.Max((float)minCrossSize, flexLinesCrossSize);
+                        }
+                        if (null != maxCrossSize) {
+                            flexLinesCrossSize = Math.Min((float)maxCrossSize, flexLinesCrossSize);
+                        }
+                    }
                     lineCrossSizes.Add(flexLinesCrossSize);
                 }
             }