Change Chains margins behavior. Margins are now not part of the "spread" space.

They are still additive.

Test: added in ChainTest, plus added check163 in sherpa and updated checks in sherpa.

Fixes: 73521836, 74537416, 74130324

2 files changed, 53 insertions, 9 deletions

diff --git a/solver/src/main/java/android/support/constraint/solver/widgets/Chain.java b/solver/src/main/java/android/support/constraint/solver/widgets/Chain.java
index 777ae64..3ec6fca 100644
--- a/solver/src/main/java/android/support/constraint/solver/widgets/Chain.java
+++ b/solver/src/main/java/android/support/constraint/solver/widgets/Chain.java
@@ -317,13 +317,12 @@ class Chain {
                     SolverVariable beginNext = null;
                     SolverVariable beginNextTarget = null;
                     int beginMargin = beginAnchor.getMargin();
-                    int nextMargin = 0;
+                    int nextMargin = widget.mListAnchors[offset + 1].getMargin();
 
                     if (next != null) {
                         beginNextAnchor = next.mListAnchors[offset];
                         beginNext = beginNextAnchor.mSolverVariable;
                         beginNextTarget = beginNextAnchor.mTarget != null ? beginNextAnchor.mTarget.mSolverVariable : null;
-                        nextMargin = beginNextAnchor.getMargin();
                     } else {
                         beginNextAnchor = last.mListAnchors[offset + 1].mTarget;
                         if (beginNextAnchor != null) {
@@ -332,12 +331,18 @@ class Chain {
                         beginNextTarget = widget.mListAnchors[offset + 1].mSolverVariable;
                     }
 
+                    if (beginNextAnchor != null) {
+                        nextMargin += beginNextAnchor.getMargin();
+                    }
+                    if (previousVisibleWidget != null) {
+                        beginMargin += previousVisibleWidget.mListAnchors[offset + 1].getMargin();
+                    }
                     if (begin != null && beginTarget != null && beginNext != null && beginNextTarget != null) {
-                        int margin1 = 0;
+                        int margin1 = beginMargin;
                         if (widget == firstVisibleWidget) {
                             margin1 = firstVisibleWidget.mListAnchors[offset].getMargin();
                         }
-                        int margin2 = 0;
+                        int margin2 = nextMargin;
                         if (widget == lastVisibleWidget) {
                             margin2 = lastVisibleWidget.mListAnchors[offset + 1].getMargin();
                         }
@@ -355,7 +360,7 @@ class Chain {
             ConstraintWidget previousVisibleWidget = firstVisibleWidget;
             while (widget != null) {
                 next = widget.mListNextVisibleWidget[orientation];
-                if (widget != firstVisibleWidget && next != null) {
+                if (widget != firstVisibleWidget && widget != lastVisibleWidget && next != null) {
                     if (next == lastVisibleWidget) {
                         next = null;
                     }
@@ -367,13 +372,12 @@ class Chain {
                     SolverVariable beginNext = null;
                     SolverVariable beginNextTarget = null;
                     int beginMargin = beginAnchor.getMargin();
-                    int nextMargin = 0;
+                    int nextMargin = widget.mListAnchors[offset + 1].getMargin();
 
                     if (next != null) {
                         beginNextAnchor = next.mListAnchors[offset];
                         beginNext = beginNextAnchor.mSolverVariable;
                         beginNextTarget = beginNextAnchor.mTarget != null ? beginNextAnchor.mTarget.mSolverVariable : null;
-                        nextMargin = beginNextAnchor.getMargin();
                     } else {
                         beginNextAnchor = widget.mListAnchors[offset + 1].mTarget;
                         if (beginNextAnchor != null) {
@@ -382,9 +386,15 @@ class Chain {
                         beginNextTarget = widget.mListAnchors[offset + 1].mSolverVariable;
                     }
 
+                    if (beginNextAnchor != null) {
+                        nextMargin += beginNextAnchor.getMargin();
+                    }
+                    if (previousVisibleWidget != null) {
+                        beginMargin += previousVisibleWidget.mListAnchors[offset + 1].getMargin();
+                    }
                     if (begin != null && beginTarget != null && beginNext != null && beginNextTarget != null) {
-                        system.addCentering(begin, beginTarget, 0, 0.5f,
-                                beginNext, beginNextTarget, 0,
+                        system.addCentering(begin, beginTarget, beginMargin, 0.5f,
+                                beginNext, beginNextTarget, nextMargin,
                                 SolverVariable.STRENGTH_HIGHEST);
                     }
                 }
diff --git a/solver/src/test/java/android/support/constraint/solver/ChainTest.java b/solver/src/test/java/android/support/constraint/solver/ChainTest.java
index 53c7c90..8fc02d4 100644
--- a/solver/src/test/java/android/support/constraint/solver/ChainTest.java
+++ b/solver/src/test/java/android/support/constraint/solver/ChainTest.java
@@ -28,6 +28,40 @@ import static org.testng.Assert.assertEquals;
 public class ChainTest {
 
     @Test
+    public void testSpreadInsideChain2() {
+        ConstraintWidgetContainer root = new ConstraintWidgetContainer(0, 0, 600, 600);
+        ConstraintWidget A = new ConstraintWidget(100, 20);
+        ConstraintWidget B = new ConstraintWidget(100, 20);
+        ConstraintWidget C = new ConstraintWidget(100, 20);
+        root.setDebugName("root");
+        A.setDebugName("A");
+        B.setDebugName("B");
+        C.setDebugName("C");
+        root.add(A);
+        root.add(B);
+        root.add(C);
+
+        A.connect(ConstraintAnchor.Type.LEFT, root, ConstraintAnchor.Type.LEFT);
+        A.connect(ConstraintAnchor.Type.RIGHT, B, ConstraintAnchor.Type.LEFT);
+        B.connect(ConstraintAnchor.Type.LEFT, A, ConstraintAnchor.Type.RIGHT);
+        B.connect(ConstraintAnchor.Type.RIGHT, C, ConstraintAnchor.Type.LEFT);
+        C.connect(ConstraintAnchor.Type.LEFT, B, ConstraintAnchor.Type.RIGHT, 25);
+        C.connect(ConstraintAnchor.Type.RIGHT, root, ConstraintAnchor.Type.RIGHT);
+
+        A.setHorizontalChainStyle(ConstraintWidget.CHAIN_SPREAD_INSIDE);
+        B.setHorizontalDimensionBehaviour(ConstraintWidget.DimensionBehaviour.MATCH_CONSTRAINT);
+
+        root.layout();
+        System.out.println("A: " + A + " B: " + B + " C: " + C);
+        assertEquals(A.getLeft(), 0);
+        assertEquals(A.getRight(), 100);
+        assertEquals(B.getLeft(), 100);
+        assertEquals(B.getRight(), 475);
+        assertEquals(C.getLeft(), 500);
+        assertEquals(C.getRight(), 600);
+    }
+
+    @Test
     public void testPackChain() {
         ConstraintWidgetContainer root = new ConstraintWidgetContainer(0, 0, 600, 600);
         ConstraintWidget A = new ConstraintWidget(100, 20);