Make sure that we render a max of 3 arrow lanes.

unexpectedjs · Sep 15, 2016 · 56adf78 · 56adf78
1 parent 5898673
commit 56adf78
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Showing 5 changed files with 34 additions and 3 deletions.
diff --git a/lib/assertions.js b/lib/assertions.js
@@ -1044,7 +1044,7 @@ module.exports = function (expect) {
                             if (subjectType.indent) {
                                 output.indentLines();
                             }
-                            var packing = utils.packArrows(changes);
+                            var packing = utils.packArrows(changes); // NOTE: Will have side effects in changes if the packing results in too many arrow lanes
                             output.arrowsAlongsideChangeOutputs(packing, changes.map(function (diffItem, index) {
                                 var delimiterOutput = subjectType.delimiter(output.clone(), index, indexOfLastNonInsert + 1);
                                 return output.clone().block(function () {

diff --git a/lib/styles.js b/lib/styles.js
@@ -451,6 +451,7 @@ module.exports = function (expect) {
         } else {
             this.i();
         }
+
         this.block(function () {
             changeOutputs.forEach(function (changeOutput, index) {
                 this.nl(index > 0 ? 1 : 0).i().append(changeOutput);

diff --git a/lib/types.js b/lib/types.js
@@ -557,7 +557,8 @@ module.exports = function (expect) {
             var indexOfLastNonInsert = changes.reduce(function (previousValue, diffItem, index) {
                 return (diffItem.type === 'insert') ? previousValue : index;
             }, -1);
-            output.arrowsAlongsideChangeOutputs(utils.packArrows(changes), changes.map(function (diffItem, index) {
+            var packing = utils.packArrows(changes); // NOTE: Will have side effects in changes if the packing results in too many arrow lanes
+            output.arrowsAlongsideChangeOutputs(packing, changes.map(function (diffItem, index) {
                 var delimiterOutput = type.delimiter(output.clone(), index, indexOfLastNonInsert + 1);
                 return output.clone().block(function () {
                     var type = diffItem.type;

diff --git a/lib/utils.js b/lib/utils.js
@@ -179,7 +179,15 @@ var utils = module.exports = {
                 });
             });
 
-            return greedyIntervalPacker(arrowSpecs);
+            var packing = greedyIntervalPacker(arrowSpecs);
+            while (packing.length > 3) {
+                // The arrow packing takes up too many lanes. Turn the moveSource/moveTarget items into inserts and removes
+                packing.shift().forEach(function (entry) {
+                    changes[entry.direction === 'up' ? entry.start : entry.end].type = 'insert';
+                    changes[entry.direction === 'up' ? entry.end : entry.start].type = 'remove';
+                });
+            }
+            return packing;
         }
     }
 };
diff --git a/test/types/array-like-type.spec.js b/test/types/array-like-type.spec.js
@@ -206,6 +206,27 @@ describe('array-like type', function () {
         );
     });
 
+    it('should stop rendering more arrows when there would be more than 3 lanes', function () {
+        expect(function () {
+            expect(['a', 'b', 'c', 'd', 'e', 'f'], 'to equal', ['f', 'c', 'd', 'e', 'a', 'b']);
+        }, 'to error with',
+            "expected [ 'a', 'b', 'c', 'd', 'e', 'f' ] to equal [ 'f', 'c', 'd', 'e', 'a', 'b' ]\n" +
+            "\n" +
+            "[\n" +
+            "        // missing 'f'\n" +
+            "┌─────▷\n" +
+            "│ ┌───▷\n" +
+            "│ │ ┌─▷\n" +
+            "│ │ │   'a',\n" +
+            "│ │ │   'b',\n" +
+            "└─│─│── 'c', // should be moved\n" +
+            "  └─│── 'd', // should be moved\n" +
+            "    └── 'e', // should be moved\n" +
+            "        'f' // should be removed\n" +
+            "]"
+        );
+    });
+
     it('should render multiple moved items with arrows', function () {
         expect(function () {
             expect(['a', 'b', 'c', 'd'], 'to equal', ['d', 'b', 'a', 'c']);