diff --git a/lib/tests-tree-builder/base.ts b/lib/tests-tree-builder/base.ts
index 1c4382ca4..d57fb408a 100644
--- a/lib/tests-tree-builder/base.ts
+++ b/lib/tests-tree-builder/base.ts
@@ -160,6 +160,17 @@ export class BaseTestsTreeBuilder {
                 const suite: TreeSuite = {id, parentId, name, suitePath, root: isRoot};
 
                 this._addSuite(suite);
+            } else if (suitePath.length > suites.byId[id].suitePath.length) {
+                const newParentId = this._buildId(suitePath.slice(0, -1));
+
+                suites.byId[id].parentId = newParentId;
+                suites.byId[id].suitePath = suitePath;
+                suites.byId[id].name = suites.byId[id].id.slice(newParentId.length + 1);
+
+                if (suites.byId[id].root) {
+                    suites.byId[id].root = false;
+                    suites.allRootIds.splice(suites.allRootIds.indexOf(id), 1);
+                }
             }
 
             if (ind !== arr.length - 1) {
diff --git a/test/unit/lib/tests-tree-builder/base.js b/test/unit/lib/tests-tree-builder/base.js
index 4805c5713..4faf6b4be 100644
--- a/test/unit/lib/tests-tree-builder/base.js
+++ b/test/unit/lib/tests-tree-builder/base.js
@@ -108,6 +108,88 @@ describe('ResultsTreeBuilder', () => {
                     }
                 );
             });
+
+            it('should transform root suite into non-root suite', () => {
+                builder.addTestResult(mkFormattedResult_({testPath: ['s1 s2', 's3']}));
+
+                assert.deepEqual(
+                    builder.tree.suites.byId['s1 s2'],
+                    {
+                        id: 's1 s2',
+                        name: 's1 s2',
+                        parentId: null,
+                        root: true,
+                        suitePath: ['s1 s2'],
+                        status: SUCCESS,
+                        suiteIds: ['s1 s2 s3']
+                    }
+                );
+
+                builder.addTestResult(mkFormattedResult_({testPath: ['s1', 's2', 's4']}));
+
+                assert.deepEqual(
+                    builder.tree.suites.byId['s1 s2'],
+                    {
+                        id: 's1 s2',
+                        name: 's2',
+                        parentId: 's1',
+                        root: false,
+                        suitePath: ['s1', 's2'],
+                        status: SUCCESS,
+                        suiteIds: ['s1 s2 s3', 's1 s2 s4']
+                    }
+                );
+            });
+
+            it('should transform suite into child suite', () => {
+                builder.addTestResult(mkFormattedResult_({testPath: ['s1', 's2 s3', 's4']}));
+
+                assert.deepEqual(
+                    builder.tree.suites.byId['s1 s2 s3'],
+                    {
+                        id: 's1 s2 s3',
+                        name: 's2 s3',
+                        parentId: 's1',
+                        root: false,
+                        suitePath: ['s1', 's2 s3'],
+                        status: SUCCESS,
+                        suiteIds: ['s1 s2 s3 s4']
+                    }
+                );
+
+                builder.addTestResult(mkFormattedResult_({testPath: ['s1', 's2', 's3', 's5']}));
+
+                assert.deepEqual(
+                    builder.tree.suites.byId['s1 s2 s3'],
+                    {
+                        id: 's1 s2 s3',
+                        name: 's3',
+                        parentId: 's1 s2',
+                        root: false,
+                        suitePath: ['s1', 's2', 's3'],
+                        status: SUCCESS,
+                        suiteIds: ['s1 s2 s3 s4', 's1 s2 s3 s5']
+                    }
+                );
+            });
+
+            it('should merge suite into existing one', () => {
+                builder.addTestResult(mkFormattedResult_({testPath: ['s1', 's2', 's3', 's4']}));
+                builder.addTestResult(mkFormattedResult_({testPath: ['s1', 's2 s3', 's5']}));
+
+                assert.deepEqual(
+                    builder.tree.suites.byId['s1 s2 s3'],
+                    {
+                        id: 's1 s2 s3',
+                        name: 's3',
+                        parentId: 's1 s2',
+                        root: false,
+                        suitePath: ['s1', 's2', 's3'],
+                        status: SUCCESS,
+                        suiteIds: ['s1 s2 s3 s4', 's1 s2 s3 s5']
+                    }
+                );
+            });
         });
 
         describe('"browsers" field in the tree', () => {