Merge branch 'develop' into next

* develop: (50 commits)
  Use pixelmatch for image comparison
  Run all tests
  Fix lint
  Update lockfile
  E2E test
  Use cache to store snapshots
  chore(deps): update all patch dependencies
  Change string concatenation to template literal
  Revert "Revert 5041 feature/4935 subgraph title margin config option"
  build(deps-dev): bump follow-redirects from 1.15.2 to 1.15.5
  Run dev docs without npx
  Remove npx completely from run script
  Update docs
  Fix linters
  Removed volta requirement, leave pnpm only
  Fixed dead link
  build
  Update docs
  Updated contributing docs after review, minor fixes
  Updated gantt chart docs to show all config options
  ...

cypress/integration/other/configuration.spec.js

@@ -117,7 +117,6 @@ describe('Configuration', () => {
     });
     it('should not taint the initial configuration when using multiple directives', () => {
       const url = 'http://localhost:9000/regression/issue-1874.html';
-      cy.viewport(1440, 1024);
       cy.visit(url);
 
       cy.get('svg');

cypress/integration/other/rerender.spec.js

@@ -1,14 +1,12 @@
 describe('Rerendering', () => {
   it('should be able to render after an error has occurred', () => {
     const url = 'http://localhost:9000/render-after-error.html';
-    cy.viewport(1440, 1024);
     cy.visit(url);
     cy.get('#graphDiv').should('exist');
   });
 
   it('should be able to render and rerender a graph via API', () => {
     const url = 'http://localhost:9000/rerender.html';
-    cy.viewport(1440, 1024);
     cy.visit(url);
     cy.get('#graph [id^=flowchart-A]').should('have.text', 'XMas');
 

cypress/integration/rendering/flowchart-v2.spec.js

@@ -886,4 +886,93 @@ end
       });
     });
   });
+  describe('Subgraph title margins', () => {
+    it('Should render subgraphs with title margins set (LR)', () => {
+      imgSnapshotTest(
+        `flowchart LR
+
+          subgraph TOP
+              direction TB
+              subgraph B1
+                  direction RL
+                  i1 -->f1
+              end
+              subgraph B2
+                  direction BT
+                  i2 -->f2
+              end
+          end
+          A --> TOP --> B
+          B1 --> B2
+        `,
+        { flowchart: { subGraphTitleMargin: { top: 10, bottom: 5 } } }
+      );
+    });
+    it('Should render subgraphs with title margins set (TD)', () => {
+      imgSnapshotTest(
+        `flowchart TD
+
+          subgraph TOP
+              direction LR
+              subgraph B1
+                  direction RL
+                  i1 -->f1
+              end
+              subgraph B2
+                  direction BT
+                  i2 -->f2
+              end
+          end
+          A --> TOP --> B
+          B1 --> B2
+        `,
+        { flowchart: { subGraphTitleMargin: { top: 8, bottom: 16 } } }
+      );
+    });
+    it('Should render subgraphs with title margins set (LR) and htmlLabels set to false', () => {
+      imgSnapshotTest(
+        `flowchart LR
+
+          subgraph TOP
+              direction TB
+              subgraph B1
+                  direction RL
+                  i1 -->f1
+              end
+              subgraph B2
+                  direction BT
+                  i2 -->f2
+              end
+          end
+          A --> TOP --> B
+          B1 --> B2
+        `,
+        {
+          htmlLabels: false,
+          flowchart: { htmlLabels: false, subGraphTitleMargin: { top: 10, bottom: 5 } },
+        }
+      );
+    });
+    it('Should render subgraphs with title margins and edge labels', () => {
+      imgSnapshotTest(
+        `flowchart LR
+
+          subgraph TOP
+              direction TB
+              subgraph B1
+                  direction RL
+                  i1 --lb1-->f1
+              end
+              subgraph B2
+                  direction BT
+                  i2 --lb2-->f2
+              end
+          end
+          A --lb3--> TOP --lb4--> B
+          B1 --lb5--> B2
+        `,
+        { flowchart: { subGraphTitleMargin: { top: 10, bottom: 5 } } }
+      );
+    });
+  });
 });

cypress/integration/rendering/gantt.spec.js

@@ -245,7 +245,10 @@ describe('Gantt diagram', () => {
       const style = svg.attr('style');
       expect(style).to.match(/^max-width: [\d.]+px;$/);
       const maxWidthValue = parseFloat(style.match(/[\d.]+/g).join(''));
-      expect(maxWidthValue).to.be.within(984 * 0.95, 984 * 1.05);
+      expect(maxWidthValue).to.be.within(
+        Cypress.config().viewportWidth * 0.95,
+        Cypress.config().viewportWidth * 1.05
+      );
     });
   });
 
@@ -285,11 +288,11 @@ describe('Gantt diagram', () => {
       { gantt: { useMaxWidth: false } }
     );
     cy.get('svg').should((svg) => {
-      // const height = parseFloat(svg.attr('height'));
       const width = parseFloat(svg.attr('width'));
-      // use within because the absolute value can be slightly different depending on the environment ±5%
-      // expect(height).to.be.within(484 * 0.95, 484 * 1.05);
-      expect(width).to.be.within(984 * 0.95, 984 * 1.05);
+      expect(width).to.be.within(
+        Cypress.config().viewportWidth * 0.95,
+        Cypress.config().viewportWidth * 1.05
+      );
       expect(svg).to.not.have.attr('style');
     });
   });