handle step.if: false

Signed-off-by: Matt Benson <gudnabrsam@gmail.com>

.changeset/curly-tomatoes-reply.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-scaffolder-backend': patch
+---
+
+handle step.if: false

plugins/scaffolder-backend/src/scaffolder/tasks/NunjucksWorkflowRunner.test.ts

@@ -407,6 +407,48 @@ describe('NunjucksWorkflowRunner', () => {
 
       expect(output.result).toBeUndefined();
     });
+    describe('should apply boolean step conditions', () => {
+      it('executes when true', async () => {
+        const task = createMockTaskWithSpec({
+          apiVersion: 'scaffolder.backstage.io/v1beta3',
+          steps: [
+            {
+              id: 'conditional',
+              name: 'conditional',
+              action: 'output-action',
+              if: true,
+            },
+          ],
+          output: {
+            result: '${{ steps.conditional.output.mock }}',
+          },
+          parameters: {},
+        });
+
+        const { output } = await runner.execute(task);
+        expect(output.result).toBe('backstage');
+      });
+      it('skips when false', async () => {
+        const task = createMockTaskWithSpec({
+          apiVersion: 'scaffolder.backstage.io/v1beta3',
+          steps: [
+            {
+              id: 'conditional',
+              name: 'conditional',
+              action: 'output-action',
+              if: false,
+            },
+          ],
+          output: {
+            result: '${{ steps.conditional.output.mock }}',
+          },
+          parameters: {},
+        });
+
+        const { output } = await runner.execute(task);
+        expect(output.result).toBeUndefined();
+      });
+    });
   });
 
   describe('templating', () => {

plugins/scaffolder-backend/src/scaffolder/tasks/NunjucksWorkflowRunner.ts

@@ -244,14 +244,14 @@ export class NunjucksWorkflowRunner implements WorkflowRunner {
     }
 
     try {
-      if (step.if) {
-        const ifResult = this.render(step.if, context, renderTemplate);
-        if (!isTruthy(ifResult)) {
-          await stepTrack.skipFalsy();
-          return;
-        }
+      if (
+        step.if === false ||
+        (typeof step.if === 'string' &&
+          !isTruthy(this.render(step.if, context, renderTemplate)))
+      ) {
+        await stepTrack.skipFalsy();
+        return;
       }
-
       const action: TemplateAction<JsonObject> =
         this.options.actionRegistry.get(step.action);
       const { taskLogger, streamLogger } = createStepLogger({