Suppress warnings for step output property access (#236)

Fixes https://github.com/github/vscode-github-actions/issues/305

Step outputs are dynamic - actions can generate outputs based on
their inputs, so validating output property names is not feasible.

This marks step output dictionaries as incomplete so that accessing
any output property won't produce a warning. Known outputs from
action.yml will still be suggested for autocomplete.

languageservice/src/context-providers/steps.test.ts

@@ -0,0 +1,78 @@
+/* eslint-disable @typescript-eslint/no-non-null-assertion */
+import {DescriptionDictionary, isDescriptionDictionary} from "@actions/expressions";
+import {WorkflowContext} from "../context/workflow-context";
+import {getStepsContext} from "./steps";
+
+function createWorkflowContext(stepIds: string[], currentStepId?: string): WorkflowContext {
+  return {
+    job: {
+      steps: stepIds.map(id => ({id}))
+    },
+    step: currentStepId ? {id: currentStepId} : undefined
+  } as WorkflowContext;
+}
+
+describe("steps context", () => {
+  it("returns empty dictionary when no job", () => {
+    const workflowContext = {} as WorkflowContext;
+    const context = getStepsContext(workflowContext);
+    expect(context.pairs().length).toBe(0);
+  });
+
+  it("returns empty dictionary when no steps", () => {
+    const workflowContext = {job: {}} as WorkflowContext;
+    const context = getStepsContext(workflowContext);
+    expect(context.pairs().length).toBe(0);
+  });
+
+  it("includes steps with user-defined ids", () => {
+    const workflowContext = createWorkflowContext(["step-a", "step-b"]);
+    const context = getStepsContext(workflowContext);
+
+    expect(context.get("step-a")).toBeDefined();
+    expect(context.get("step-b")).toBeDefined();
+  });
+
+  it("excludes generated step ids (starting with __)", () => {
+    const workflowContext = createWorkflowContext(["step-a", "__generated"]);
+    const context = getStepsContext(workflowContext);
+
+    expect(context.get("step-a")).toBeDefined();
+    expect(context.get("__generated")).toBeUndefined();
+  });
+
+  it("excludes current step and later steps", () => {
+    const workflowContext = createWorkflowContext(["step-a", "step-b", "step-c"], "step-b");
+    const context = getStepsContext(workflowContext);
+
+    expect(context.get("step-a")).toBeDefined();
+    expect(context.get("step-b")).toBeUndefined();
+    expect(context.get("step-c")).toBeUndefined();
+  });
+
+  describe("step outputs", () => {
+    it("outputs is a dictionary, not null", () => {
+      const workflowContext = createWorkflowContext(["step-a"]);
+      const context = getStepsContext(workflowContext);
+
+      const stepContext = context.get("step-a");
+      expect(stepContext).toBeDefined();
+      expect(isDescriptionDictionary(stepContext!)).toBe(true);
+
+      const outputs = (stepContext as DescriptionDictionary).get("outputs");
+      expect(outputs).toBeDefined();
+      expect(isDescriptionDictionary(outputs!)).toBe(true);
+    });
+
+    it("outputs is marked incomplete to allow dynamic outputs", () => {
+      const workflowContext = createWorkflowContext(["step-a"]);
+      const context = getStepsContext(workflowContext);
+
+      const stepContext = context.get("step-a") as DescriptionDictionary;
+      const outputs = stepContext.get("outputs") as DescriptionDictionary;
+
+      // Outputs should be incomplete since we can't know what outputs a step will produce
+      expect(outputs.complete).toBe(false);
+    });
+  });
+});

languageservice/src/context-providers/steps.ts

@@ -31,7 +31,10 @@ function stepContext(): DescriptionDictionary {
   // https://docs.github.com/en/actions/learn-github-actions/contexts#steps-context
   const d = new DescriptionDictionary();
 
-  d.add("outputs", new data.Null(), getDescription("steps", "outputs"));
+  // Step outputs are dynamic - actions can generate outputs based on their inputs
+  const outputs = new DescriptionDictionary();
+  outputs.complete = false;
+  d.add("outputs", outputs, getDescription("steps", "outputs"));
 
   // Can be "success", "failure", "cancelled", or "skipped"
   d.add("conclusion", new data.Null(), getDescription("steps", "conclusion"));