feat(workflow): Support defaults (#39)

* chore: Define Defaults type

* chore: Implement defaultsJSON

* feat(workflow): Support defaults

Author: koki-develop

lib/index.ts

@@ -1,5 +1,6 @@
 export * from "ghats/../.ghats/action.js";
 export * from "./package/concurrency";
+export * from "./package/defaults";
 export * from "./package/expression";
 export * from "./package/job";
 export * from "./package/on";

lib/internal/defaults.spec.ts

@@ -0,0 +1,21 @@
+import { describe, expect, test } from "bun:test";
+import type { Defaults } from "../package/defaults";
+import { defaultsJSON } from "./defaults";
+
+describe("defaultsJSON", () => {
+  test.each<[Defaults, ReturnType<typeof defaultsJSON>]>([
+    [{}, {}],
+    [{ run: {} }, { run: {} }],
+    [{ run: { shell: "bash" } }, { run: { shell: "bash" } }],
+    [
+      { run: { workingDirectory: "src" } },
+      { run: { "working-directory": "src" } },
+    ],
+    [
+      { run: { shell: "bash", workingDirectory: "src" } },
+      { run: { shell: "bash", "working-directory": "src" } },
+    ],
+  ])("defaultsJSON(%j) -> %j", (defaults, expected) => {
+    expect(defaultsJSON(defaults)).toEqual(expected);
+  });
+});

lib/internal/defaults.ts

@@ -0,0 +1,16 @@
+import type { Defaults } from "../package/defaults";
+
+export function defaultsJSON(defaults: Defaults): Record<string, unknown> {
+  return {
+    ...(defaults.run != null && {
+      run: {
+        ...(defaults.run.shell != null && {
+          shell: defaults.run.shell,
+        }),
+        ...(defaults.run.workingDirectory != null && {
+          "working-directory": defaults.run.workingDirectory,
+        }),
+      },
+    }),
+  };
+}

lib/package/defaults.ts

@@ -0,0 +1,8 @@
+import type { Shell } from "./shell";
+
+export type Defaults = {
+  run?: {
+    shell?: Shell;
+    workingDirectory?: string;
+  };
+};

lib/package/workflow.spec.ts

@@ -9,22 +9,33 @@ describe("Workflow", () => {
       { name: "simple", on: "push", jobs: {} },
     ],
     [
-      new Workflow("simple", { runName: "Simple Workflow", on: "push" }),
-      { name: "simple", "run-name": "Simple Workflow", on: "push", jobs: {} },
+      new Workflow("with run-name", { runName: "Simple Workflow", on: "push" }),
+      {
+        name: "with run-name",
+        "run-name": "Simple Workflow",
+        on: "push",
+        jobs: {},
+      },
     ],
     [
-      new Workflow("simple", { on: "push", permissions: { contents: "read" } }),
+      new Workflow("with permissions", {
+        on: "push",
+        permissions: { contents: "read" },
+      }),
       {
-        name: "simple",
+        name: "with permissions",
         on: "push",
         permissions: { contents: "read" },
         jobs: {},
       },
     ],
     [
-      new Workflow("simple", { on: "push", env: { FOO: "foo", BAR: "bar" } }),
+      new Workflow("with env", {
+        on: "push",
+        env: { FOO: "foo", BAR: "bar" },
+      }),
       {
-        name: "simple",
+        name: "with env",
         on: "push",
         env: {
           FOO: "foo",
@@ -34,12 +45,12 @@ describe("Workflow", () => {
       },
     ],
     [
-      new Workflow("simple", {
+      new Workflow("with concurrency", {
         on: "push",
         concurrency: { group: "group", cancelInProgress: true },
       }),
       {
-        name: "simple",
+        name: "with concurrency",
         on: "push",
         concurrency: {
           group: "group",
@@ -48,21 +59,33 @@ describe("Workflow", () => {
         jobs: {},
       },
     ],
+    [
+      new Workflow("with defaults", {
+        on: "push",
+        defaults: { run: { shell: "bash" } },
+      }),
+      {
+        name: "with defaults",
+        on: "push",
+        defaults: { run: { shell: "bash" } },
+        jobs: {},
+      },
+    ],
     [
       (() => {
-        const workflow = new Workflow("simple", { on: "push" });
+        const workflow = new Workflow("with job", { on: "push" });
         workflow.addJob(
-          new Job("test", {
+          new Job("simple-job", {
             runsOn: "ubuntu-latest",
           }).run("echo 'Hello, world!'"),
         );
         return workflow;
       })(),
       {
-        name: "simple",
+        name: "with job",
         on: "push",
         jobs: {
-          test: {
+          "simple-job": {
             "runs-on": "ubuntu-latest",
             steps: [{ run: "echo 'Hello, world!'" }],
           },

lib/package/workflow.ts

@@ -1,8 +1,10 @@
 import { concurrencyJSON } from "../internal/concurrency";
+import { defaultsJSON } from "../internal/defaults";
 import { envJSON } from "../internal/env";
 import { onJSON } from "../internal/on";
 import { permissionsJSON } from "../internal/permissions";
 import { type Concurrency } from "./concurrency";
+import type { Defaults } from "./defaults";
 import { type Env } from "./env";
 import { Job } from "./job";
 import { type On } from "./on";
@@ -14,7 +16,7 @@ export type WorkflowConfig = {
   on: On;
   permissions?: Permissions;
   env?: Env;
-  // TODO: defaults
+  defaults?: Defaults;
 };
 
 export class Workflow {
@@ -50,6 +52,10 @@ export class Workflow {
         concurrency: concurrencyJSON(this._config.concurrency),
       }),
 
+      ...(this._config.defaults && {
+        defaults: defaultsJSON(this._config.defaults),
+      }),
+
       jobs: this._jobs.reduce<Record<string, unknown>>((acc, job) => {
         acc[job.id] = job.toJSON();
         return acc;