Add label trigger functionality to Claude Code Action (#177)

- introduced a new input parameter `label_trigger` in `action.yml` to allow triggering actions based on specific labels applied to issues.
- Enhanced the context preparation and event handling in the code to support the new labled event.

test/create-prompt.test.ts

@@ -226,6 +226,33 @@ describe("generatePrompt", () => {
     );
   });
 
+  test("should generate prompt for issue labeled event", () => {
+    const envVars: PreparedContext = {
+      repository: "owner/repo",
+      claudeCommentId: "12345",
+      triggerPhrase: "@claude",
+      eventData: {
+        eventName: "issues",
+        eventAction: "labeled",
+        isPR: false,
+        issueNumber: "888",
+        baseBranch: "main",
+        claudeBranch: "claude/issue-888-20240101_120000",
+        labelTrigger: "claude-task",
+      },
+    };
+
+    const prompt = generatePrompt(envVars, mockGitHubData);
+
+    expect(prompt).toContain("<event_type>ISSUE_LABELED</event_type>");
+    expect(prompt).toContain(
+      "<trigger_context>issue labeled with 'claude-task'</trigger_context>",
+    );
+    expect(prompt).toContain(
+      "[Create a PR](https://github.com/owner/repo/compare/main",
+    );
+  });
+
   test("should include direct prompt when provided", () => {
     const envVars: PreparedContext = {
       repository: "owner/repo",
@@ -615,6 +642,28 @@ describe("getEventTypeAndContext", () => {
     expect(result.triggerContext).toBe("issue assigned to 'claude-bot'");
   });
 
+  test("should return correct type and context for issue labeled", () => {
+    const envVars: PreparedContext = {
+      repository: "owner/repo",
+      claudeCommentId: "12345",
+      triggerPhrase: "@claude",
+      eventData: {
+        eventName: "issues",
+        eventAction: "labeled",
+        isPR: false,
+        issueNumber: "888",
+        baseBranch: "main",
+        claudeBranch: "claude/issue-888-20240101_120000",
+        labelTrigger: "claude-task",
+      },
+    };
+
+    const result = getEventTypeAndContext(envVars);
+
+    expect(result.eventType).toBe("ISSUE_LABELED");
+    expect(result.triggerContext).toBe("issue labeled with 'claude-task'");
+  });
+
   test("should return correct type and context for issue assigned without assigneeTrigger", () => {
     const envVars: PreparedContext = {
       repository: "owner/repo",

test/mockContext.ts

@@ -10,6 +10,7 @@ import type {
 const defaultInputs = {
   triggerPhrase: "/claude",
   assigneeTrigger: "",
+  labelTrigger: "",
   anthropicModel: "claude-3-7-sonnet-20250219",
   allowedTools: [] as string[],
   disallowedTools: [] as string[],
@@ -128,6 +129,46 @@ export const mockIssueAssignedContext: ParsedGitHubContext = {
   inputs: { ...defaultInputs, assigneeTrigger: "@claude-bot" },
 };
 
+export const mockIssueLabeledContext: ParsedGitHubContext = {
+  runId: "1234567890",
+  eventName: "issues",
+  eventAction: "labeled",
+  repository: defaultRepository,
+  actor: "admin-user",
+  payload: {
+    action: "labeled",
+    issue: {
+      number: 1234,
+      title: "Enhancement: Improve search functionality",
+      body: "The current search is too slow and needs optimization",
+      user: {
+        login: "alice-wonder",
+        id: 54321,
+        avatar_url: "https://avatars.githubusercontent.com/u/54321",
+        html_url: "https://github.com/alice-wonder",
+      },
+      assignee: null,
+    },
+    label: {
+      id: 987654321,
+      name: "claude-task",
+      color: "f29513",
+      description: "Label for Claude AI interactions",
+    },
+    repository: {
+      name: "test-repo",
+      full_name: "test-owner/test-repo",
+      private: false,
+      owner: {
+        login: "test-owner",
+      },
+    },
+  } as IssuesEvent,
+  entityNumber: 1234,
+  isPR: false,
+  inputs: { ...defaultInputs, labelTrigger: "claude-task" },
+};
+
 // Issue comment on issue event
 export const mockIssueCommentContext: ParsedGitHubContext = {
   runId: "1234567890",

test/permissions.test.ts

@@ -62,6 +62,7 @@ describe("checkWritePermissions", () => {
     inputs: {
       triggerPhrase: "@claude",
       assigneeTrigger: "",
+      labelTrigger: "",
       allowedTools: [],
       disallowedTools: [],
       customInstructions: "",

test/trigger-validation.test.ts

@@ -6,6 +6,7 @@ import { describe, it, expect } from "bun:test";
 import {
   createMockContext,
   mockIssueAssignedContext,
+  mockIssueLabeledContext,
   mockIssueCommentContext,
   mockIssueOpenedContext,
   mockPullRequestReviewContext,
@@ -29,6 +30,7 @@ describe("checkContainsTrigger", () => {
         inputs: {
           triggerPhrase: "/claude",
           assigneeTrigger: "",
+          labelTrigger: "",
           directPrompt: "Fix the bug in the login form",
           allowedTools: [],
           disallowedTools: [],
@@ -55,6 +57,7 @@ describe("checkContainsTrigger", () => {
         inputs: {
           triggerPhrase: "/claude",
           assigneeTrigger: "",
+          labelTrigger: "",
           directPrompt: "",
           allowedTools: [],
           disallowedTools: [],
@@ -107,6 +110,39 @@ describe("checkContainsTrigger", () => {
     });
   });
 
+  describe("label trigger", () => {
+    it("should return true when issue is labeled with the trigger label", () => {
+      const context = mockIssueLabeledContext;
+      expect(checkContainsTrigger(context)).toBe(true);
+    });
+
+    it("should return false when issue is labeled with a different label", () => {
+      const context = {
+        ...mockIssueLabeledContext,
+        payload: {
+          ...mockIssueLabeledContext.payload,
+          label: {
+            ...(mockIssueLabeledContext.payload as any).label,
+            name: "bug",
+          },
+        },
+      } as ParsedGitHubContext;
+      expect(checkContainsTrigger(context)).toBe(false);
+    });
+
+    it("should return false for non-labeled events", () => {
+      const context = {
+        ...mockIssueLabeledContext,
+        eventAction: "opened",
+        payload: {
+          ...mockIssueLabeledContext.payload,
+          action: "opened",
+        },
+      } as ParsedGitHubContext;
+      expect(checkContainsTrigger(context)).toBe(false);
+    });
+  });
+
   describe("issue body and title trigger", () => {
     it("should return true when issue body contains trigger phrase", () => {
       const context = mockIssueOpenedContext;
@@ -232,6 +268,7 @@ describe("checkContainsTrigger", () => {
         inputs: {
           triggerPhrase: "@claude",
           assigneeTrigger: "",
+          labelTrigger: "",
           directPrompt: "",
           allowedTools: [],
           disallowedTools: [],
@@ -259,6 +296,7 @@ describe("checkContainsTrigger", () => {
         inputs: {
           triggerPhrase: "@claude",
           assigneeTrigger: "",
+          labelTrigger: "",
           directPrompt: "",
           allowedTools: [],
           disallowedTools: [],
@@ -286,6 +324,7 @@ describe("checkContainsTrigger", () => {
         inputs: {
           triggerPhrase: "@claude",
           assigneeTrigger: "",
+          labelTrigger: "",
           directPrompt: "",
           allowedTools: [],
           disallowedTools: [],