feature: print helm-docs diff when fail-on-diff is true

Signed-off-by: Aleksandar Stojanov <[email protected]>

.github/workflows/ci.yaml

@@ -62,10 +62,12 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Test Local Action
+        continue-on-error: true
         id: test-action
         uses: ./
         with:
           chart-search-root: __tests__/fixtures
+          fail-on-diff: true
 
       - name: Print Output
         id: output

__tests__/fixtures/Chart.yaml

@@ -21,4 +21,4 @@ version: 0.1.0
 # incremented each time you make changes to the application. Versions are not expected to
 # follow Semantic Versioning. They should reflect the version the application is using.
 # It is recommended to use it with quotes.
-appVersion: "1.16.0"
+appVersion: "1.2.0"

__tests__/main.test.ts

@@ -82,7 +82,8 @@ describe('run function', () => {
     const gitMock: jest.Mocked<SimpleGit> = {
       status: jest.fn().mockResolvedValue({
         files: [{ path: './**/README.md' }]
-      })
+      }),
+      diff: jest.fn().mockResolvedValue('- old \n+ new ')
     } as any
 
     simpleGitMock.mockReturnValue(gitMock)
@@ -100,6 +101,35 @@ describe('run function', () => {
     expect(gitMock.status).toHaveBeenCalledTimes(1)
 
     expect(setFailedMock).toHaveBeenCalledWith("'README.md' has changed")
+    expect(gitMock.diff).toHaveBeenCalledWith(['--', 'README.md'])
+    expect(infoMock).toHaveBeenCalledWith(
+      "Diff for 'README.md':\n- old \n+ new "
+    )
+    expect(setFailedMock).toHaveBeenCalledWith("'README.md' has changed")
+  })
+
+  it("should handle fail-on-diff === 'true' when diff fails", async () => {
+    installHelmDocsMock.mockResolvedValue('/mocked/path')
+    getInputMock.mockImplementation((inputName: string) => {
+      if (inputName === 'fail-on-diff') {
+        return 'true'
+      }
+      return 'README.md'
+    })
+
+    const gitMock: jest.Mocked<SimpleGit> = {
+      status: jest.fn().mockResolvedValue({
+        files: [{ path: 'README.md' }]
+      }),
+      diff: jest.fn().mockRejectedValue(new Error('diff failed'))
+    } as any
+
+    simpleGitMock.mockReturnValue(gitMock)
+
+    await run()
+
+    expect(gitMock.diff).toHaveBeenCalledWith(['--', 'README.md'])
+    expect(infoMock).toHaveBeenCalledWith("Unable to get diff for 'README.md'")
   })
 
   it("should handle git-push === 'true'", async () => {

src/main.ts

@@ -67,6 +67,12 @@ export async function run(): Promise<void> {
     if (outputStatus.length > 0) {
       switch (true) {
         case failOnDiff === 'true':
+          try {
+            const diff = await git.diff(['--', outputFile])
+            core.info(`Diff for '${outputFile}':\n${diff}`)
+          } catch {
+            core.info(`Unable to get diff for '${outputFile}'`)
+          }
           core.setFailed(`'${outputFile}' has changed`)
           break
         case gitPush === 'true':