Add: Support running tests in a working directory (#7)

* Add working-directory input to run tests in a subdirectory

README.md

@@ -60,4 +60,17 @@ with:
   coverage-comment: false
 ```
 
+### Running tests in a subdirectory
+
+For running tests in folders other than root, supply a working-directory.
+
+```yaml
+uses: mattallty/jest-github-action@v1
+env:
+  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+with:
+  working-directory: "frontend"
+```
+
+
 See the [actions tab](https://github.com/mattallty/jest-github-action/actions) for runs of this action! :rocket:

action.yml

@@ -8,6 +8,10 @@ inputs:
     description: "The test command to run"
     required: false
     default: "npm test"
+  working-directory:
+    description: "Subdirectory to run tests in"
+    required: false
+    default: ""
   coverage-comment:
     description: "Comment PRs with code coverage"
     required: false

src/action.ts

@@ -1,4 +1,4 @@
-import { sep, join } from "path"
+import { sep, join, resolve } from "path"
 import { readFileSync } from "fs"
 import { exec } from "@actions/exec"
 import * as core from "@actions/core"
@@ -16,7 +16,9 @@ const ACTION_NAME = "jest-github-action"
 const COVERAGE_HEADER = ":loop: **Code coverage**\n\n"
 
 export async function run() {
-  const CWD = process.cwd() + sep
+  let workingDirectory = core.getInput("working-directory", { required: false })
+  let cwd = workingDirectory ? resolve(workingDirectory) : process.cwd()
+  const CWD = cwd + sep
   const RESULTS_FILE = join(CWD, "jest.results.json")
 
   try {
@@ -29,7 +31,7 @@ export async function run() {
 
     const cmd = getJestCommand(RESULTS_FILE)
 
-    await execJest(cmd)
+    await execJest(cmd, CWD)
 
     // octokit
     const octokit = new GitHub(token)
@@ -166,12 +168,12 @@ function parseResults(resultsFile: string): FormattedTestResults {
   return results
 }
 
-async function execJest(cmd: string) {
+async function execJest(cmd: string, cwd?: string) {
   try {
-    await exec(cmd, [], { silent: true })
+    await exec(cmd, [], { silent: true, cwd })
     console.debug("Jest command executed")
   } catch (e) {
-    console.debug("Jest execution failed. Tests have likely failed.")
+    console.error("Jest execution failed. Tests have likely failed.", e)
   }
 }