Add end-to-end suite

.github/workflows/e2e.yml

@@ -0,0 +1,41 @@
+name: E2E
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+# Every run shares the test account's rate limit, so only one run goes at a
+# time. A newer pending run replaces an older pending one.
+concurrency:
+  group: e2e-test-account
+  cancel-in-progress: false
+
+jobs:
+  e2e:
+    name: E2E (${{ matrix.os }})
+    strategy:
+      fail-fast: false
+      # The jobs share the test account's rate limit, so running them one at a
+      # time keeps TestRateLimit's bursts from colliding.
+      max-parallel: 1
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+    env:
+      # Secrets aren't passed to pull requests from forks, so the tests skip
+      # themselves when the key is empty.
+      EMAILABLE_TEST_API_KEY: ${{ secrets.EMAILABLE_TEST_API_KEY }}
+    steps:
+      - uses: actions/checkout@v6
+
+      - uses: actions/setup-go@v6
+        with:
+          go-version-file: go.mod
+
+      - name: Test
+        run: go test -tags e2e -count=1 -v ./e2e

Makefile

@@ -1,4 +1,4 @@
-.PHONY: build test fmt lint clean run release release-snapshot man
+.PHONY: build test test-e2e fmt lint clean run release release-snapshot man
 
 BINARY := emailable
 PKG    := .
@@ -10,6 +10,11 @@ build:
 test:
 	go test -race -coverprofile=coverage.txt ./...
 
+# Runs the built binary against the real API. Requires EMAILABLE_TEST_API_KEY
+# set to a test key (test_...), which spends no credits.
+test-e2e:
+	go test -tags e2e -count=1 -v ./e2e
+
 fmt:
 	gofmt -w .
 

README.md

@@ -572,6 +572,8 @@ Common targets:
 
 - `make build` — compile to `bin/emailable`
 - `make test` — run tests with race detector and coverage
+- `make test-e2e` — run the built binary against the real API; requires
+  `EMAILABLE_TEST_API_KEY` set to a test key (`test_...`)
 - `make fmt` — format with `gofmt`
 - `make lint` — run `golangci-lint`
 - `make release VERSION=x.y.z` — bump `plugin.json`, commit, and tag `vx.y.z`