Add test code and CI test.

.github/workflows/test.yml

@@ -0,0 +1,40 @@
+name: Test
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+        go: ["1.21", "1.20"]
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - name: Set up Go
+        uses: actions/setup-go@v4
+        with:
+          go-version: ${{ matrix.go }}
+
+      - name: Check out code
+        uses: actions/checkout@v3
+
+      - name: Restore Go modules cache
+        uses: actions/cache@v3
+        with:
+          path: ~/go/pkg/mod
+          key: go-${{ runner.os }}-${{ hashFiles('go.mod') }}
+          restore-keys: |
+            go-${{ runner.os }}-
+
+      - name: Download dependencies
+        run: go mod download
+
+      - name: Run tests
+        run: go test -race ./...
+
+      - name: Build
+        run: go build -v ./...

.gitignore

@@ -19,3 +19,15 @@
 
 # Go workspace file
 go.work
+
+# macOS
+.DS_Store
+
+# VS Code
+.vscode
+
+# IntelliJ
+.idea
+
+# vim
+*.swp

Makefile

@@ -0,0 +1,3 @@
+.PHONY: test
+test:
+	go test ./...

client_test.go

@@ -0,0 +1,266 @@
+package testclient
+
+import (
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type TestHandler struct {
+	Path       string
+	Method     string
+	Response   string
+	StatusCode int
+	Middleware func(t *testing.T, w http.ResponseWriter, r *http.Request)
+}
+
+func createTestServer(t *testing.T, handlers []TestHandler) http.Handler {
+	mux := http.NewServeMux()
+
+	for _, h := range handlers {
+		handler := h // For closure
+		mux.HandleFunc(handler.Path, func(w http.ResponseWriter, r *http.Request) {
+			assert.Equal(t, handler.Method, r.Method)
+
+			if handler.Middleware != nil {
+				handler.Middleware(t, w, r)
+			}
+
+			w.WriteHeader(handler.StatusCode)
+			_, _ = w.Write([]byte(handler.Response))
+		})
+	}
+
+	return mux
+}
+
+func TestClient_New(t *testing.T) {
+	server := http.NewServeMux()
+	client := New(server)
+	assert.NotNil(t, client)
+}
+
+func TestClient_Request(t *testing.T) {
+	type want struct {
+		code int
+		body string
+	}
+	tests := []struct {
+		name     string
+		path     string
+		method   string
+		handlers []TestHandler
+		want     want
+	}{
+		{
+			name:   "When request is GET",
+			path:   "/get",
+			method: http.MethodGet,
+			handlers: []TestHandler{
+				{
+					Path:       "/get",
+					Method:     http.MethodGet,
+					StatusCode: http.StatusOK,
+					Response:   "ok",
+				},
+			},
+			want: want{
+				code: http.StatusOK,
+				body: "ok",
+			},
+		},
+		{
+			name:   "When request is POST",
+			path:   "/post",
+			method: http.MethodPost,
+			handlers: []TestHandler{
+				{
+					Path:       "/post",
+					Method:     http.MethodPost,
+					StatusCode: http.StatusOK,
+					Response:   "ok",
+				},
+			},
+			want: want{
+				code: http.StatusOK,
+				body: "ok",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			server := createTestServer(t, tt.handlers)
+			client := New(server)
+			req := httptest.NewRequest(tt.method, tt.path, nil)
+			client.Request(req)
+			res := client.Response()
+
+			assert.Equal(t, tt.want.code, res.StatusCode)
+
+			body, _ := io.ReadAll(res.Body)
+			assert.Equal(t, tt.want.body, string(body))
+		})
+	}
+}
+
+func TestClient_PostForm(t *testing.T) {
+	type want struct {
+		code int
+		body string
+	}
+	tests := []struct {
+		name     string
+		path     string
+		params   map[string]string
+		handlers []TestHandler
+		want     want
+	}{
+		{
+			name: "When request has some parameters",
+			path: "/post",
+			params: map[string]string{
+				"key1": "value1",
+				"key2": "value2",
+			},
+			handlers: []TestHandler{
+				{
+					Path:       "/post",
+					Method:     http.MethodPost,
+					StatusCode: http.StatusOK,
+					Response:   "ok",
+					Middleware: func(t *testing.T, w http.ResponseWriter, r *http.Request) {
+						contentType := r.Header.Get("Content-Type")
+						assert.Equal(t, "application/x-www-form-urlencoded", contentType)
+
+						err := r.ParseForm()
+						assert.NoError(t, err)
+
+						assert.Equal(t, "value1", r.PostFormValue("key1"))
+						assert.Equal(t, "value2", r.PostFormValue("key2"))
+					},
+				},
+			},
+			want: want{
+				code: http.StatusOK,
+				body: "ok",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			server := createTestServer(t, tt.handlers)
+			client := New(server)
+			client.PostForm(tt.path, tt.params)
+			res := client.Response()
+
+			assert.Equal(t, tt.want.code, res.StatusCode)
+
+			body, _ := io.ReadAll(res.Body)
+			assert.Equal(t, tt.want.body, string(body))
+		})
+	}
+}
+
+func TestClient_FollowRedirect(t *testing.T) {
+	type want struct {
+		code int
+		body string
+	}
+	tests := []struct {
+		name     string
+		path     string
+		params   map[string]string
+		handlers []TestHandler
+		want     want
+		wantErr  bool
+	}{
+		{
+			name: "When redirect with cookie",
+			path: "/redirect",
+			handlers: []TestHandler{
+				{
+					Path:       "/redirect",
+					Method:     http.MethodGet,
+					StatusCode: http.StatusFound,
+					Middleware: func(t *testing.T, w http.ResponseWriter, r *http.Request) {
+						http.SetCookie(w, &http.Cookie{
+							Name:  "cookie",
+							Value: "candy",
+						})
+						http.Redirect(w, r, "/target", http.StatusFound)
+					},
+				},
+				{
+					Path:       "/target",
+					Method:     http.MethodGet,
+					Response:   "ok",
+					StatusCode: http.StatusOK,
+					Middleware: func(t *testing.T, w http.ResponseWriter, r *http.Request) {
+						cookie, err := r.Cookie("cookie")
+						assert.NoError(t, err)
+						assert.Equal(t, "candy", cookie.Value)
+					},
+				},
+			},
+			want: want{
+				code: http.StatusOK,
+				body: "ok",
+			},
+			wantErr: false,
+		},
+		{
+			name: "When no redirect",
+			path: "/no-redirect",
+			handlers: []TestHandler{
+				{
+					Path:       "/no-redirect",
+					Method:     http.MethodGet,
+					Response:   "ok",
+					StatusCode: http.StatusOK,
+				},
+			},
+			want:    want{},
+			wantErr: true,
+		},
+		{
+			name: "When no location header",
+			path: "/no-location",
+			handlers: []TestHandler{
+				{
+					Path:       "/no-location",
+					Method:     http.MethodGet,
+					Response:   "ok",
+					StatusCode: http.StatusFound,
+				},
+			},
+			want:    want{},
+			wantErr: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			server := createTestServer(t, tt.handlers)
+			client := New(server)
+			req := httptest.NewRequest(http.MethodGet, tt.path, nil)
+			client.Request(req)
+
+			err := client.FollowRedirect()
+			if tt.wantErr {
+				assert.Error(t, err)
+				return
+			}
+
+			res := client.Response()
+			assert.Equal(t, tt.want.code, res.StatusCode)
+
+			body, _ := io.ReadAll(res.Body)
+			assert.Equal(t, tt.want.body, string(body))
+		})
+	}
+}

go.mod

@@ -1,3 +1,13 @@
 module github.com/raksul/go-testclient
 
-go 1.21.0
+// Specify to the minimum version that is supported in testing.
+// .github/workflows/test.yml
+go 1.20
+
+require github.com/stretchr/testify v1.8.4
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -0,0 +1,10 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=