tests for context.Include

middleware/context_test.go

+package middleware
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestInclude(t *testing.T) {
+	context := initTempContext()
+
+	inputFilename := "test_file"
+	absInFilePath := filepath.Join(fmt.Sprintf("%s", context.Root), inputFilename)
+	defer func() {
+		err := os.Remove(absInFilePath)
+		if err != nil && !os.IsNotExist(err) {
+			t.Fatalf("Failed to clean test file!")
+		}
+	}()
+
+	tests := []struct {
+		fileContent          string
+		expectedContent      string
+		shouldErr            bool
+		expectedErrorContent string
+	}{
+		// Test 0 - all good
+		{
+			fileContent:          `str1 {{ .Root }} str2`,
+			expectedContent:      fmt.Sprintf("str1 %s str2", context.Root),
+			shouldErr:            false,
+			expectedErrorContent: "",
+		},
+		// Test 1 - failure on template.Parse
+		{
+			fileContent:          `str1 {{ .Root } str2`,
+			expectedContent:      "",
+			shouldErr:            true,
+			expectedErrorContent: `unexpected "}" in operand`,
+		},
+		// Test 3 - failure on template.Execute
+		{
+			fileContent:          `str1 {{ .InvalidField }} str2`,
+			expectedContent:      "",
+			shouldErr:            false,
+			expectedErrorContent: `InvalidField is not a field of struct type middleware.Context`,
+		},
+	}
+
+	for i, test := range tests {
+		testPrefix := fmt.Sprintf("Test [%d]: ", i)
+
+		// WriteFile truncates the contentt
+		err := ioutil.WriteFile(absInFilePath, []byte(test.fileContent), os.ModePerm)
+		if err != nil {
+			t.Fatal(testPrefix+"Failed to create test file. Error was: %v", err)
+		}
+
+		content, err := context.Include(inputFilename)
+		if err != nil {
+			if !strings.Contains(err.Error(), test.expectedErrorContent) {
+				t.Errorf(testPrefix+"Expected error content [%s], found [%s]", test.expectedErrorContent, err.Error())
+			}
+		}
+
+		if err == nil && test.shouldErr {
+			t.Errorf(testPrefix+"Expected error [%s] but found nil. Input file was: %s", test.expectedErrorContent, inputFilename)
+		}
+
+		if content != test.expectedContent {
+			t.Errorf(testPrefix+"Expected content [%s] but found [%s]. Input file was: %s", test.expectedContent, content, inputFilename)
+		}
+	}
+}
+
+func TestIncludeNotExisting(t *testing.T) {
+	context := initTempContext()
+
+	_, err := context.Include("not_existing")
+	if err == nil {
+		t.Errorf("Expected error but found nil!")
+	}
+}
+
+func initTempContext() Context {
+	rootDir := getTestFilesFolder()
+	return Context{Root: http.Dir(rootDir)}
+}
+
+func getTestFilesFolder() string {
+	return os.TempDir()
+}