Merge pull request #1 from wneessen/subcap-test

Added README.md and test coverage to subject_capitalize

subject_capitalize/README.md

@@ -0,0 +1,33 @@
+<!--
+SPDX-FileCopyrightText: 2022 Winni Neessen <[email protected]>
+
+SPDX-License-Identifier: CC0-1.0
+-->
+
+## Capitalize your subject based on a given language
+
+This is a simple middlware that makes use of the powerful [golang.org/x/text/cases](https://golang.org/x/text/cases)
+library. It will read the currently set subject of the `mail.Msg` and use the `cases` library to capitalize the
+subject based on the given language.
+
+### Example
+```go
+package main
+
+import (
+	"fmt"
+	"github.com/wneessen/go-mail"
+	"github.com/wneessen/go-mail-middleware/subject_capitalize"
+	"golang.org/x/text/language"
+	"os"
+)
+
+func main() {
+	m := mail.NewMsg(mail.WithMiddleware(subcap.New(language.English)))
+	m.Subject("this is a test message")
+	if err := m.WriteToFile("testmail.eml"); err != nil {
+		fmt.Printf("failed to write mail message to file: %s\n", err)
+		os.Exit(1)
+	}
+}
+```

subject_capitalize/subject_capitalize_test.go

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+// SPDX-FileCopyrightText: 2022 Winni Neessen <[email protected]>
+//
+// SPDX-License-Identifier: MIT
+
+package subcap
+
+import (
+	"bytes"
+	"fmt"
+	"github.com/wneessen/go-mail"
+	"golang.org/x/text/language"
+	"strings"
+	"testing"
+)
+
+func TestNew(t *testing.T) {
+	mw := New(language.English)
+	if fmt.Sprintf("%s", mw.l) != "en" {
+		t.Errorf("New() failed. Expected language: %q, got: %q", "en", fmt.Sprintf("%s", mw.l))
+	}
+}
+
+func TestMiddleware_Handle(t *testing.T) {
+	m := mail.NewMsg(mail.WithMiddleware(New(language.English)))
+	m.Subject("this is a test")
+	buf := bytes.Buffer{}
+	if _, err := m.WriteTo(&buf); err != nil {
+		t.Errorf("failed to write mail message to buffer: %s", err)
+	}
+	if !strings.Contains(buf.String(), "This Is A Test") {
+		t.Errorf("middleware failed. Expected: %q in subject, got: %q", "This Is A Test", buf.String())
+	}
+}