Add posts.ExtractTitle func

posts/parse.go

@@ -0,0 +1,19 @@
+package posts
+
+import (
+	"strings"
+)
+
+func ExtractTitle(content string) (title string, body string) {
+	if hashIndex := strings.Index(content, "# "); hashIndex == 0 {
+		eol := strings.IndexRune(content, '\n')
+		// First line should start with # and end with \n
+		if eol != -1 {
+			body = strings.TrimLeft(content[eol:], " \t\n\r")
+			title = content[len("# "):eol]
+			return
+		}
+	}
+	body = content
+	return
+}

posts/parse_test.go

@@ -0,0 +1,35 @@
+package posts
+
+import (
+	"testing"
+)
+
+type titleTest struct {
+	in, title, body string
+}
+
+func TestExtractTitle(t *testing.T) {
+	tests := []titleTest{
+		{`# Hello World
+This is my post`, "Hello World", "This is my post"},
+		{"No title", "", "No title"},
+		{`Not explicit title
+
+It's not explicit.
+Yep.`, "", `Not explicit title
+
+It's not explicit.
+Yep.`},
+		{"# Only a title", "", "# Only a title"},
+	}
+
+	for _, test := range tests {
+		title, body := ExtractTitle(test.in)
+		if title != test.title {
+			t.Fatalf("Wanted title '%s', got '%s'", test.title, title)
+		}
+		if body != test.body {
+			t.Fatalf("Wanted body '%s', got '%s'", test.body, body)
+		}
+	}
+}