phase2: markdown converter with goldmark, chroma, and ASCII-translit anchors

internal/converter/converter_test.go

@@ -0,0 +1,162 @@
+package converter
+
+import (
+	"bytes"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/fserg/md-to-html/web/template"
+	"github.com/yuin/goldmark/ast"
+	"github.com/yuin/goldmark/text"
+)
+
+func TestGolden(t *testing.T) {
+	c := newTestConverter(t)
+	update := os.Getenv("UPDATE_GOLDEN") == "1"
+
+	entries, err := os.ReadDir("testdata")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	for _, entry := range entries {
+		name := entry.Name()
+		if entry.IsDir() || !strings.HasSuffix(name, ".md") {
+			continue
+		}
+
+		t.Run(name, func(t *testing.T) {
+			md, err := os.ReadFile(filepath.Join("testdata", name))
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			wantPath := filepath.Join("testdata", strings.TrimSuffix(name, ".md")+".html")
+			got, err := c.Convert(md, "Document")
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			for _, forbidden := range []string{"http://", "https://", "cdn.", "googleapis.com"} {
+				if bytes.Contains(got.HTML, []byte(forbidden)) {
+					t.Fatalf("generated HTML contains forbidden external resource marker %q", forbidden)
+				}
+			}
+
+			if update {
+				if err := os.WriteFile(wantPath, got.HTML, 0o644); err != nil {
+					t.Fatal(err)
+				}
+				return
+			}
+
+			want, err := os.ReadFile(wantPath)
+			if err != nil {
+				t.Fatalf("missing golden %s; run UPDATE_GOLDEN=1", wantPath)
+			}
+
+			if !bytes.Equal(got.HTML, want) {
+				t.Errorf("mismatch: run UPDATE_GOLDEN=1 go test ./internal/converter/... to refresh")
+			}
+		})
+	}
+}
+
+func TestTranslitSlug(t *testing.T) {
+	tests := []struct {
+		name string
+		in   string
+		want string
+		used map[string]int
+	}{
+		{name: "cyrillic", in: "Установка", want: "ustanovka", used: map[string]int{}},
+		{name: "collision first", in: "Install", want: "install", used: map[string]int{}},
+		{name: "collision second", in: "Install", want: "install-1", used: map[string]int{"install": 1}},
+		{name: "cyrillic translit", in: "Сетап", want: "setap", used: map[string]int{}},
+		{name: "empty fallback", in: "!!!", want: "section", used: map[string]int{}},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := translitSlug(tt.in, tt.used)
+			if got != tt.want {
+				t.Fatalf("translitSlug(%q) = %q, want %q", tt.in, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestExtractHeadingText(t *testing.T) {
+	c := newTestConverter(t)
+	src := []byte("## [API](https://example.com) `go fmt` https://example.com :rocket:\n")
+	doc := c.md.Parser().Parse(text.NewReader(src))
+
+	var heading *ast.Heading
+	_ = ast.Walk(doc, func(n ast.Node, entering bool) (ast.WalkStatus, error) {
+		if !entering {
+			return ast.WalkContinue, nil
+		}
+		if h, ok := n.(*ast.Heading); ok {
+			heading = h
+			return ast.WalkStop, nil
+		}
+		return ast.WalkContinue, nil
+	})
+
+	if heading == nil {
+		t.Fatal("heading not found")
+	}
+
+	got := extractHeadingText(heading, src)
+	want := "API go fmt https://example.com 🚀"
+	if got != want {
+		t.Fatalf("extractHeadingText() = %q, want %q", got, want)
+	}
+}
+
+func TestConvertTitleFromFirstHeading(t *testing.T) {
+	c := newTestConverter(t)
+
+	result, err := c.Convert([]byte("# Hello\n\nParagraph"), "fallback")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if result.Title != "Hello" {
+		t.Fatalf("result.Title = %q, want %q", result.Title, "Hello")
+	}
+
+	if !bytes.Contains(result.HTML, []byte("<title>Hello</title>")) {
+		t.Fatalf("expected HTML title to contain Hello")
+	}
+}
+
+func TestConvertTitleFallback(t *testing.T) {
+	c := newTestConverter(t)
+
+	result, err := c.Convert([]byte("Paragraph only"), "fallback")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if result.Title != "fallback" {
+		t.Fatalf("result.Title = %q, want %q", result.Title, "fallback")
+	}
+
+	if !bytes.Contains(result.HTML, []byte("<h1>fallback</h1>")) {
+		t.Fatalf("expected fallback h1 to be injected")
+	}
+}
+
+func newTestConverter(t *testing.T) *Converter {
+	t.Helper()
+
+	c, err := New(webtemplate.FS)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	return c
+}