Implement #29 jekyll-readme-index

plugins/readme_index.go

@@ -0,0 +1,57 @@
+package plugins
+
+import (
+	"path"
+	"path/filepath"
+	"strings"
+)
+
+type jekyllReadmeIndexPlugin struct{ plugin }
+
+func init() {
+	register("jekyll-readme-index", jekyllReadmeIndexPlugin{})
+}
+
+func (p jekyllReadmeIndexPlugin) PostInitPage(s Site, page Page) error {
+	if isReadmePage(page) {
+		// Calculate the new URL for this README page
+		oldURL := page.URL()
+		newURL := calculateIndexURL(oldURL)
+
+		// Set the permalink in frontmatter to change the URL
+		if newURL != oldURL {
+			fm := page.FrontMatter()
+			fm["permalink"] = newURL
+		}
+	}
+	return nil
+}
+
+// isReadmePage checks if a page is a README file
+func isReadmePage(page Page) bool {
+	source := page.Source()
+	if source == "" {
+		return false
+	}
+	basename := filepath.Base(source)
+	// Check for README.md, README.markdown, README.mdown, etc.
+	nameWithoutExt := strings.TrimSuffix(basename, filepath.Ext(basename))
+	return strings.EqualFold(nameWithoutExt, "README")
+}
+
+// calculateIndexURL converts a README URL to its index URL
+// e.g., "/README.html" -> "/"
+//
+//	"/foo/README.html" -> "/foo/"
+//	"/foo/bar/README.html" -> "/foo/bar/"
+func calculateIndexURL(url string) string {
+	dir := path.Dir(url)
+	if dir == "." || dir == "" {
+		return "/"
+	}
+	// Ensure the directory path ends with a slash
+	if !strings.HasSuffix(dir, "/") {
+		dir += "/"
+	}
+	return dir
+}

plugins/readme_index_test.go

@@ -0,0 +1,130 @@
+package plugins
+
+import (
+	"testing"
+
+	"github.com/osteele/gojekyll/pages"
+	"github.com/stretchr/testify/require"
+)
+
+func TestIsReadmePage(t *testing.T) {
+	tests := []struct {
+		name     string
+		source   string
+		expected bool
+	}{
+		{"root README.md", "/path/to/site/README.md", true},
+		{"root README.markdown", "/path/to/site/README.markdown", true},
+		{"nested README.md", "/path/to/site/foo/README.md", true},
+		{"nested README.markdown", "/path/to/site/foo/bar/README.markdown", true},
+		{"case insensitive", "/path/to/site/readme.md", true},
+		{"not a README", "/path/to/site/index.md", false},
+		{"empty source", "", false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Create a mock page with source in frontmatter
+			fm := make(pages.FrontMatter)
+			page := &mockPage{fm: fm}
+			// Override the Source method by creating a custom page wrapper
+			testPage := &testPageWithSource{
+				Page:   page,
+				source: tt.source,
+			}
+			result := isReadmePage(testPage)
+			require.Equal(t, tt.expected, result)
+		})
+	}
+}
+
+// testPageWithSource wraps mockPage to provide a custom Source method
+type testPageWithSource struct {
+	Page
+	source string
+}
+
+func (p *testPageWithSource) Source() string {
+	return p.source
+}
+
+func TestCalculateIndexURL(t *testing.T) {
+	tests := []struct {
+		name     string
+		url      string
+		expected string
+	}{
+		{"root README", "/README.html", "/"},
+		{"one level deep", "/foo/README.html", "/foo/"},
+		{"two levels deep", "/foo/bar/README.html", "/foo/bar/"},
+		{"already has slash", "/foo/", "/foo/"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := calculateIndexURL(tt.url)
+			require.Equal(t, tt.expected, result)
+		})
+	}
+}
+
+func TestReadmeIndexPlugin_PostInitPage(t *testing.T) {
+	plugin := jekyllReadmeIndexPlugin{}
+	site := &mockSite{}
+
+	tests := []struct {
+		name            string
+		source          string
+		url             string
+		expectedChanged bool
+		expectedURL     string
+	}{
+		{
+			name:            "root README",
+			source:          "/path/to/site/README.md",
+			url:             "/README.html",
+			expectedChanged: true,
+			expectedURL:     "/",
+		},
+		{
+			name:            "nested README",
+			source:          "/path/to/site/foo/README.md",
+			url:             "/foo/README.html",
+			expectedChanged: true,
+			expectedURL:     "/foo/",
+		},
+		{
+			name:            "non-README page",
+			source:          "/path/to/site/index.md",
+			url:             "/index.html",
+			expectedChanged: false,
+			expectedURL:     "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			fm := make(pages.FrontMatter)
+			page := &mockPage{
+				url: tt.url,
+				fm:  fm,
+			}
+			testPage := &testPageWithSource{
+				Page:   page,
+				source: tt.source,
+			}
+
+			err := plugin.PostInitPage(site, testPage)
+			require.NoError(t, err)
+
+			if tt.expectedChanged {
+				permalink, hasPermalink := fm["permalink"]
+				require.True(t, hasPermalink, "permalink should be set in frontmatter")
+				require.Equal(t, tt.expectedURL, permalink)
+			} else {
+				_, hasPermalink := fm["permalink"]
+				require.False(t, hasPermalink, "permalink should not be set for non-README pages")
+			}
+		})
+	}
+}