Support localized README (#20508)

* Support localized README

* Slightly simplify getting the readme file and add some tests. Ensure that i18n also
works for docs/ etc.

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Update modules/markup/renderer.go

* Update modules/markup/renderer.go

* Update modules/markup/renderer.go

Co-authored-by: Andrew Thornton <art27@cantab.net>

2 files changed, 65 insertions, 23 deletions

diff --git a/modules/markup/renderer.go b/modules/markup/renderer.go
index e88fa31187..9278d4c65d 100644
--- a/modules/markup/renderer.go
+++ b/modules/markup/renderer.go
@@ -310,14 +310,9 @@ func IsMarkupFile(name, markup string) bool {
 }
 
 // IsReadmeFile reports whether name looks like a README file
-// based on its name. If an extension is provided, it will strictly
-// match that extension.
-// Note that the '.' should be provided in ext, e.g ".md"
-func IsReadmeFile(name string, ext ...string) bool {
+// based on its name.
+func IsReadmeFile(name string) bool {
 	name = strings.ToLower(name)
-	if len(ext) > 0 {
-		return name == "readme"+ext[0]
-	}
 	if len(name) < 6 {
 		return false
 	} else if len(name) == 6 {
@@ -325,3 +320,27 @@ func IsReadmeFile(name string, ext ...string) bool {
 	}
 	return name[:7] == "readme."
 }
+
+// IsReadmeFileExtension reports whether name looks like a README file
+// based on its name. It will look through the provided extensions and check if the file matches
+// one of the extensions and provide the index in the extension list.
+// If the filename is `readme.` with an unmatched extension it will match with the index equaling
+// the length of the provided extension list.
+// Note that the '.' should be provided in ext, e.g ".md"
+func IsReadmeFileExtension(name string, ext ...string) (int, bool) {
+	if len(name) < 6 || name[:6] != "readme" {
+		return 0, false
+	}
+
+	for i, extension := range ext {
+		if name[6:] == extension {
+			return i, true
+		}
+	}
+
+	if name[6] == '.' {
+		return len(ext), true
+	}
+
+	return 0, false
+}
diff --git a/modules/markup/renderer_test.go b/modules/markup/renderer_test.go
index 4cfa022463..1e0f7db194 100644
--- a/modules/markup/renderer_test.go
+++ b/modules/markup/renderer_test.go
@@ -40,24 +40,47 @@ func TestMisc_IsReadmeFile(t *testing.T) {
 		assert.False(t, IsReadmeFile(testCase))
 	}
 
-	trueTestCasesStrict := [][]string{
-		{"readme", ""},
-		{"readme.md", ".md"},
-		{"readme.txt", ".txt"},
-	}
-	falseTestCasesStrict := [][]string{
-		{"readme", ".md"},
-		{"readme.md", ""},
-		{"readme.md", ".txt"},
-		{"readme.md", "md"},
-		{"readmee.md", ".md"},
-		{"readme.i18n.md", ".md"},
+	type extensionTestcase struct {
+		name     string
+		expected bool
+		idx      int
 	}
 
-	for _, testCase := range trueTestCasesStrict {
-		assert.True(t, IsReadmeFile(testCase[0], testCase[1]))
+	exts := []string{".md", ".txt", ""}
+	testCasesExtensions := []extensionTestcase{
+		{
+			name:     "readme",
+			expected: true,
+			idx:      2,
+		},
+		{
+			name:     "readme.md",
+			expected: true,
+			idx:      0,
+		},
+		{
+			name:     "readme.txt",
+			expected: true,
+			idx:      1,
+		},
+		{
+			name:     "readme.doc",
+			expected: true,
+			idx:      3,
+		},
+		{
+			name: "readmee.md",
+		},
+		{
+			name:     "readme..",
+			expected: true,
+			idx:      3,
+		},
 	}
-	for _, testCase := range falseTestCasesStrict {
-		assert.False(t, IsReadmeFile(testCase[0], testCase[1]))
+
+	for _, testCase := range testCasesExtensions {
+		idx, ok := IsReadmeFileExtension(testCase.name, exts...)
+		assert.Equal(t, testCase.expected, ok)
+		assert.Equal(t, testCase.idx, idx)
 	}
 }