Prioritize "readme.md" (#5691)

* prioritize readme.md

* Improve IsReadmeFile

* Add more tests

2 files changed, 29 insertions, 2 deletions

diff --git a/modules/markup/markup.go b/modules/markup/markup.go
index d17270fb01..c506007723 100644
--- a/modules/markup/markup.go
+++ b/modules/markup/markup.go
@@ -111,9 +111,14 @@ func IsMarkupFile(name, markup string) bool {
 }
 
 // IsReadmeFile reports whether name looks like a README file
-// based on its name.
-func IsReadmeFile(name string) bool {
+// 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 {
 	name = strings.ToLower(name)
+	if len(ext) > 0 {
+		return name == "readme"+ext[0]
+	}
 	if len(name) < 6 {
 		return false
 	} else if len(name) == 6 {
diff --git a/modules/markup/markup_test.go b/modules/markup/markup_test.go
index b0ebfae57d..118fa2632b 100644
--- a/modules/markup/markup_test.go
+++ b/modules/markup/markup_test.go
@@ -19,6 +19,7 @@ func TestMisc_IsReadmeFile(t *testing.T) {
 		"README",
 		"readME.mdown",
 		"README.md",
+		"readme.i18n.md",
 	}
 	falseTestCases := []string{
 		"test.md",
@@ -37,4 +38,25 @@ func TestMisc_IsReadmeFile(t *testing.T) {
 	for _, testCase := range falseTestCases {
 		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"},
+	}
+
+	for _, testCase := range trueTestCasesStrict {
+		assert.True(t, IsReadmeFile(testCase[0], testCase[1]))
+	}
+	for _, testCase := range falseTestCasesStrict {
+		assert.False(t, IsReadmeFile(testCase[0], testCase[1]))
+	}
 }