1 files changed, 220 insertions, 0 deletions
diff --git a/src/mime/type_test.go b/src/mime/type_test.go
new file mode 100644
index 0000000..d8368e8
--- /dev/null
+++ b/src/mime/type_test.go
@@ -0,0 +1,220 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+import (
+	"reflect"
+	"strings"
+	"sync"
+	"testing"
+)
+
+func setMimeInit(fn func()) (cleanup func()) {
+	once = sync.Once{}
+	testInitMime = fn
+	return func() {
+		testInitMime = nil
+		once = sync.Once{}
+	}
+}
+
+func clearMimeTypes() {
+	setMimeTypes(map[string]string{}, map[string]string{})
+}
+
+func setType(ext, typ string) {
+	if !strings.HasPrefix(ext, ".") {
+		panic("missing leading dot")
+	}
+	if err := setExtensionType(ext, typ); err != nil {
+		panic("bad test data: " + err.Error())
+	}
+}
+
+func TestTypeByExtension(t *testing.T) {
+	once = sync.Once{}
+	// initMimeForTests returns the platform-specific extension =>
+	// type tests. On Unix and Plan 9, this also tests the parsing
+	// of MIME text files (in testdata/*). On Windows, we test the
+	// real registry on the machine and assume that ".png" exists
+	// there, which empirically it always has, for all versions of
+	// Windows.
+	typeTests := initMimeForTests()
+
+	for ext, want := range typeTests {
+		val := TypeByExtension(ext)
+		if val != want {
+			t.Errorf("TypeByExtension(%q) = %q, want %q", ext, val, want)
+		}
+	}
+}
+
+func TestTypeByExtension_LocalData(t *testing.T) {
+	cleanup := setMimeInit(func() {
+		clearMimeTypes()
+		setType(".foo", "x/foo")
+		setType(".bar", "x/bar")
+		setType(".Bar", "x/bar; capital=1")
+	})
+	defer cleanup()
+
+	tests := map[string]string{
+		".foo":          "x/foo",
+		".bar":          "x/bar",
+		".Bar":          "x/bar; capital=1",
+		".sdlkfjskdlfj": "",
+		".t1":           "", // testdata shouldn't be used
+	}
+
+	for ext, want := range tests {
+		val := TypeByExtension(ext)
+		if val != want {
+			t.Errorf("TypeByExtension(%q) = %q, want %q", ext, val, want)
+		}
+	}
+}
+
+func TestTypeByExtensionCase(t *testing.T) {
+	const custom = "test/test; charset=iso-8859-1"
+	const caps = "test/test; WAS=ALLCAPS"
+
+	cleanup := setMimeInit(func() {
+		clearMimeTypes()
+		setType(".TEST", caps)
+		setType(".tesT", custom)
+	})
+	defer cleanup()
+
+	// case-sensitive lookup
+	if got := TypeByExtension(".tesT"); got != custom {
+		t.Fatalf("for .tesT, got %q; want %q", got, custom)
+	}
+	if got := TypeByExtension(".TEST"); got != caps {
+		t.Fatalf("for .TEST, got %q; want %s", got, caps)
+	}
+
+	// case-insensitive
+	if got := TypeByExtension(".TesT"); got != custom {
+		t.Fatalf("for .TesT, got %q; want %q", got, custom)
+	}
+}
+
+func TestExtensionsByType(t *testing.T) {
+	cleanup := setMimeInit(func() {
+		clearMimeTypes()
+		setType(".gif", "image/gif")
+		setType(".a", "foo/letter")
+		setType(".b", "foo/letter")
+		setType(".B", "foo/letter")
+		setType(".PNG", "image/png")
+	})
+	defer cleanup()
+
+	tests := []struct {
+		typ     string
+		want    []string
+		wantErr string
+	}{
+		{typ: "image/gif", want: []string{".gif"}},
+		{typ: "image/png", want: []string{".png"}}, // lowercase
+		{typ: "foo/letter", want: []string{".a", ".b"}},
+		{typ: "x/unknown", want: nil},
+	}
+
+	for _, tt := range tests {
+		got, err := ExtensionsByType(tt.typ)
+		if err != nil && tt.wantErr != "" && strings.Contains(err.Error(), tt.wantErr) {
+			continue
+		}
+		if err != nil {
+			t.Errorf("ExtensionsByType(%q) error: %v", tt.typ, err)
+			continue
+		}
+		if tt.wantErr != "" {
+			t.Errorf("ExtensionsByType(%q) = %q, %v; want error substring %q", tt.typ, got, err, tt.wantErr)
+			continue
+		}
+		if !reflect.DeepEqual(got, tt.want) {
+			t.Errorf("ExtensionsByType(%q) = %q; want %q", tt.typ, got, tt.want)
+		}
+	}
+}
+
+func TestLookupMallocs(t *testing.T) {
+	n := testing.AllocsPerRun(10000, func() {
+		TypeByExtension(".html")
+		TypeByExtension(".HtML")
+	})
+	if n > 0 {
+		t.Errorf("allocs = %v; want 0", n)
+	}
+}
+
+func BenchmarkTypeByExtension(b *testing.B) {
+	initMime()
+	b.ResetTimer()
+
+	for _, ext := range []string{
+		".html",
+		".HTML",
+		".unused",
+	} {
+		b.Run(ext, func(b *testing.B) {
+			b.RunParallel(func(pb *testing.PB) {
+				for pb.Next() {
+					TypeByExtension(ext)
+				}
+			})
+		})
+	}
+}
+
+func BenchmarkExtensionsByType(b *testing.B) {
+	initMime()
+	b.ResetTimer()
+
+	for _, typ := range []string{
+		"text/html",
+		"text/html; charset=utf-8",
+		"application/octet-stream",
+	} {
+		b.Run(typ, func(b *testing.B) {
+			b.RunParallel(func(pb *testing.PB) {
+				for pb.Next() {
+					if _, err := ExtensionsByType(typ); err != nil {
+						b.Fatal(err)
+					}
+				}
+			})
+		})
+	}
+}
+
+func TestExtensionsByType2(t *testing.T) {
+	cleanup := setMimeInit(func() {
+		clearMimeTypes()
+		// Initialize built-in types like in type.go before osInitMime.
+		setMimeTypes(builtinTypesLower, builtinTypesLower)
+	})
+	defer cleanup()
+
+	tests := []struct {
+		typ  string
+		want []string
+	}{
+		{typ: "image/jpeg", want: []string{".jpeg", ".jpg"}},
+	}
+
+	for _, tt := range tests {
+		got, err := ExtensionsByType(tt.typ)
+		if err != nil {
+			t.Errorf("ExtensionsByType(%q): %v", tt.typ, err)
+			continue
+		}
+		if !reflect.DeepEqual(got, tt.want) {
+			t.Errorf("ExtensionsByType(%q) = %q; want %q", tt.typ, got, tt.want)
+		}
+	}
+}