Introduce JoinURL() helper method (#24)

go.sum

@@ -79,6 +79,7 @@ golang.org/x/mod v0.3.0 h1:RM4zey1++hCTbCVQfnWeKs9/IEsaBLA8vTkd0WVtmH4=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20201021035429-f5854403a974 h1:IX6qOQeG5uLjB/hjjwjedwfjND0hgjPMMyO1RoIXQNI=
 golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -93,6 +94,7 @@ golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f h1:+Nyd8tzPX9R7BWHguqsrbFdRx3WQ/1ib8I44HXV5yTA=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.3 h1:cokOdA+Jmi5PJGXLlLllQSgYigAEfHXJAERHVMaCc2k=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=

hit_test.go

@@ -719,3 +719,97 @@ func TestNoUserAgent(t *testing.T) {
 
 	Test(t, Get(s.URL))
 }
+
+func TestJoinURL(t *testing.T) {
+	tests := []struct {
+		Params   []string
+		Expected string
+	}{
+		{
+			[]string{
+				"http://example.com",
+				"index.html",
+			},
+			"http://example.com/index.html",
+		},
+		{
+			[]string{
+				"http://example.com/",
+				"index.html",
+			},
+			"http://example.com/index.html",
+		},
+		{
+			[]string{
+				"http://example.com",
+				"/index.html",
+			},
+			"http://example.com/index.html",
+		},
+		{
+			[]string{
+				"http://example.com",
+				"",
+			},
+			"http://example.com",
+		},
+		{
+			[]string{
+				"http://example.com/",
+				"",
+			},
+			"http://example.com",
+		},
+		{
+			[]string{
+				"",
+				"index.html",
+			},
+			"index.html",
+		},
+		{
+			[]string{
+				"",
+				"/index.html",
+			},
+			"/index.html",
+		},
+		{
+			[]string{
+				"/index.html",
+			},
+			"/index.html",
+		},
+		{
+			[]string{
+				"http://",
+				"example.com",
+				"index.html",
+			},
+			"http://example.com/index.html",
+		},
+		{
+			[]string{
+				"http://",
+				"/example.com/",
+				"/index.html/",
+			},
+			"http://example.com/index.html",
+		},
+		{
+			[]string{
+				"example.com",
+				"index.html",
+			},
+			"example.com/index.html",
+		},
+	}
+	for i := range tests {
+		test := tests[i]
+		t.Run("", func(t *testing.T) {
+			if s := JoinURL(test.Params...); s != test.Expected {
+				t.Errorf("expected `%s' got `%s'", test.Expected, s)
+			}
+		})
+	}
+}

internal/misc/misc_test.go

@@ -11,48 +11,68 @@ func TestMakeURL(t *testing.T) {
 	tests := []struct {
 		Base     string
 		URL      string
+		Params   []interface{}
 		Expected string
 	}{
 		{
 			"http://example.com",
 			"index.html",
+			nil,
 			"http://example.com/index.html",
 		},
 		{
 			"http://example.com/",
 			"index.html",
+			nil,
 			"http://example.com/index.html",
 		},
 		{
 			"http://example.com",
 			"/index.html",
+			nil,
 			"http://example.com/index.html",
 		},
 		{
 			"http://example.com",
 			"",
+			nil,
 			"http://example.com",
 		},
 		{
 			"http://example.com/",
 			"",
+			nil,
 			"http://example.com/",
 		},
 		{
 			"",
 			"index.html",
+			nil,
 			"index.html",
 		},
 		{
 			"",
 			"/index.html",
+			nil,
 			"/index.html",
 		},
+		{
+			"http://example.com",
+			"%s.%s",
+			[]interface{}{"index", "html"},
+			"http://example.com/index.html",
+		},
+		{
+			"http://example.com",
+			"%s",
+			nil,
+			"http://example.com/%s",
+		},
 	}
 	for i := range tests {
 		test := tests[i]
 		t.Run("", func(t *testing.T) {
-			if s := MakeURL(test.Base, test.URL); s != test.Expected {
+			if s := MakeURL(test.Base, test.URL, test.Params...); s != test.Expected {
 				t.Errorf("expected `%s' got `%s'", test.Expected, s)
 			}
 		})

static.go

@@ -5,6 +5,7 @@ import (
 	"io"
 	"net/http"
 	"os"
+	"strings"
 
 	"github.com/Eun/go-hit/internal/misc"
 
@@ -566,3 +567,46 @@ func Context(ctx context.Context) IStep {
 		},
 	}
 }
+
+// JoinURL joins the specified parts to one url.
+//
+// Example:
+//     JoinURL("https://example.com", "folder", "file") // will return "https://example.com/folder/file"
+//     JoinURL("https://example.com", "index.html")     // will return "https://example.com/index.html"
+//     JoinURL("https://", "example.com", "index.html") // will return "https://example.com/index.html"
+//     JoinURL("example.com", "index.html") // will return "example.com/index.html"
+//     MustDo(
+//         Get(JoinURL("https://example.com", "index.html")),
+//     )
+func JoinURL(parts ...string) string {
+	if len(parts) == 0 {
+		return ""
+	}
+
+	notEmptyParts := make([]string, 0, len(parts))
+	for _, part := range parts {
+		if part == "" {
+			continue
+		}
+		notEmptyParts = append(notEmptyParts, part)
+	}
+	if len(notEmptyParts) == 0 {
+		return ""
+	}
+
+	u, err := urlpkg.Parse(strings.Join(notEmptyParts, "/"))
+	if err != nil {
+		return ""
+	}
+
+	// replace all "double slashes"
+	for {
+		old := u.Path
+		u.Path = strings.ReplaceAll(u.Path, "//", "/")
+		if old == u.Path {
+			break
+		}
+	}
+
+	return strings.TrimRight(strings.ReplaceAll(u.String(), ":///", "://"), "/")
+}