Warn when config contains bad URL

main.go

@@ -10,20 +10,20 @@ import (
 func main() {
 	arg, err := processArgs(os.Args)
 	if err != nil {
-		fmt.Printf("error: \"%s\"\n", err)
+		fmt.Fprintf(os.Stderr, "error: \"%s\"\n", err)
 		os.Exit(1)
 	}
 
 	url, err := open.GetURL(arg)
 	if err != nil {
-		fmt.Printf("error: \"%s\"\n", err)
+		fmt.Fprintf(os.Stderr, "error: \"%s\"\n", err)
 		os.Exit(1)
 	}
 
 	fmt.Printf("Opening %s in your browser.\n", url)
 	err = open.InBrowser(url)
 	if err != nil {
-		fmt.Printf("error: unable to open in browser: \"%s\"\n", err)
+		fmt.Fprintf(os.Stderr, "error: unable to open in browser: \"%s\"\n", err)
 		os.Exit(1)
 	}
 }

open/provider.go

@@ -1,7 +1,9 @@
 package open
 
 import (
+	"fmt"
 	"net/url"
+	"os"
 	"strings"
 
 	"github.com/ldez/go-git-cmd-wrapper/v2/config"
@@ -71,6 +73,7 @@ func LoadProviders() []Provider {
 		return p
 	}
 
+	var order []string
 	urls := make(map[string]*Provider)
 	for line := range strings.SplitSeq(out, "\n") {
 		s := strings.SplitN(line, " ", 2)
@@ -95,6 +98,7 @@ func LoadProviders() []Provider {
 		if entry == nil {
 			entry = &Provider{}
 			urls[rawURL] = entry
+			order = append(order, rawURL)
 		}
 
 		switch key {
@@ -105,7 +109,13 @@ func LoadProviders() []Provider {
 		}
 	}
 
-	for k, v := range urls {
+	for _, k := range order {
+		u, err := url.Parse(k)
+		if err != nil || u.Host == "" || (u.Scheme != "http" && u.Scheme != "https") {
+			fmt.Fprintf(os.Stderr, "warning: invalid provider URL in git config: %q\n", k)
+			continue
+		}
+		v := urls[k]
 		v.BaseURL = k
 		p = append(p, *v)
 	}

open/provider_test.go

@@ -1,6 +1,7 @@
 package open
 
 import (
+	"net/url"
 	"os"
 	"path/filepath"
 	"runtime"
@@ -15,6 +16,19 @@ import (
 
 const repo = "arbourd/git-open"
 
+func TestDefaultProviders(t *testing.T) {
+	for _, p := range DefaultProviders {
+		u, err := url.Parse(p.BaseURL)
+		if err != nil {
+			t.Errorf("provider %q: invalid BaseURL: %v", p.BaseURL, err)
+			continue
+		}
+		if u.Host == "" {
+			t.Errorf("provider %q: BaseURL has no host", p.BaseURL)
+		}
+	}
+}
+
 func TestCommitURL(t *testing.T) {
 	cases := map[string]struct {
 		p           Provider
@@ -208,21 +222,34 @@ func TestLoadProviders(t *testing.T) {
 				{BaseURL: "https://git.internal.corp.com", CommitPrefix: "commit", PathPrefix: "tree"},
 			},
 		},
+		"invalid url": {
+			config: []string{
+				"open.not-a-url.commitprefix commit",
+				"open.not-a-url.pathprefix tree",
+			},
+			expectedProviders: []Provider{},
+		},
+		"non-web scheme": {
+			config: []string{
+				"open.ssh://git.example.dev.commitprefix commit",
+				"open.ssh://git.example.dev.pathprefix tree",
+			},
+			expectedProviders: []Provider{},
+		},
 	}
 
 	for name, c := range cases {
 		t.Run(name, func(t *testing.T) {
 			// removes all `open.https://` Git config entries
 			out, _ := git.Config(config.Global, config.GetRegexp(getRegex, ""))
-			for _, v := range strings.Split(strings.TrimSpace(out), "\n") {
-				key := strings.Split(strings.TrimSpace(v), " ")[0]
-
+			for v := range strings.SplitSeq(strings.TrimSpace(out), "\n") {
+				key, _, _ := strings.Cut(strings.TrimSpace(v), " ")
 				git.Config(config.Global, config.Unset(key, ""))
 			}
 
 			for _, v := range c.config {
-				s := strings.Split(v, " ")
-				git.Config(config.Global, config.Entry(s[0], s[1]))
+				key, val, _ := strings.Cut(v, " ")
+				git.Config(config.Global, config.Entry(key, val))
 			}
 
 			p := LoadProviders()