fix(open): always try specific MIME type patterns before patterns ending in *

2 files changed, 46 insertions, 2 deletions

diff --git a/programs/open/main.go b/programs/open/main.go
index f193f3f..f5a9204 100644
--- a/programs/open/main.go
+++ b/programs/open/main.go
@@ -3,12 +3,14 @@ package main
 import (
 	"fmt"
 	"log"
+	"maps"
 	"mime"
 	"net/url"
 	"os"
 	"os/exec"
 	"path"
 	"path/filepath"
+	"slices"
 	"strings"
 
 	"github.com/BurntSushi/toml"
@@ -88,13 +90,27 @@ func (c Config) findCommand(arg string) ([]string, error) {
 		mimeType, _, _ = strings.Cut(mimeType, ";")
 	}
 
-	for mimeTypePat, cmd := range c.MimeTypes {
+	sortedMimeTypes := slices.SortedFunc(maps.Keys(c.MimeTypes), func(a, b string) int {
+		aStar := strings.HasSuffix(a, "*")
+		bStar := strings.HasSuffix(b, "*")
+
+		// put patterns ending with * last
+		if aStar && !bStar {
+			return 1
+		} else if !aStar && bStar {
+			return -1
+		}
+
+		return strings.Compare(a, b)
+	})
+
+	for _, mimeTypePat := range sortedMimeTypes {
 		matched, err := path.Match(mimeTypePat, mimeType)
 		if err != nil {
 			return nil, err
 		}
 		if matched {
-			return cmd, nil
+			return c.MimeTypes[mimeTypePat], nil
 		}
 	}
 
diff --git a/programs/open/main_test.go b/programs/open/main_test.go
index 57b501f..8f01766 100644
--- a/programs/open/main_test.go
+++ b/programs/open/main_test.go
@@ -105,6 +105,34 @@ func TestFindCommand_FileMissing(t *testing.T) {
 	}
 }
 
+func TestFindCommand_MimeSpecificFirst(t *testing.T) {
+	// More specific patterns should be tried first irrespective of their configured order.
+	filePath := path.Join(t.TempDir(), "test.svg")
+	_, err := os.Create(filePath)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	cfg := Config{
+		MimeTypes: map[string][]string{
+			"image/*":       {"general-image"},
+			"image/svg+xml": {"specific-image"},
+		},
+		UriSchemes: map[string][]string{},
+	}
+	// Running several times because if the priorization of specific patterns isn't
+	// implemented then it could succeed depending on the random map iteration order.
+	for i := 0; i < 10; i++ {
+		cmd, err := cfg.findCommand(filePath)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if diff := cmp.Diff(cmd, cfg.MimeTypes["image/svg+xml"]); diff != "" {
+			t.Fatal("unexpected command", diff)
+		}
+	}
+}
+
 func TestFindCommand_UriCheckedFirst(t *testing.T) {
 	cases := []struct {
 		uriHandlerExists bool